Keywords

2.1 Myanmar

2.1.1 Rice Cultivation in Myanmar

In Myanmar, rice has been a staple crop for many centuries. Today, it is one of the most important crops in the country. Rice is cultivated widely across the country, and the total rice cultivation area is 8 million hectares (ha). The Myanmar agricultural sector and, in particular, rice cultivation have been characterized by several changes over the past centuries. British colonizers established agricultural policies to boost rice production in the 1850s, moving to create a monoculture characterized by poor technological innovation. In the 1950s, Myanmar became one of the biggest global rice producers, which was unfortunately followed by a rice export collapse in the 1960s. As a result, Myanmar’s rice cultivation stagnated for many decades (Perry 2008). Nonetheless, agricultural production in Myanmar has become more market oriented since 1988 (Soe 2004). In 2010, a political restructuring took place that resulted in the establishment of the Myanmar Rice Industry Association, which aims to reorganize and modernize the domestic rice sector. In 2015, the Myanmar Rice Sector Development Strategy was launched, which was jointly conceptualized by the Ministry of Agriculture and Irrigation of Myanmar, IRRI, the FAO Regional Office Asia–Pacific, and the World Bank to boost agricultural productivity to transform rural areas that are highly dependent on rice farming (Kraas et al. 2017).

The aforementioned agricultural reforms enabled an increase in Myanmar’s rice production. Between 1995 and 2010, the total rice production increased from 18 Megatons (Mt) to over 32 Mt. However, the total rice production decreased to 25 Mt in 2017 (GRiSP 2013; Kraas et al. 2017; FAOSTAT 2023). During the same period, the average rice yields rose from below 3 t ha−1 in the 1990s to around 3.7 t ha−1 in the 2010s. In 2020, Myanmar ranked the world’s seventh-largest rice-producing country, following Vietnam and Thailand (GRiSP 2013; FAOSTAT 2023). This is also reflected in the 30% contribution rice cultivation makes to the country’s gross agricultural output since it also accounts for about 95% of Myanmar’s total cereal output and is Myanmar’s second most exported agricultural commodity after pulses. Still, a significant number of rural households are not able to have a sufficient intake of nutritious food with high rates of malnutrition due to limited purchasing power (Raitzer et al. 2015). About 30% of the rural households in Myanmar fall below the national poverty line (Michigan State University (MSU), Myanmar Development Resource Institute’s Center for Economic and Social Development (MRDI/CESD 2013). It can, therefore, be concluded that national self-sufficiency has not translated into food security for the poor.

Rice farming in Myanmar is characterized by subsistence-oriented agriculture in the lowlands, predominantly in the Ayeyarwady Delta, which contributes to approximately 31% of Myanmar’s total rice production, followed by Bago and Sagaing regions, which account for 17% and 11%, respectively (USDA—Foreign Agricultural Service 2020). Most rice cultivation (approximately 60%) takes place under rainfed conditions. An additional 20% of agricultural land is artificially irrigated. The major irrigated zones lie within the Ayeyarwady Delta, near the Bago Yoma dams (GRiSP 2013; Kraas et al. 2017).

Most farmers have access to less than 2 ha of land, with only one-third of the farming population having access to up to 4 ha of land (Kraas et al. 2017). Farmers generally use modern varieties introduced through various development programs (Connor et al. 2021a). However, the application of inputs to support cultivation is low due to limited access to the necessary inputs. As a result, farmers are not achieving the yield potential, and big yield gaps exist, as shown in the Bago Region (Stuart et al. 2016). Furthermore, Myanmar has considerably lower rice yields than other Southeast Asian countries (GRiSP 2013; FAOSTAT 2023). Some authors (e.g., Yuyu and Hye-Jung 2015) describe Myanmar’s rice production as being traditional, although mechanization has occurred recently. Farmers have, in general, limited access to formal sources of credit, access to irrigation systems, and postharvest facilities (such as mills and storage), and roads linking farms to markets are lacking and, consequently, rice production is negatively impacted (Connor and San 2021).

Even though development programs have aimed to introduce new and modern agricultural practices and technologies (Wehmeyer et al. 2022), Myanmar is still lagging behind its neighboring countries, especially in applying farm mechanization (Yuyu and Hye-Jung 2015). Rice is not a highly profitable crop for farmers. Rice production can be described as highly labor intensive with low labor efficiency due to a low degree of mechanization and low agricultural productivity. Yuyu and Hye-Jung (2015) outline that farmers need to use farm mechanization tools more efficiently to improve and modernize the agricultural sector, particularly rice cultivation. Training on the utilization of such mechanization tools and machinery is necessary to advance agricultural productivity and crop** intensity. While efforts have been made on the national policy level, these efforts have not been successful on a large scale due to the lack of skills, education, and training of the farmers as well as insufficient extension activities. Furthermore, the governmental mechanization scheme involving the distribution of farm machinery to farmers has not shown the expected effects (Yuyu and Hye-Jung 2015).

2.1.2 Constraints and Opportunities for Rural Development in Myanmar

As briefly described above, Myanmar lacks sufficient, high-quality infrastructure in rural areas. Therefore, producers and traders are forced to substitute the lack of public infrastructure by paying private companies, e.g., for fuel-based generators, in place of national electricity supplies. These are high-cost expenses that lower profits, hinder exports, and reduce incentives for other investments (World Bank 2014; OECD 2015; Snoxell and Lyne 2019). The lack and the development of an adequate financial system exacerbate this problem even further, leaving many smallholder farmers without access to formal credits or other financial opportunities to reinvest in their farming enterprises (OECD 2015; Snoxell and Lyne 2019). Farmers will often obtain agricultural credit through loans from family members, friends, or expensive moneylenders even though the government has been adapting their credit system and is providing more services to farmers (Snoxell and Lyne 2019). This results in a negative feedback loop due to farmers’ problems of low liquidity and lack of credit. It is hence difficult for farmers to accumulate savings and reinvest in their farms (Snoxell and Lyne 2019). Therefore, household income remains low.

Regarding rice production, access to agricultural inputs is a major constraint. For example, a lot of farmers use their own seeds instead of certified seeds because many farmers have either no financial means to buy certified seeds, the seed system is not sufficiently developed to provide enough certified seeds, or they are not easily accessible (World Bank 2014; OECD 2015). Additionally, seeds are often of poor quality due to weak extension support to seed multiplication farms and poor storage conditions of seeds (OECD 2015). From 2015 to 2021, the government focused on quality seed production (MoALI 2018). International Development Partners such as LIFT, United States Agency for International Development (USAID), and Japan International Cooperation Agency (JICA) invested in the quality seed production industry development. The International Seed Sector Development Myanmar program (https://issdmyanmar.org/about/) collaborated with Welthungerhilfe (WHH) in the Central Dry Zone to improve seed sector coordination, seed business development, and increase the availability of improved seeds for farmers. Farmers’ awareness of using quality seeds has been improved. However, there are still limited numbers of seed-producing farmers, and the accessibility of quality seed is still challenging for farmers both in the delta area and in the Central Dry Zone.

Along the rice value chain, a plethora of further constraints can be described, e.g., insufficient mechanization in land preparation and crop establishment processes, limited input use such as fertilizer and pesticides, and constraints in postharvest processing. There is a lack of dryers, storage facilities, modern milling equipment, and efficient transportation to markets after harvest contributing to high postharvest losses and poor quality rice, reducing its market value (GRiSP 2013).

Myanmar has great potential to produce green products, given its low use of fertilizers and pesticides in crops, livestock, and fisheries. Eighty-five percent of total chemical fertilizers in the country are imported from China and Thailand (Lwin et al. 2014), and the data from the Myanmar Statistical Information Service stated that Myanmar imported US$132 million in nitrogen-based fertilizers in 2018. Maize and rice farmers use more inorganic fertilizers than pulses farmers (IFPRI 2021), while vegetable farmers use both inorganic fertilizers and pesticides. The substantial increase in international inorganic fertilizer prices and ship** in 2021 resulted in higher border prices for fertilizers in Myanmar (IFPRI 2021). This further resulted in farmers returning to their conventional farming system with fewer inorganic fertilizers.

As described by Yuyu and Hye-Jung (2015), the agricultural extension system in Myanmar is weak, with little interaction between extension staff, researchers, and farmers. In general, agricultural extension programs are underfinanced, and extension workers do not possess adequate knowledge to share with farmers leaving many farmers behind in terms of knowledge acquisition (World Bank 2014).

In addition, the security of land tenure and production rights, especially freedom in crop choice, hinder agricultural development. In Myanmar, the state retains ownership of all land and farmers are granted land use rights (World Bank 2014; OECD 2015). For example, unresolved land tenure issues and mandatory crop** regulations increase farmers’ risks of investing in land improvements and farm commercialization, as well as perpetuate the vulnerability of smallholder and landless farmers resulting in many smallholder farmers avoiding changes and choosing to cultivate their land only to the minimum requirements, which impedes agricultural development (Wehmeyer et al. 2022). Therefore, policy changes are required that recognize the importance of secure rights for attracting investment in land development (World Bank 2014).

Like most Southeast Asian countries, Myanmar is also disproportionally affected by climate change due to its long and exposed coastline and the delta region. Farmers’ vulnerability to drought, flooding, salinity intrusion, and extreme weather events has significantly increased over the last decade and is expected to negatively impact agricultural production further. Studies have shown that farmers who have an adequate amount of knowledge of climate change and its consequences are more likely to accept new and sustainable technologies and practices (Connor et al. 2021a). Therefore, improving farmers’ knowledge about climate change and climate-smart agricultural practices is necessary in order to help them become more resilient and adapt to changes in climatic conditions (Myanmar Ministry of Agriculture and Irrigation 2015).

Despite the aforementioned difficulties, Myanmar remains a country with a large potential to develop economically, socially, and environmentally on the basis of the SDGs (Wehmeyer et al. 2022). Myanmar’s rural development initiatives are still in their early stages and, therefore, provide good opportunities to design and establish more robust strategies to achieve increased productivity, greater socioeconomic equality, and stability in social and economic development. Furthermore, there are a lot of learnings which can inform rural development strategies; for example, one aim should be to avoid mistakes that have been made in the past, such as agricultural input overconsumption and soil degradation due to monoculture agriculture which has been seen in Thailand, China, and Vietnam (OECD 2016; Holzhacker and Agussalim 2017). The potential for successful rural development is high in Myanmar. Myanmar benefits from an advantageous geostrategic position bordering India in the west and China in the east as well as being part of ASEAN (Wehmeyer et al. 2022). This opens several trading opportunities to serve the growing Asian markets as well as also becoming a more important global exporter. This requires, however, the development of policies that exclusively focus on domestic agricultural production systems, exports, and pricing regulations, but also on reducing trade barriers (Myanmar Ministry of Agriculture and Irrigation 2015; OECD 2016; Aung 2019). Furthermore, Myanmar also has the necessary natural resources, such as vast amounts of cultivable land, water resources, and generally favorable climatic conditions. Finding avenues to provide farmers with the necessary infrastructure, such as roads, irrigation facilities, adequately trained extension services, and machinery, will considerably improve agricultural production. Different ways can be explored, such as a greater promotion and involvement of the private sector and investments in critical public services (e.g., road and electricity infrastructure, education and research, health services, and social protection) (OECD 2016; Wehmeyer 2021).

2.1.3 CORIGAP Activities in Myanmar

The CORIGAP activities in Myanmar started in 2013 with the objective of introducing sustainable best management practices in rice production to reduce rice yield gaps due to unfavorable environments and high postharvest losses (Wehmeyer 2021). These best management practices include primarily the introduction of balanced nutrient management and postharvest technologies that help farmers increase their rice yields and improve agricultural efficiency (IRRI 2018). Activities in Myanmar focused on promoting learning alliances, develo** business models, establishing joint in-country training activities, and supporting gender research (Singleton and Labios 2019; Connor and San 2021). Therefore, improved rice and pulse varieties were introduced. Adapted inputs for better nutrient use management, ecological rodent management, and specific machinery, such as drum seeder, mechanical transplanter, combine harvester, lightweight thresher, flatbed dryer, and storage bags for rice seed were introduced to farmers in the Ayeyarwady Delta and Bago Region (Singleton and Labios 2019; Connor and San 2021; Wehmeyer et al. 2022).

In order to facilitate knowledge exchange, farmers and other stakeholders associated with rice farming, such as millers, traders, government officials, and NGOs, were invited to participate in learning alliances by the CORIGAP team. Learning alliances were held at the village level to provide information and exchange knowledge between the different stakeholders (Singleton and Labios 2019). Adaptive research combined with the learning alliance approach realized positive outcomes (Flor et al. 2017). In Maubin Township, in the Ayeyarwady Region, a learning alliance introduced farmers to lightweight threshers and new varieties (Quilloy 2014; Wehmeyer et al. 2022). Further activities concentrated on using good-quality seeds, reducing postharvest losses, and develo** business models for implementing postharvest technologies to improve farmers’ livelihoods. The IRRI postharvest team, together with the national partners, implemented postharvest demonstration trials where principles of grain quality, drying, and hermetic storage were discussed. Furthermore, participants were introduced to postharvest techniques to produce good-quality grains through threshing, drying, and storing (Quilloy 2014; Wehmeyer et al. 2022).

The introduction of high-yielding varieties was another component of the CORIGAP activities in Myanmar. These varieties have been developed using a “bottom-up” approach to varietal selection that was introduced by IRRI under a different project (Rahman et al. 2015). Participatory varietal selection field trials were established together with farmers that also focused on making best management practices more accessible to farmers, including sustainable pre-and postharvest activities, such as direct seeding, proper fertilizer application, and weed and herbicide management (Singleton and Labios 2019). Large field demonstrations to introduce best management practices were conducted in Hlegu Township (Yangon Region; 7 ha), Letpadan Township (Bago Region; 40 ha) from 2015 to 2017, and Pyinmana Township (Nay Pyi Taw Region; 20.3 ha) in 2020–2021. Furthermore, a combination of best management practices for rice production was conducted as a large field trial demonstration in Letpadan Township with six farmers in the 2016 wet season. The technologies were taken up by neighboring farmers quickly (Box 2.1).

Box 2.1: Success Story of the Large-Scale BMP Demonstration Trial in Myanmar

Increasing rice yield by using improved technologies was established in Myanmar in 1986 as a national program financed by the government. The CORIGAP project started as the Irrigated Rice Research Consortium (IRRC) project in Myanmar in 2005, which was aligned with national policy. The IRRC project introduced new technologies to rice farmers in Myanmar, such as Site Specific Nutrient Management (SSNM), Alternate Wetting and Drying (AWD), the use of drum seeders, and the use of hermetic storage bags and flatbed dryers. Adaptive research, involving close linkages and feedback from farmer groups, and learning alliances among farmers, researchers, and extension staff from both the public and private sectors have played a powerful role in this process (Flor et al. 2017). One of the large-scale demonstration trials in the Bago Region supported the evidence of technology adoption in the project.

Background information on the process

A large field trial demonstration in Letpadan Township was conducted with six farmers in the 2016 wet season. A package of best management practices (BMP) was developed based on the challenges identified by farmers. The field experiments were conducted at Kyoet Pin Sa Khan Village (17° 47.45ʹ N, 95° 48.18ʹ E), Letpadan Township, Tharrarwaddy District, Bago Region. The major crop** patterns are rice-rice and rice-pulse, and farmers practice wet direct seeding in flooded areas. At the end of the crop** season, a farmers’ field day was organized with collaborating farmers to share their findings and experiences with other farmers and local authorities. An Exchange Farm Visit program was organized for the farmers from another region (Nay Pyi Taw) to learn about the experiences of Letpadan farmers.

Technology adoption

Since the start of the trial, the neighboring farmers of the BMP farmers copied the technologies that BMP farmers practiced. All information was recorded through a farmer diary data collection process. Furthermore, yields from the plots of BMP farmers, modified farmer practices (Modified FP), and traditional farmer practices (FP) were harvested and compared. In the 2016 dry season, BMP yield (5.1 t ha−1) was 12% higher than the modified FP yield (4.5 t ha−1) and 26% higher than FP yield (3.8 t ha−1) (Fig. 2.1). However, the cost and benefit ratio of BMP and Modified FP was not significantly different.

Fig. 2.1
2 bar graphs with error bars. First. It plots yield ranging from 0 to 7 versus B M P yield, modified F P, and F P yield. The maximum yield is approximately 6 for the B M P yield. Second. It plots yield versus B M P, M F P, and F P. The maximum yield is approximately 3.5 for M F P.

Comparison of yields and cost–benefit ratio between Best Management Practice (BMP), modified farmer practice (modified FP), and farmer practice (FP)

Full size image

BMP practices, and cost and benefit information, were shared with other farmers by the BMP farmers during the field day. Within a year, the area cultivated under BMP increased to 34.8 ha through the strong collaboration of BMP farmers and the Department of Agricultural Extension at the township level. In the 2017 dry season, BMP farmers’ yield was 3.4 t ha−1 higher than FP farmers’ yield, and the benefit was increased to 284 US$ ha−1. Usually, the adoption and diffusion pathway of a new technology takes five years or above. However, BMPs were adopted by farmers from 13 villages within two years of the project. The two key success factors of this project were:

  1. i.

    The introduced technologies were proven research outcome technologies from the regional level, which are simple, affordable, and adaptable and

  2. ii.

    The strong collaboration of local champions, both from the farmer group and from the local department extension staff, facilitated fast adoption.

Source DoA CORIGAP annual presentation, 2021

2.1.4 Adoption of Best Management Practices and Changes in Rice Production

The CORIGAP project reached more than 25,000 households in Myanmar. The learning alliances facilitated the active participation from both public and private sectors and the subsequent formation of a network between farmers and providers (Wehmeyer et al. 2022). This resulted in the development of a market model for mechanical dryers, in particular, the solar bubble dryer, and supported a local manufacturer in making lightweight threshers (Singleton and Labios 2019; Wehmeyer et al. 2022). These aspects will be further described in Chap. 6.

As part of the monitoring and evaluation activities (described in Sect. 7.2), the CORIGAP project collected data on various aspects that indicate change for farmers. The aim was to capture social, economic, and environmental changes. In collaboration with the national partners, the CORIGAP team collected data on 129 farmers from the Bago Region in the Ayeyarwady Delta. These farmers were project farmers and had attended CORIGAP training events. There were two groups of farmers: one group followed a rice-rice crop** pattern, and the second group followed a rice-pulse crop** pattern. The objectives also included investigating the adoption of the practices and technologies that were introduced in the area. We were particularly interested in the reasons for adoption but even more so in the non-adoption or even disadoption, where farmers decided not to continue with a practice or technology. We found that farmers adopt new practices and technologies when they gain higher yields, have reduced costs, and can save labor (Connor et al. 2021a). Reasons for non-adoption and disadoption were unsuitable practices and high costs associated with new practices and technologies. Most of the farmers in the two regions adopted the high-yielding varieties; some farmers even changed varieties more than once. In addition, combine harvesters, nutrient management practices, and post-emergence herbicides were adopted widely (a detailed description can be found in Connor et al. [2021a]).

Comparing the two groups of farmers (rice-rice and rice-pulse) showed that rice-pulse farmers had higher yields during the monsoon season (the season when farmers produce rice) than rice-rice farmers. Apart from that, no other differences were found between the two groups. Input costs, gross revenue, and net profit were very similar between the two groups (Wehmeyer et al. 2022). We conducted further analyses based on the farmers’ net change in income, and two groups were created; one containing farmers that had a positive change in net income and the second group was comprised of farmers that did not have a change in net income. There were no farmers that had negative changes in net income. In other words, none of the farmers in the sample experienced a decrease in their income. The analysis showed that farmers with a positive change in income had a higher yield than farmers who did not have a change in income. These farmers also adopted more of the introduced technologies and practices. On average, these farmers were able to increase their income by 113 US$ ha−1, mostly due to an increase in yield and reduced production costs (Connor et al. 2021a).

Farmers were not only asked what type of technologies and practices they had adopted but also why they did not adopt or decided not to continue using the practices and technologies. They were also asked for the reasons for such a decision to provide us with a better understanding of technology adoption or non-/disadoption. Multiple reasons were mentioned for adoption, e.g., higher prices in the market for new varieties, fewer yield losses when using drought-resistant varieties, or the reduction of costs when using machinery such as a combine harvester or lightweight thresher. Similarly, farmers described difficulties when not adopting or disadopting a practice. In some cases, farmers were not able to source new varieties or inputs (e.g., herbicides). In other instances, farmers expressed that, e.g., nutrient management was too expensive or there was a labor shortage, so new practices could not be implemented. Some farmers experienced difficulties using certain technologies and also felt that others may not be suitable for their specific crop** pattern. This highlights the importance of an adaptive participatory approach when introducing new technologies and practices. It is essential to let farmers experience the new practices and technologies and to keep discussing their experiences to advise them appropriately and to refine practices and technologies that are identified as less suitable (Connor et al. 2021a).

2.1.5 The Changes Farming Families Perceived Since Adopting New Technologies and Practices

Knowing that farmers adopt and benefit financially from new technologies and practices is one way to assess possible changes in farming communities. Traditionally, this was the main avenue also to determine impact. However, it is not always easy, nor advisable, to quantify changes or impact, especially in complex environments where several interventions take place at the same time, as described for Myanmar. Therefore, we conducted qualitative interviews with rice farmers to better understand their perception of change due to technology adoption (Connor et al. 2021a). We conducted 32 interviews with the farmers that have shown a net increase in income and asked them about the changes they have perceived. The interviews started very freely but were guided by a semi-structured interview guide. Farmers foremost explained the changes they had seen in yields through the adoption of the new varieties. Some farmers also explained how they changed their crop** system from rice-rice to rice-pulse due to an increase in prices for pulses. Furthermore, farmers explained how cost-saving technologies such as using a drum seeder allowed them to use the extra money for other inputs that they previously could not afford to boost their rice production. Especially, cost- and labor-saving technologies were adopted widely, which changed farmers’ everyday activities considerably. Hence, the workload farmers faced was reduced, and they could account for the labor shortages experienced in the region. Furthermore, farmers experienced significant changes in living conditions, they explained how they have more time and money to repair their houses, and they are able to purchase different types of food and pay for education services for their children. One aspect that was frequently mentioned was how farmers use their extra time and money to serve their community. Donations to the pagoda are part of most people’s personal duties in Myanmar (Connor et al. 2021a; Connor and San 2021). Village activities and social events are centered on these religious institutions, and the rural population comes together to build roads and/or canals. Such activities have increased over the past years, and a contributing factor was the adoption of labor-saving technologies.

As part of the aforementioned data collection, we also collected quantitative data on how the farmers spend their additional income. The findings are very much in line with the qualitative interview results in that they show that farmers first chose religious activities followed by food, health care, and education. These findings show that the introduction and adoption of new technologies and practices can trigger quite far-reaching changes at the individual and community levels. What became evident during our research was that we mostly spoke to male farmers. They also dominated our quantitative data collection sample. Roles in Myanmar are gender related, where men and women have particular roles in society, community, and household. With regard to rice farming, women participate in seed-saving, weeding, and transplanting, while men practice plowing and operating other equipment (Faxon 2017). We were also interested in knowing how other family members perceive the introduction of new technologies and practices and how the adoption thereof influences families as a whole. Therefore, we interviewed the wives of the farmers that had adopted new technologies and practices. The interviews were unstructured, and the women were encouraged to tell us about their lives and the changes they had experienced over the past few years (Connor and San 2021). During the interviews, women would explain how the new technologies and practices were brought into the region. They were excited to tell us all about the good things but less so about the not-so-good ones. According to some women, the only bad thing was that the training activities were held at times when they couldn’t come to participate because they were busy with the children or housework. This seems to be a common factor hindering women from participating in training events. When women have small children, it often is difficult to find someone to look after them during training sessions. Furthermore, when training sessions include the introduction of machinery, it can be dangerous for young children to be brought to the training. Future projects need to take those constraints into account and find avenues to include women’s participation.

Depending on families’ economic status, the changes families experienced differed. All women talked about positive changes and how their families reinvest in their farming business. Some used the extra income to lease more land. Another family could buy machinery and become a service provider for agricultural machinery, such as tractors and combine harvesters. This family was economically more secure than others in the sample. A young woman with small children explained how she is happy that she can now serve three meals a day and that her children do not need to be hungry. Interestingly, for some women, the change in income meant that they were able to pursue their own career aspirations. One woman, who worked as an input provider, dreamt of becoming an extension officer. Another woman explained how the extra income enabled her to open her own little shop where she sells household goods. Most of the interviews were conducted in participants’ houses, and we were shown around to see all the new things that families acquired over the past years. They were able to improve their housing conditions, repair roofs, getting electricity installed, and one family even purchased a small solar panel to generate their own electricity. Similarly to male interviewees, women also explained how the extra income supported their children’s education, both school and university education. One woman talked about how she could afford health care for her elderly parents, and another one how she established a big kitchen garden that produces enough vegetables for her to sell at the local market. This only provides a small insight into the multitude of changes families can experience due to an increase in income from rice farming. Changes obviously differ depending on the economic status of the families (Connor and San 2021). Smallholder farmers are not a homogeneous group, and the introduction of new technologies and practices will affect each farmer and their respective family differently.

2.2 Thailand

2.2.1 Rice Cultivation in Thailand

Thailand is the 6th top rice producer as of 2022 (FAOSTAT 2023) and is one of the top three global rice exporters, together with India and Vietnam, situated in the world’s rice bowls in Southeast Asia (ASEAN Vietnam 2022). Rice is Thailand’s primary agricultural export product (USDA 2022), with exports reaching US$ 1.7 billion in the first half of 2022 (Rice Today 2022). A study by Kealhofer (2002) found that rice cultivation in north and central Thailand started in the “middle Holocene” period about 7,000–5,000 years ago. Since then, rice has been a staple food in Thailand and fundamental to the country’s culture (Roaf 2022); it is used in religious ceremonies such as weddings and offering to Thai Buddhist monks (Roaf Thai Ginger 2023).

Thailand is in the middle of mainland Southeast Asia with a total size of 513,120 km2 and has a fertile floodplain. The country has 32.9% of arable land (The World Bank 2020). Over half of the arable land in Thailand is cultivated for rice, which is grown by 4 million out of 8 million farm households (Bangkok Post 2020). The area cultivated with rice increased by 2.65%, and production increased by 3.63% from 2016 to 2021 (FAOSTAT 2023). The major rice-growing regions are located in the central, north, and northeast, with a respective share of 24, 20, and 50% of the country’s total rice area (GRISP 2013; USDA 2015).

Thailand is characterized by a favorable climate and fertile soil, which makes it suitable for rice production (The World Bank 2022). The main four ecosystems in Thailand are (a) rainfed lowland (72% of the total paddy field and mainly located in the northeastern region), (b) irrigated lowland (20% of the total, located in the Central plain, (c) deep water (5%), and (d) upland rainfed land (3%) (Pongsrihadulchai 2018).

Thailand’s rice policy has undergone several changes over the last decades. In 1955, a rice premium export tax was introduced with the following objectives: to secure government revenue, to stabilize the domestic rice price resulting from fluctuating world prices and domestic supply, and to control the exporters’ excess profits (Tsujii 1977). Moreover, the rice premium export tax was abolished in 1986 since it consequently resulted in heavy taxation on farmers, higher domestic demand, lower exports, and lower foreign currency receipts.

After the democratic movement in 1973, Thailand shifted from an urban-biased development approach by which urban development is favored to a producer-biased approach (Poapongsakorn 2019). The government introduced paddy pledging schemes for farmers in 1980–1982 and in 2000–2001, providing subsidized non-recourse loans to farmers who did not want to sell paddy in the early harvesting season. In the 1980s and 1990s, most agricultural policies provided incentives to encourage farmers to grow crops other than those with diminishing prices, such as rice and cassava. Following the economic crisis and the constitutional reform in 1997, agricultural policy shifted toward providing subsidies to farmers. The succeeding policies from 2000 to 2018 started on price support and market intervention for almost three years and reverted to a minimum income subsidy for farmers with minimal market intervention.

The rice policy review by Forssell (2008) emphasized that the rice policy by the end of the twentieth century would become neutral for producers and consumers. The beginning of the twenty-first century favored the producers when the mortgage program was introduced. However, the reintroduction of high pledging prices on the first and second crops in 2008 caused huge harm to the domestic rice industry. The main ultimate goal of the scheme was to increase rice prices to protect farmers from middlemen. The government gave farmers higher crop prices than what they would have received from middlemen. The immediate results of the high pledging process policy included a slowdown in exports since supply decreased, high domestic prices, and large government expenditure.

To avoid causing more damage to the Thai rice industry, the government eliminated the paddy pledging scheme from 2014 to 2018. Recently, Thailand’s rice policy and management committee agreed to allow another year to resolve the controversial rice-pledging scheme since the pledging scheme resulted in unsold rice of 218,000 tons. Most of this rice deteriorated considerably in quality and was often sold as inedible rice to be converted into bio-fuel (Thai PBS World 2022). In a new attempt, Thailand’s Rice Policy Management Committee has approved a budget of about 150 billion baht to guarantee the income of more than 4.6 million farming households for their 2022–2023 rice crops (Thai PBS World 2022; Bangkok Post 2022). The state will set the minimum rice market price to be updated within seven days and will pay the price difference to farmers who are unable to sell their crops at the set prices. Moreover, to encourage farmers not to sell their produce at a time when the prices drop, each farming household will get a subsidy of 1,000 baht per 0.16 ha but will not exceed 3.2 ha or 20,000 baht in total (Thai PBS World 2022).

2.2.2 Constraints and Opportunities in Rice Production

Thailand has a favorable climate and vast land for rice cultivation. Moreover, the combination of the use of technology, advanced knowledge of rice strains and fertilizers, helpful government policies, and massive investment in infrastructure improvements, agricultural research, and road networks in the 1970s all led to a per unit of land increase of 50% in rice production (Poapongsakorn 2011; Wailes 2012; Laiprakobsup 2019). Thus, the synthesis of all these factors paved the way for Thailand to be one of the largest rice producers and top exporters of rice globally.

Thailand consistently ranked as the first rice exporter globally in the past 30 years. The country lost its position to India and Vietnam in 2012 (Pongsrihadulchai 2018; Kishimoto 2021). The move down in the ranking resulted from several reasons:

  1. i.

    Decreasing rice production caused by droughts and unpredictable wet weather.

  2. ii.

    Higher export prices and freight charges (Kishimoto 2021; Promchertchoo 2022).

  3. iii.

    The paddy pledging scheme in 2011 contributed to the weakening of the export competitiveness of Thai rice relative to its competitors in terms of export price and quality.

    The export price of Thai rice was higher than the export prices of its competing countries, such as Vietnam and India, with the belief that Thailand has the market power to raise the export price in the global rice market by stockpiling and decreasing its exports (Mahathanaseth and Pensupar 2014). However, the study on the rice-pledging scheme by Mahathanaseth and Pensupar (2014) indicated that Thailand does not have the market power to influence export prices in its four major export markets, including China, Indonesia, the USA, and South Africa. Moreover, Thailand faces extreme competition from Vietnam and India, whose rice appears to be a very good substitute for Thai Rice (Mahathanaseth and Pensupar 2014; Promchertchoo 2022).

  4. iv.

    Thai farmers rely heavily on chemical pesticides and fertilizers to improve rice production.

    Farmers, in general, are risk-averse, resulting in excessive use of chemical inputs which can negatively affect the environment and the net income of rice farmers. Consequently, increasing the production and selling costs of rice and raising the export price of Thai rice.

    The number of pesticide products applied increased from 2 to 7 kg ha−1 from 1997 to 2009 and further increased to 8 kg ha−1 in 2012 (Praneetvatakul et al. 2013). Pesticide poisoning remains a common work-related illness in Thailand (Ministry of Public Health 2020), which means certain measures are needed to prevent more cases of poisoning.

    Approximately 47% of the fertilizer consumed in agriculture was used in rice production (Wannarut et al. 2014). Fertilizer consumption increased from 0.2 to 2.6 million Mt from 1970 to 2010 (Wannarut et al. 2014).

  5. v.

    High labor costs lead to higher production costs, which is reflected in Thai rice production and price.

All the above-mentioned constraints, if resolved, can greatly help Thailand gain back its position as the world’s top exporter. The government is keen to expedite its way back to the top. Among the avenues are the following:

  1. i.

    Lowering export surcharges to improve the export price competitiveness of Thai rice.

  2. ii.

    Increasing rice production with emphasis on environmentally safe management practices for sustainable rice production, which includes efficient use of inputs such as (a) water, (b) pesticides and fertilizers, and switching to organic options, and (c) proper management of straw and other rice crop residues that is using rice straw for other purposes like mushroom production rather than burning it.

  3. iii.

    Cost Reduction Operating Principles (CROP) was promoted by the Thai Rice Department, which is complementary to (ii). Efficient use of available natural and chemical inputs ultimately reduces the production costs (while simultaneously reducing the negative impact of rice production on the environment), consequently increasing farmers’ income and competitiveness of Thai rice.

  4. iv.

    Investment in (a) high-quality rice breeds for exports that can compete with the existing rice varieties in the global market and (b) infrastructure for the ease of transporting rice within the country.

2.2.3 CORIGAP Activities in Thailand

CORIGAP introduced Best Management Practices (BMPs) in the Central Plains of Thailand in collaboration with the Rice Department Ministry of Agriculture and Cooperatives. The five significant activities implemented in 2013 were focused group discussions, a baseline household survey, an environmental indicator workshop and discussions, and capacity-building activities. The focused group discussions were conducted in Ban Nong Jik Ree and Ban Sapan Song in May 2013 to assess the needs and behavior of farmers. Farmers from Nong Jik Ree grow rice for seed production, while those from Sapan Song grow for grain production.

The baseline household survey conducted in November 2013 (more information in Sect. 7.2) intended to obtain necessary information on farmers’ practices before introducing any intervention. Eighty-four farmers were interviewed from four villages of Nakhon Sawan: Nongjikree, Sapansong, Packluk, and Sakaeggo.

The Rice Department arranged workshops to facilitate identifying environmental indicators in measuring the ecological footprint from farming practices and technologies adopted in rice production in November 2013, attended by about 50 participants. Follow-up meetings were conducted until 2015 to discuss protocols for ecological indicator monitoring. Three staff from the Rice Department were trained at IRRI headquarters: one attended the rice post-production training course in October 2013, and two attended the ecologically-based pest management training course in November 2013.

The BMPs on cost reduction operating principles (CROP), AWD, drum seeding, fertilizer, pest, and postharvest management (hermetic storage) were established at CORIGAP sites in 2014. The activities were promoted through farmer participatory demonstration trials and field days. The CROP approach fostered fertilizer rates based on soil analysis, the use of certified seeds, reduced seed rates, and reduced chemical application. Protocols for monitoring water and soil quality were developed and executed in the wet season of 2014. Trials on using the Superbag were conducted in Ban Nong Jikree to compare the rice seed quality between Grainpro-Superbags and traditional storage systems. A Participatory Impact Pathway Analysis (PIPA) workshop was held in 2014 to discuss and better understand how various actors gather and use data on ecological indicators.

The plant growth-promoting rhizobacteria (PGPR II) and bio-fertilizer (LDD#12) are bio-fertilizers promoted by the Department of Agriculture and Land Development Department mainly to reduce the application of chemical fertilizers. Both bio-fertilizers can fix atmospheric nitrogen (N) to lower the amount of chemical fertilizer applied to the soil (Pame 2016; Pame et al. 2023). Moreover, PGPR II is mixed with seeds before broadcasting, while the bio-fertilizer LDD#12 is mixed with the soil during land preparation.

Laser leveling was also promoted in collaboration with Thai Rice NAMA, the Rice Department, and Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) to replace high-methane emitting approaches.

A joint workshop on Adaptive Research for Target Groups and Best Practices from the CORIGAP project was held from November 28 to 30, 2022, in Chainat Province, Thailand (IRRI 2022). It was a collaborative activity between experts from the Chainat Rice Research Center (CRRC) and the IRRI-CORIGAP project aimed to share the best practices and technologies of the project with broader groups under the Thai Rice Department to capture their perceptions on the effectiveness and relevance of the presented interventions, and ultimately help them replicate and integrate these into their division’s agenda even after the termination of CORIGAP (IRRI 2022).

2.2.4 Adoption of CORIGAP Technologies and Changes

Under the CORIGAP project, field trials were established to investigate different BMPs, such as CROP recommendation, Alternate Wetting and Drying (AWD), and the use of drum seeders. Stuart et al. (2018) compared the three best management practices (CROP recommendation, CROP+AWD, CROP+drum seeder (DS)) with farmers’ practice (FP) in eight field trial sites in the Chao Phraya River Basin in terms of input use (fertilizer, seeds, water) and income. CROP recommendations had lower fertilizer inputs of 64% and higher net income of 24% per season versus FP without yield penalty. The CROP+DS treatments had lower seed rates by 67% and higher income than FP. Forced AWD was followed when the study was conducted due to water shortage, yet high yields were still achieved with AWD practices. In summary, the study showed that an increase in income paired with reducing inputs that would otherwise cause adverse environmental impacts could help enhance the sustainability of rice production.

Replicated production scale trials of CROP in combination with land laser leveling (LLL), the use of mechanical drum seeders, and the application of the bio-fertilizers PPGR and LLD#12, which contains Azotobacter tropicalis, Burkholderia unamae, and Bacillus subtilis, were investigated by Pame et al. (2023). The study’s objective was to see how the different combinations can help improve the sustainability of rice cultivation in Central Thailand. The study found that CROP+PGPR had significantly higher net income (79%) and nitrogen-use efficiency (57%) compared with farmer practice. All CROP treatments had lower pesticide use (28%), seed rate (60%), inorganic fertilizer nitrogen (41%), and lower total production costs (19%) compared with FP. These results provide evidence-based findings that the practice of CROP, LLL, mechanical drum seeders, and bio-fertilizers can vastly enhance rice production’s economic and environmental sustainability in the Central Plains of Thailand.

A cross-sectional survey with 170 farmers, of which 108 were female, investigated the different changes farmers have perceived over the last years since CORIGAP interventions were introduced. Farmers were recruited from ten different villages, four from Nakhon Sawan and six from Chainat. Farmers had a choice of adopting multiple technologies and practices and, on average, adopted 2 (SD = 1.3) technologies and practices in the dry season and 2.5 (SD = 1.1) technologies and practices in the wet season. There were no statistically significant differences between male and female farmers in the average number of technologies and practices they adopted. Almost all farmers (n = 168) indicated that they were using a combine harvester, 71% (n = 121) adopted new varieties, 33.5% (57) of the farmers adopted improved fertilizer management, and another 20.6% (n = 35) adopted AWD. There were no differences between the number of male and female farmers adopting the different technologies and practices. Our analysis further found that farmers reported an increase in yield of 1.5 tons ha−1 (SD = 1.4) in the dry season and 1.9 tons ha−1 (SD = 1.7) in the wet season, which is associated with adopting best management practices. This, in turn, accounts for an approximately 26% increase in yield per season. Up to 25% of the farmers reported that input costs have decreased, while the rest reported that costs had stayed the same, indicating minimal general savings on production. Nonetheless, the yield increments directly translate to an added revenue of US$ 359 ha−1 (SD = 332) to US$ 458 ha−1 (SD = 397) in the dry and wet seasons, respectively, with an estimated increase in earnings from rice of 25 to 32% per season. Half of the farmers surveyed, 51% (n = 86), perceived that their income increased since adopting the best management practices. We disaggregated the data by gender and conducted the same type of analysis, and found that there were no statistically significant differences between male and female farmers. Farmers who perceived an increase in income were asked if they could remember how they used the additional income. Only half of the farmers could actually remember. Most farmers indicated that they put the additional income into savings or invested in their rice farming activities to buy either machinery or inputs.

We also asked farmers if they have perceived other changes in the same way as reported by Connor et al. (2021b, c) using different dimensions of change. These dimensions included financial capital, employment opportunities, physical capital, poverty reduction, land tenure, health, food security, social capital, human capital, and natural capital. Farmers perceived great changes in social, cultural, and natural capital. In other words, farmers reported that they now feel able to provide advice to their fellow farmers on how to improve their farming practices. They feel that they can devote more time and resources to community and cultural or religious activities. A lot of farmers also indicated that they see a lot more wildlife in their fields. In general, male farmers perceived more changes in these three areas than female farmers.

2.2.5 Conclusions

The adoption of best management practices under the CORIGAP project led to significant improvement in the economic and environmental sustainability of rice production in Thailand. Field trials have demonstrated that BMPs such as CROP recommendations, AWD, the use of drum seeders, land laser leveling, and bio-fertilizers can help increase yields, reduce input costs, lower pesticide use and inorganic fertilizer nitrogen, and enhance nitrogen-use efficiency.

Moreover, a cross-sectional survey of 170 farmers showed that the adoption of BMPs has led to an approximately 26% increase in yield per season, resulting in an estimated increase in earnings from rice of 25 to 32% per season. Farmers also reported an increase in their ability to provide advice to fellow farmers on improving farming practices, as well as an increase in their ability to devote time and resources to community and cultural or religious activities.

The benefits of BMP adoption go beyond just economic and environmental sustainability. By promoting the adoption of BMPs, not only can farmers increase their yields, lower their input costs, and reduce their environmental impact, but they can also enhance the social and cultural fabric of their communities and support the natural ecosystems that surround them. As farmers adopt BMPs and see improvements in their yields and income, they may be better able to invest in their families and communities. They may have more time and resources to participate in cultural and religious activities, strengthening social ties and building community cohesion. Additionally, the use of bio-fertilizers and reduced pesticide use can help support the natural ecosystems that surround rice farms, leading to benefits such as improved water quality and increased biodiversity.

BMP adoption is a multifaceted solution to improving rice production sustainability and highlights the importance of promoting BMP adoption both in Central Thailand and in other regions where rice farming is a critical part of the economy and the environment. The adoption of BMPs does not only enhance the sustainability of rice production but can also have positive impacts on social, cultural, and natural capital.

2.3 Indonesia

2.3.1 Rice Cultivation in Indonesia

The need for rice as the main food of the Indonesian population continues to increase from year to year. In 2045 when Indonesia will celebrate their 100th year of independence, the population is estimated to be around 325 million people, and domestic rice needs will reach 47.9 million tons (Sulaiman et al. 2018). The government set a production target of 92.3 million tons of dry-milled grain or an equivalent to 57.9 million tons of rice, and a surplus of 10.0 million tons of rice to be exported (Sulaiman et al. 2018). Meanwhile, the area of paddy fields as the backbone of national rice production to date is around 8.2 million ha, of which 4.75 million ha (58%) has irrigation infrastructure, including 2.2 million ha of technical irrigation (Wahyunto 2009).

The current rice cultivation area is too small to meet food sufficiency in the future if it is not offset by increased productivity, an increase in the area of technically irrigated rice fields or the creation of new rice fields. Agricultural land conversion poses a serious threat to achieving and maintaining food independence (Mulyani et al. 2016). In addition, there are various challenges in maintaining rice self-sufficiency, including increasing land degradation, limited water resources, limited availability of suitable land for area expansion (Mulyani et al. 2016), and increasing pest and disease populations (Hendarsih and Sembiring 2007). Climate change characterized by shifts in rainfall patterns, extreme climate events, and rising sea levels also threatens rice production (Sembiring et al. 2008).

The Integrated Crop Management (PTT) approach has been the mainstay of the Ministry of Agriculture in an effort to increase rice productivity and production in Indonesia. PTT’s approach is based on land, water, plant management and plant pest control, highlighting the synergy between technological components and soil, water, and environmental resources. The main objectives are increased productivity to break through leveling off of yields, increased efficiency of production factors for increased income, and improved soil fertility and environmental quality (Badan et al. 2014).

The supporting technology components of PTT are dynamic, following the development of science and technology and information technology. The leverage point in the reorientation and transformation of PTT as the basis of precision farming systems is the refocusing of technological components and the support of information technology in its dissemination systems.

Indonesia has a goal to be food independent and sovereign. The government, from era to era, continues to strive to increase rice production to provide national rice reserves. Through the Special Efforts Program (UPSUS), in the current government era, Indonesia managed to achieve rice self-sufficiency in 2016. Rice PTT based on soil and water resource conservation characterized by a precision agriculture system is believed to be able to answer the challenges of maintaining national food independence and sovereignty in a sustainable manner and making Indonesia a World Food Barn.

2.3.2 Challenges in Indonesia

2.3.2.1 Rice Situation and Challenges in Yogyakarta

Yogyakarta is one of Indonesia’s rice-producing areas, with an average harvested area of 110,000 ha for the last decade. The rice crop** index is about 2–2.5 in a year (5 rice harvests within two years), and production occurs predominately in irrigated agroecosystems. Yogyakarta’s rice production reached 319,200 tons of milled rice in 2021, with an average yield of 5.21 t ha−1. However, there are some significant challenges to maintaining this high level of rice production in this area. The rate of annual rice consumption is high (81.4 kg per capita and year), and combined with the high rate of population growth (5.53% per year, Yogyakarta population is 3.71 million), results in growing pressures to produce sufficient rice to fulfill the increased demand (BPS-Statistics 2022a). Other challenges are the land conversion from rice farming to other purposes resulting in limited growth in rice harvested area, combined with problems of smallholder farm size, limited water availability, pest and diseases, and labor shortage. Yogyakarta had not established new rice fields since 1996. In contrast, over twenty years, the rice fields were reduced by 7,968 ha or about 257.5 ha per year. This reduction relates to the conversion of land from rice farming to other purposes (Herdiansyah et al. 2020; Central Bureau of Statistics (BPS 2018).

Most Yogyakarta farmers own small land holdings with cultivated areas for rice on about 1,400 m2. Input costs in rice farming include seeds, fertilizers, pesticides, irrigation fees, hired labor, and cover for machinery rental costs (Connor et al. 2021b). With their small land size, farmers face challenges in applying fertilizer and using seeds at the recommended rate, combined with their knowledge regarding healthy and vigorous plants which bear a resemblance to dark green leaf color. This condition causes excessive application of nitrogen. According to Devkota et al. (2019), more than 80% of farmers planted certified seeds, but most used more seeds than required by 40–45 kg ha−1. With regard to fertilizer usage, more than 74% of farmers applied N, and more than 67% of farmers applied P and K. In Yogyakarta, the local recommended rate for N is about 250 kg ha−1, where most farmers applied N by 200 kg ha−1. Meanwhile, the topmost farmers exceeded the recommended rates without an overall increase in yield (Stuart et al. 2016). The rate of N, P, and K application was, on average, 200 kg, 22 kg, and 45 kg ha−1, respectively (Devkota et al. 2019).

Water shortage which occurs in particular areas during the second crop season also becomes a constraint. According to Devkota et al. (2019), the total number of irrigations per crop** season in Yogyakarta is quite low, but it increased to 45% during the dry season. However, the water productivity is high, which means that fields in Yogyakarta exploited 2100 l of irrigation water and rainfall to produce 1 kg of grain.

The main pests and diseases in Yogyakarta during the last decade were rodents, stem borer, brown plant hopper, blast, and bacterial leaf blight with a damaged area of 2,365 ha, 3,066 ha, 891 ha, 363 ha, and 1,842 ha every year, respectively (Yogyakarta Institute of Agricultural Plant Protection 2020). However, farmers in Yogyakarta were categorized into the gold category in the utilization of overall pesticides during their farming practices regarding sustainable rice platform (SRP) performance indicators. Using the Field Calculator scoring method based on the number and timing of insecticides, fungicides, herbicides, molluscicide, and rodenticide applications, the scoring of Yogyakarta farmers was, on average, 70% (Devkota et al. 2019). Rice establishment and harvest activities affected labor use, which was high, but labor productivity was low. Roughly 80% of farmers applied puddled transplanted rice and manually harvested it (Devkota et al. 2019). Currently, Yogyakarta is struggling with labor shortages due to increased farmer age and a lack of young people commencing in rice farming.

All of these challenges resulted in variations in rice yield among farmers and created yield gaps. Based on studies conducted by Devkota et al. (2019) and Stuart et al. (2016), farmers’ yield in Yogyakarta was 5.8 t ha−1, with a 42.4% yield gap. The obtainable farm yield (average yield of the topmost farmers) was 9.1 t ha−1. Research and demonstration plots were conducted in Yogyakarta to encourage farmers to improve their farming practices to increase rice yield (Connor et al. 2021b).

2.3.2.2 Rice Situation and Challenges in South Sumatra

The “Musi River Basin” refers to the distribution of tidal land on the east coast of Sumatra Island. In this downstream region, the rivers of South Sumatra flow into the Delta Channel. As a wet ecosystem positioned among an area with a terrestrial system and an aquatic system, characterized by its shallow or flooded groundwater level, this location is a center for rice food production, similar to some other Mega Deltas in South and East Asia (Fig. 2.2).

Fig. 2.2
A location map marks the locations of tidal land on Sumatra Island.

Map tidal land in South Sumatra (provided by the Directorate of Irrigation and Swamp, Directorate General of Natural Resources)

Full size image

There are 362,749 ha of reclaimed tidal land in South Sumatra. The area covered by tidal rice fields is 273,919 ha (BPS-Statistics of Sumatera Selatan Province 2016) or 35.36% of the overall scope of rice fields. This reclamation is a strategic move to enhance the utilization of natural resources to encourage increased food production and rice availability.

Farmers in South Sumatra’s tidal land cultivate rice annually over 131,936 ha, although agronomic cultivation can potentially be conducted twice a year. Some 95,408 ha of tidal lands have been cultivated with paddy twice, 19,226 ha have been grown with other crops, and 27,349 ha remain unplanted (BPS-Statistics of Sumatera Selatan Province 2016). South Sumatra’s harvested paddy area totaled 551,321 ha in 2020, yielding paddy production of 2,743,060 tons, or 1,575,216 tons of milled rice (BPS-Statistics Indonesia 2022c). South Sumatra had a rice surplus of 883,935 tons in 2020 due to its population of 8,467,432 people, with a rice consumption rate of 81.64 kg per person per year.

Utilizing a combined harvester with a leasing system is a viable solution to the labor scarcity that frequently causes harvesting delays. It is more efficient than paying harvest workers, whose consumption costs are substantial. Similarly, land preparation in certain areas, especially on land with overflow, already uses four-wheel tractors, therefore, making land preparation more efficient. Although direct seeding equipment, including tractor-drawn machinery, has been introduced, farmers still prefer the spreading method because it’s cheaper and quicker. A major restraint to a second rice crop has been high rodent and weed infestations. This issue is discussed further in Chap. 4.

The rise in the rice crop** index is expected to enhance possibilities for processing by postharvest organizations; nevertheless, the rice milling unit activity is declining. In addition to the farmers’ time being used in promptly cultivating and replanting the land, the low selling price of grain and rice, particularly during the harvest season, and the lack of drying facilities contribute to the problem of the standard or declining working capacity of rice mills. This problem increases farmers’ interest in selling their products as dry grain. Transport vehicles from outside the province of South Sumatra visit the harvest location or wait at the pier for the paddy to be unloaded from the boat. This situation renders by-products, such as husks and bran, the property of prominent entrepreneurs or factory owners.

Wetlands have the potential to be transformed into agricultural land, but their development faces several challenges. As a result of the marginal and fragile nature of swamp land, large-scale development must be undertaken with caution. The diversity of physicochemical features of the land, such as low soil fertility and pH, poisonous chemicals (aluminum, iron, hydrogen sulfide, and sodium), peat layers, drought/waterlogging, and even seawater intrusion during the dry season, indicates biophysical limitations (Ananto and Pasandaran 2011).

Most tidal land is peat or peat land; in addition to being understood as an ecosystem that must be preserved, it is also considered a resource that may be developed and exploited following the concept of sustainability. Improving the water system in tidal areas for drainage purposes alone will trigger the groundwater level to decline and over-drain. This condition is highly hazardous in wetlands with thin pyrite layers. The raised layer of pyrite that undergoes oxidation will induce an acidification reaction and poison, so restoring it will be difficult or impossible. The paradigm of water management should transform to irrigation-drainage adapted to agricultural purposes. The design of water systems enhances the leaching of hazardous chemicals produced by pyrite oxidation (Ananto and Pasandaran 2010).

2.3.2.3 Rice Situation and Challenges in North Sumatra

North Sumatra is the seventh biggest rice-producing area in Indonesia, with an average productivity of 5.26 t ha−1, which is the same as the national rice productivity in 2021 (BPS-Statistics 2022b). Rice consumption per capita in the year 2020 was 98.28 kg, with a decrease of 1.67% over the last four years (BPS-Statistics 2022a). Based on the trend of the increasing population of North Sumatra over the last 12 years, by 12.70%, it is not comparable with the trend of production, which has decreased by 23.81%. The decline in production for the last 11 years was accompanied by a 34.42% decrease in harvested area. According to the GYGA (2020), the potential for rice production in North Sumatra can reach 9–10 t ha−1, while the average production in North Sumatra is only 5.26 t ha −1, meaning that there is a yield gap of 4–5 t ha−1.

Several programs that have been implemented by the central and regional governments in reducing the yield gap were in the form of seed-independent village programs, special efforts for rice, corn, and soybeans, rice field planting, subsidy for production and agricultural machinery, and other government programs (Girsang et al. 2021). The seed program through seed-independent villages is an easy way to increase rice production. This activity began in 2015 in 25 regencies/cities in order to meet the needs of the region (Department of Food Crops and Horticulture of the Provincial Government 2016). In fact, this activity has not shown significant evidence of increasing production, and the reason is that often the types and quantities of seeds needed during the growing season are not available. This is due to the non-uniform level of knowledge, inappropriate locations, motivation of farmer seed producers, and the low support from the Provincial/District Agriculture Service (Darwis 2018; Directorate of Rice Seeds 2014).

Furthermore, farmers prefer certain varieties, such as Mekongga and Ciherang, although several other varieties have high-yield potential (Mustikawati 2021). The tendency of farmers to use the same variety continuously may trigger changes in the biotype of a pest which will then lead to resistance (Dianawati and Sujitno 2015) and decreased production (Samrin 2018). Likewise, the subsidy of agricultural machinery, such as transplanters, was not able to function properly because of the unskilled human resources of farmers and non-uniform agricultural land. The rapid development of tools in the field, such as the combined harvester used by farmers to date, results in cleaner and cheaper quality rice. It has also accounted for the shortage of manpower for harvesting.

For site-specific nutrient management, farmers use various methods such as soil test kits, integrated katam, and rice consulting services. These tools have helped farmers on a small scale, but the lack of skilled human resources and extension workers and many questions from farmers has led to low use of the tools. The solution that can be offered is increasing the human resources of farmers and extension workers through training, simplification of tools, and more aggressive seed dissemination. Land intensification through the provision of technology that is easily adopted by farmers is a way to answer the challenge of decreasing agricultural land in North Sumatra.

2.3.3 CORIGAP Activities

2.3.3.1 CORIGAP Indonesia

In Indonesia, CORIGAP was a collaborative project between the Indonesian Agency for Agricultural Research and Development (IAARD) and IRRI, and began in 2013, initially involving the Indonesian Center for Food Crops Research and Development (ICFORD), the Assessment Institute for Agricultural Technology (AIAT) South Sumatra, and the AIAT Yogyakarta. It was only in 2017 that AIAT North Sumatra joined CORIGAP.

CORIGAP Indonesia focuses on efforts to close the gap in rice productivity by optimizing the application of existing agricultural research and development innovations. Phase I of CORIGAP was carried out during the period 2013–2016, and starting in 2017, the project entered Phase II (CORIGAP-PRO), which emphasized more on the up-scaling aspect of the application of the best practices recommended from the previous phase. In 2021, CORIGAP Phase 3 was launched to document the lessons learned from implementing best management practices as well as reaching policymakers to ensure sustainable adoption of the BMPs (e.g., Integrated Crop Management in Indonesia) aligned with the country’s national rice program.

Within ten years of CORIGAP implementation in Indonesia, we have conducted many introductory studies and improvements in agricultural technology innovations. Some innovations were implemented in all locations, but some innovations were only suitable for certain agroecological systems. Many agricultural innovations in the form of high-yielding varieties, Integrated Crop Management (ICM), AWD, solar bubble dryers, direct seeding, rodent control with trap barrier systems, hermetic storage bags, semi-automatic downdraft rice husk furnaces, rice husk box dryer, stripper harvester, land laser leveling, combine harvester, and Rice Crop Manager (RCM) were intensely studied by the CORIGAP Indonesia team and applied by cooperating farmers.

In order to increase the benefits of the studies we conducted in the CORIGAP, we formulated the activities of the CORIGAP project in synergy with the national rice programs implemented by the Ministry of Agriculture (MoA). The innovations that are our flagships are included as the subcomponents of national programs implemented by local governments in the three provinces where the CORIGAP project was carried out. Within ten years of CORIGAP’s journey in Indonesia, there are at least three national programs that we have utilized to be the vehicle to deliver CORIGAP interventions.

The first program was GP-PTT or Gerakan Penerapan Pengelolaan Tanaman Terpadu, an integrated crop management implementation program rolled out by the government in 2013–2015. In the program, the main mission was the dissemination and adoption of ICM with an emphasis on the use of high-yielding varieties (HYV) and the arrangement of planting systems using two methods, transplanting in irrigated fields and direct seeding in tidal swamp areas.

The second national program was Upaya Khusus (UPSUS) Padi, a special program to increase rice production that was implemented in 2015–2019, which was the first term of President Joko Widodo’s cabinet. This program was similar to GP-PTT, which carried out the mission of implementing ICM with a focus on utilizing HYV, some decision support system tools such as RCM or Layanan Konsultasi Padi, and improving postharvest handling and optimizing the use of agricultural machinery were also implemented.

The third national approach included two programs: Rawa Intensif, Super dan Aktual (RAISA) and the Selamatkan Rawa, Sejahterakan Petani (SERASI). These programs were specially executed for the development of tidal swamp land. RAISA emphasizes focusing more on mentoring farmers to carry out intensive, super, and actual swamp rice cultivation. Meanwhile, SERASI was more about integrated swamp land optimization for farmer welfare. These two programs for swamplands were implemented in 2018–2020 and are similar to UPSUS. The two programs also promoted ICM as a package of recommended technologies with an emphasis on the use of high-yielding swamp adaptive varieties, dissemination of RCM/LKP use, postharvest handling, and utilization of agricultural mechanization. Layanan Konsultasi Padi (LKP) is an accumulation of rice nutrient management science from IRRI and the innovations developed by the IAARD.

2.3.3.2 CORIGAP Activities in Yogyakarta

The activities of research and demonstration plots were conducted in Yogyakarta to encourage farmers to improve farming practices to increase rice yield and close the yield gaps. Rice technology had a substantial improvement, whereas high-yielding rice varieties, machinery, optimized fertilizer usage, and pest and disease management effectively contributed to the rice farming system. The aim was to reduce the gap between the potential yield attained on experimental activities and the actual yield achieved at farmers’ fields. According to Silva et al. (2022), inefficient fertilizer use and high-rate inputs result in low profitability, which is an aspect that should be of concern in reducing yield gaps. By reducing N fertilizer application to the recommended rate, the increase in rice yield and, therefore, yield gap closure is possibly gained.

Through CORIGAP, Yogyakarta farmers were encouraged to implement ICM to reduce input and improve yields which will improve poverty, preserve the environment, and increase food security. Some elements of ICM, such as HYV, direct planting using drum seeders, transplanter machinery, AWD, RCM, ecologically-based rodent management named PHTT (Pengendalian Hama Tikus Terpadu), and combine harvesters, were introduced to farmers over two years of research in two villages in the Sleman district, and over four years of adaptive participatory activities supported with massive dissemination process in four districts (Sleman, Bantul, Gunungkidul, and Kulon Progo), which reached many farmers. Adaptive participatory activities enriched with an intensive dissemination process were conducted through field schools, field and class training, technical assistants, demonstration plots, field days, farmers cross visits, flyers, television, social media, and online (virtual) training during two years in the COVID-19 period.

Farmers who planted Ciherang as the dominant variety before the CORIGAP project were introduced to alternative varieties like Inpari 10 to Inpari 43 during the CORIGAP project activities. Regarding the labor shortage in Yogyakarta, the drum seeder was introduced. Using a drum seeder, farmers distribute pre-germinated rice seed directly in neat rows with less labor and less time consumption compared to manual transplanting, which requires five women (laborers) with more than 50% higher costs. Mechanical transplanting machines and combine harvesters were also introduced to overcome labor shortages during the peak of planting season and harvest season, as well as to increase labor productivity. A study conducted in East Java by Durroh (2020) showed that the effectiveness of a combine harvester was 58%. Moreover, this machinery gave a 36% impact on the community income with R/C criteria > 1; this means that the revenue was greater than the expenditure. Water management has an important role in increasing rice production and was implemented through AWD. With AWD, the field is permitted to dry out for one or quite a few days and is not continuously flooded (Lampayan et al. 2015). The rice crop manager, an SSNM tool, was introduced to provide better knowledge to farmers about the importance of the appropriate fertilizer rate. According to Stuart et al. (2016), increasing rice yields in Yogyakarta could be achieved by the application of fertilizer using the local recommended rate, for example, a nitrogen rate of 250 kg ha−1, while exceeding this rate would not relate to higher yields obtained. Ecologically-based rodent management was implemented by farmers, in particular in areas which had large damage and were endemic to rodent attack. Increasing farmers’ awareness about yield loss caused by rodents, breaking traditional mindsets (mystic story) about rodents, and encouraging synchronous planting were conducted with great support from Yogyakarta Agriculture Office (Dinas Pertanian Yogyakarta). Promising better yield (50–75% increase in yield) was obtained by farmer groups who implemented ecologically-based rodent management.

2.3.3.3 CORIGAP Activities in South Sumatra

From 2004 until 2022, IRRC activities, followed by CORIGAP, were implemented in the tidal paddy-producing center of Banyuasin Regency in South Sumatra. The aim was to accelerate ICM, support the government’s Rice Special Effort Program (known as UPSUS), and reach 4,500 adopter farmers. As mentioned, tidal swamps covering 273,919 hectares are the second most extensive rice cultivation in South Sumatra. However, the limited availability of human resources requires that farmers adopt various strategies, especially in planting technologies, such as direct seeding. This method causes multiple problems, including slowed rice growth and a rise in pest infestation. Therefore, improvements in planting technology were needed. CORIGAP activities were carried out with the assistance of South Sumatra AIAT by disseminating several superior technologies developed by IRRI and IAARD.

Utilization of new HYV, land leveling with laser leveling techniques (LLL), jajar legowo planting system, rat control with trap barrier system, utilization of AMATOR planting equipment, postharvest technology support in the form of adaptation of dryers powered by rice husk and diesel, and the utilization of a hermetic system for seed storage are examples of the technological innovations applied. The study was implemented in two Banyuasin sub-districts encompassing four villages: Sumber Mulyo, Telang Rejo, Mekarsari (Muara Telang sub-district), and Sidoharjo (Air Saleh sub-district). The rice cultivars include Inpari 22, 33, and 43, which are adapted to tidal marshes. The modification-dragged drum seeder by a hand tractor, AMATOR, is a planting tool developed by Usaha Pelaganan Jasa Alisintan (UPJA), PPL, and South Sumatra AIAT researchers in collaboration. AMATOR is derived from the IRRI drum seeder and a tractor. The results indicated that rice growth and planting time on the AMATOR or drum seeder are faster than on a mechanical transplanter, but their performance is subpar. The mechanical transplanter has the lowest percentage of unfilled grains (10.7%) and the maximum output (6.9 t ha−1) compared to the broadcast seed system, which produces just 4.4 t ha−1 or even less at the farm level. Due to the spacing that gives efficacy and efficiency in plant maintenance, planting tools can even suppress the population of several types of weeds. Optimum plant spacing is essential to maximize the use of sunlight for photosynthesis. The plant acquired a well-balanced growing space due to the appropriate spacing.

Implementing the rodent trap system to control rats proved to be highly efficient in minimizing the possibility of paddy damage by reducing the rat population. Farmers who wish to cultivate rice on tidal land are required to perform rodent management. Initially implemented with a small plot area of traps and early-planted rice, the technique has evolved into a barrier that encompasses the whole expanse of the farmers’ rice fields. Thus, rats are no longer the predominant problem in tidal land (see Chap. 4 for more details).

Although land-leveling technology with LLL causes changes in specific soil physical properties, such as water content, it was demonstrated to increase the total pore space of the soil by 38–50% and decrease the soil density. Bulk density and the entire pore space of soil are crucial in evaluating soil density because soils with high bulk density and low porosity make it hard for plant roots to penetrate. In contrast, soils with low density stimulate root development.

Currently, Banyuasin Regency produces 887,256 tons of rice, making it the regency with the most significant rice production in Sumatra and the fourth most in the country. This accomplishment is remarkable in comparison with other regions dominated by irrigated land.

2.3.3.4 CORIGAP Activities in North Sumatra

Farmers in North Sumatra are still using conventional techniques such as transplanting, habit-based fertilization, using certain varieties continuously, and controlling pests and diseases based on farmer habits. The CORIGAP project was launched in North Sumatra at the end of 2017 in conjunction with the Jarwo Super program. The combination of these two programs disseminated new HYVs and SSNM in the form of rice consultancy services. A total of 108 farmers were involved in this activity consisting of six groups of farmers in three sub-districts which focused on Deli Serdang Regency as a place for Jarwo Super implementation. The reach of best management practice was 120 farmers, consisting of farmers implementing demonstration plots with assistance from extension workers from the Deli Serdang Regency Agriculture Service and AIAT. The training was conducted twice with materials on Jarwo Super technology and rice consulting services. Field meetings with 120 participants were conducted four times during nursery, planting, fertilizer application during active tillering, and after harvesting. In 2018, there were 880 farmers reached by BMP, consisting of 15 farmer groups in ten sub-districts covering three districts: Deli Serdang, Langkat, and Simalungun. There were 126 farmers who conducted demonstration plots consisting of seven groups of farmers in four sub-districts who implemented demonstration plots of Jarwo Super and LKP. The training was conducted four times consisting of land processing and bio-decomposer application, the potential use of new superior varieties in increasing production, LKP, and Jarwo Super technology. Field visits were implemented four times during planting, active tillering, panicle initiation, and harvesting, which were attended by farmers and agricultural extension workers.

In 2017–2018, the focus was on Deli Serdang Regency (Sunggal, Beringin, Lubuk Pakam, Pagar Merbau, Pantai labu, Percut Sei Tuan, dan Tanjung Morawa). In 2019–2020, the focus was on 2000 farmers spread across the Regencies of Batubara, Langkat, Serdang Bedagei, Deli Serdang, Simalungun, Karo, North Tapanuli, and Humbang Hasundutan. Due to the COVID-19 outbreak, a virtual meeting was held by AIAT North Sumatra with the topic of nutrient integration and rice pest control to boost rice productivity in various ecosystems. Participants attending the meeting consisted of researchers, extension workers, farmers, and private companies. The training materials provided to farmers focused on new superior varieties and rice consulting services. The total number of farmers who were reached by BMPs was 1260 in 2019 and 2345 in 2020. In total, 4605 farmers were reached, spread throughout North Sumatra both online and offline. The results achieved from the activity were the use of new HYVs such as Inpari 32, the use of fertilizer recommendations with rice consulting services at rice centers in North Sumatra, fertilization efficiency, and increased production.

2.3.4 Adoption of BMPs in Indonesia

The adoption of drum seeders was seen in 50% of farmers in Yogyakarta during the first phase of the project. However, in 2018, drum seeder was abandoned due to technical difficulties during the wet seasons. High intensity of rainfall made sowing seeds untidy, which affected higher time consumption and labor to replant the growing seedlings. High intensity of rain also meant that seeds pulled apart and were easily visible to birds. This resulted in more seeds being required for re-direct seeding. Farmers’ seed costs increased dramatically due to higher rainfalls and the losses that occurred. Another reason for not using a drum seeder was weed problems. In Yogyakarta, as reported by Devkota et al. (2019), the application of herbicides was not common for rice farmers. As a consequence, the problem of weeds in direct seeding resulted in higher time allocation and laborious activities regarding manual weeding. Farmers described that time limitations and labor scarcities were the foremost motives for ceasing their use of drum seeders. The decision to adopt or not adopt or then re-adopt, even adapt an innovation, is not only determined by farmers’ ability to change but also needs support from the environment (Hellin and Ridaura 2016; Sumberg 2005).

The adoption of new varieties occurred, based on survey results (Connor et al. 2021b), with more than 90% of farmers continuing to plant the improved rice varieties because it was proven that they could increase the yield and close the yield gap (Parhusip et al. 2020). Through demonstration plots, field days and cross-site visits, farmers, as part of the CORIGAP activities, increased their knowledge of several alternative varieties that are suitable for their specific location and showed significant enforcement in the adoption process of new improved varieties. Farmers explained that improved varieties are one of the innovations that are easiest to be applied as long as the seed is available in the market. Moreover, the implementation of improved varieties was relatively cheaper and less time-consuming compared to the implementation of other innovations. This finding is in line with other studies where practices and innovations are adopted by farmers because they are easily applied (Connor et al. 2021c; Wehmeyer et al. 2020).

The adoption of AWD was reported by 50% of surveyed farmers (Connor et al. 2021b). Those who did not adopt the innovation mentioned technical difficulties regarding AWD implementation. Community support was required for the implementation of AWD because it has strong linkages with the Water-using Farmers’ Association (named P3A, Perkumpulan Petani Pemakai Air) and the policy of water usage by the local government and the eligible institution. Field trials and demonstration plots accommodated the adoption process of multifaceted innovations like AWD regarding farmers’ knowledge improvement, which influenced changes (Lampayan et al. 2015; Connor et al. 2021b).

Another innovation which was largely adopted by farmers was ecologically-based rodent management, particularly in the intensive lowland rice fields in Sleman. Farmers recognized the importance of synchronous planting, mass campaigns, habitat manipulation, and a Trap Barrier System (TBS) at their village community level within a 50–100 ha area. In line with a study conducted by Jacob et al. (2010), rodent management suppressed rat abundance at the late crop** phase, which led to a 75% reduction in rat feeding activity and increased yields by 6%.

2.3.5 Development of Mechanization Technologies in South Sumatra’s Tidal Lowlands

South Sumatra uses three technologies: (1) a tub-type Rice Dryer powered with husk energy, (2) a modified drum seeder-type direct seeding machine pulled by a tractor, known as “AMATOR,” and (3) laser-guided land leveling (LLL). The implementation and adoption status of each of these technologies ranged from rapid uptake for husk-powered rice dryers to moderate uptake for the “AMATOR” planting tool to the currently emerging uptake of LLL technology.

To solve the issue of paddy drying in tidal areas, the South Sumatra Forest Fire Management Project (SSFFMP)-European Union supported the design and construction of the ABC model husk furnace with a 3-ton capacity in 2003. Farmers who operated the rice milling unit (RMU) were introduced to the prototype of a drying machine with an “ABC” furnace in 2004 in Upang Village, Makarti Jaya District, Banyuasin Regency (BPTP Sumsel 2007). The semi-automatic husk furnace (d-HRF) type dryer was also introduced in 2013 with a more effective and labor-saving direct heating system, mainly when providing husk material and removing charcoal from burning (Raharjo et al. 2013).

Following the BBS dryer pilot project in Upang Village, 70 units of the BBS dryer box were independently developed in a relatively short period from the 2004 release of the BBS box dryer to the end of 2008. At the end of 2018, more than 500 units had been constructed by farmers/owners of RMU, some of which were supported by the governments of Banyuasin Regency and South Sumatra Province. The Santoso (private sector) workshop in Plaju, Palembang, has expanded the distribution of dryer machines to other provinces and islands, including South Nias and Nias Regencies of North Sumatra Province, Tanjung Jabung Timur Regency of Jambi Province, and Merauke Regency of Papua Province. The rapid spread/adoption of the dryer technology in tidal areas of South Sumatra is due to the following: (1) the technology for drying grain with the BBS box dryer is perceived as a solution to the problems in the field, as it utilizes the husks that have previously been wasted and the resulting husk charcoal can be used as an ameliorant; (2) simple device models can be made locally, and modifications can be made as needed, and (3) researchers facilitate socialization and technical assistance. The findings of a study conducted by Bhandari (2007) in the tidal area of Banyuasin Regency comparing the operation of box dryers with sun drying revealed that if a farmer had 1 t of grains that were processed into gabah kering giling (GKG) (dry unhusked rice) and then sold, it would be more profitable for the farmer to dry it. However, a box dryer is more profitable for the farmer if the grain is processed into rice. It is because when using a box dryer, the proportion of whole rice and head rice is more significant than when field drying and there is an increase in selling price due to the difference in rice quality (Fig. 2.3).

Fig. 2.3
2 photos. First. A few individuals stand inside a flatbed dryer. Second. An exterior view presents 2 hut-shaped establishments.

First pilot project flatbed dryer using husk energy at Upang Village, Banyuasin

Full size image

The direct spread (tabela) crop** method used among farmers in South Sumatra’s tidal lowlands can reduce the amount of work needed for planting. However, the conventional “tabella” system of manually spreading (“sonor”) rice has many weaknesses, such as: (1) seeds do not grow when they drop on the ground of a water-logged rice field (wet sown), (2) high seed rates of more over 60 kg ha−1, (3) irregular spacing, (4) the seeds that are spread are vulnerable to being consumed by bird pests, (5) requires resources for replanting and thinning plants, and (6) susceptible to pests and diseases.

In 2008, the “IRRI drum seeder” type direct seed planting tool (Fig. 2.4) was used in several tidal areas of Banyuasin Regency, South Sumatra, to overcome these limitations. This planting tool was initially created to distribute seeds evenly throughout the field’s surface. The operation is relatively straightforward; seeds are placed into tubes that can hold 2 kg of seeds. When the device is pulled, the seeds flow through the existing holes and form a row of plants. The BPTP Bali built a modified version of the IRRI Drum Seeder that consisted of wood and PVC tubes. The modified drum seeder releases seeds in an array with a gap of 20–25 cm between rows and in a “legowo” row.

Fig. 2.4
2 photographs. First, An individual is rolling a I R R I drum seeder in a dark-soiled field. Second. An individual is using Atabela legowo in a dark, soiled field.

Atabela “IRRI Drum Seeder” (on the left) and Atabela “Legowo” (on the right) (Raharjo et al. 2013)

Full size image

The use of direct seed planting machinery (Atabela) can solve the limitations of the “sonor system,” including reduced seed rates to 35–40 kg−1 ha, regular plant spacing that does not collapse easily, enhanced plant growth, and reduced risk of pests and plant diseases (Raharjo et al. 2013; Maryana et al. 2022). This performance does not necessarily encourage farmers to use “Atabela” widely; additional labor costs (tool operators) and duration of work are the primary reasons, in addition to the expense of tool manufacturing. To improve the effectiveness of the “Atabela” planting tool, they were modified to be dragged by a tractor by incorporating “AMATOR” iron tubes of appropriate diameter. Agricultural Equipment and Machinery Service Business (UPJA) “Agro Assalam” developed the planting devices in collaboration with technicians and field extension officers, which were then manufactured by a local workshop. The redesigned planting tool “AMATOR” was first demonstrated during the 2015 rainy season and is currently widely used in tidal locations, primarily in the Air Saleh Delta and many areas in Banyuasin Regency and in several tidal regions of the provinces of South Sumatra and Jambi. Moreover, AMATOR use has extended to West Java, South Kalimantan, Riau Islands, and North Maluku. The performance measurement shows that AMATOR’s theoretical working capacity is 0.7135 ha h−1 (1,402 h ha−1), and its actual capacity is 0.5244 ha h−1 (1.6012 h ha−1) (Suprihatin et al. 2022) (Fig. 2.5).

Fig. 2.5
2 photographs. First. An individual is using a 2-wheel tractor in a dark, soiled field. Second. A person is using a 4 wheel tractor in a soiled field.

AMATOR operations using 2-wheel (left) and 4-wheel tractors (right)

Full size image

Flatness and topography in tidal swamp influence rice management and yield. Undulating tidal land contour inhibits the production and growth of plants. Farmers use a hand tractor and a four-wheel tractor with a scraper to level the field during plowing. Since 2016, laser-light-guided land-leveling technology (LLL) has been implemented. On May 3–5, 2022, training for service personnel, farmers, extension workers, and researchers, owners of agricultural tools and machinery workshops, and agricultural machinery operators kicked off the project. This exercise is part of a process of continuous learning in the Tanjung Lago District of Banyuasin Regency (Fig. 2.6).

Fig. 2.6
2 photographs of a waterlogged field.

Pum** times are longer with the unequal tide (CORIGAP Photo 2017)

Full size image

2.3.6 The Adoption of Decision Support System “Layanan Konsultasi Padi” in North Sumatra

The technologies that stand out in North Sumatra are the rice consulting service called Layanan Konsultasi Padi (LKP) and the dissemination of HYVs such as Inpari 28, 32, 42. The results of the 2017–2020 period are that LKP and HYVs were introduced through training, demonstration plots, and field meetings. The increase in the production of irrigated lowlands is about 9.9%, and upland rice fields about 52%. The average rice production in North Sumatra is 5.26 t ha−1, which can increase by about 520 kg on average in the demonstration area. The research plots were able to reach 9.46 t ha−1 with the addition of 30 kg of nitrogen after panicle initiation. The use of LKP in North Sumatra has spread among farmers in determining fertilizer recommendations.

Furthermore, the variety Inpari 32 was able to replace Ciherang and Mekongga in almost 70% of rice centers in North Sumatra. This means that the Inpari 32 variety was adopted widely in low to medium-topography rice fields (Parhusip et al. 2020), while for highland rice Inpari 28 was adopted and replaced local varieties with an average production of only 4.23 kg ha−1 (Santoso et al. 2021). The success of this activity is due to the support of the Ministry of Agriculture, local governments, farmer groups, and the private sector. The sustainability of this activity is through the empowerment of village funds for food security in terms of the use of high-yielding varieties that have been introduced and the use of fertilizer recommendations through LKP. Suggestions for improvement for rice consulting services so that farmers can easily adopt them are to add local varieties to the list of varieties as an alternative if there are no suitable varieties for upland irrigated rice fields.

2.3.7 Policy Implication

Indonesia is targeting to become the world’s food granary by 2045 (Sulaiman et al. 2017) and also wants to build independent, advanced and modern agriculture by adopting precision and digital agriculture. The extensibility of agricultural land is one of the determining factors for success in maintaining food self-sufficiency and making Indonesia a world food barn (Mulyani and Agus 2017). In addition, various innovations and technologies that are efficient, environmentally friendly, and easy to implement are urgently needed.

Agriculture 4.0 is an effort to utilize modern Information and Communication Technology to manage agricultural businesses efficiently so that it can support agricultural development as a way to improve the quality and quantity of agricultural production so that it can manage agriculture more precisely. The Ministry of Agriculture has formulated policies related to the rice production system in an effort to realize food security and independence in a sustainable manner, including (a) technological innovations designed and produced are directed to support the improvement of business efficiency and product competitiveness to support the development of agribusiness, (b) research and development activities are in line with efforts to improve the mastery and development of agricultural science and technology, including the use of information technology, as well as other techniques and methods to improve the effectiveness, efficiency, and quality of research results, (c) in order to improve the usefulness and impact of the resulting technological innovations they must be supported by the acceleration of the process and the expansion of the dissemination network as well as innovation feedback to the key actors.

In the nearly ten years of involvement in the CORIGAP project, we identified significant achievements in closing rice yield gaps through the utilization of agricultural innovations tailored to the needs of each participating province (Yogyakarta, South Sumatra, North Sumatra). One of the prominent innovations is the Rice Advisory Service through a website-based application called Layanan Konsultasi Padi (LKP). LKP technology is an accumulation of rice nutrient management science from IRRI and the innovations developed by the Indonesian Agency for Agricultural Research and Development, such as new high-yielding varieties, location-specific planting systems, and pest and disease control, which are formulated into a web-based application. LKP was launched at the end of 2015 and has been evaluated mainly in irrigated agroecosystems. The Ministry of Agriculture follows up on the results of the use of LKP that have been achieved from the CORIGAP project by allocating funds to expand the application of LKP in seven provinces in 2021 and targeting the implementation of LKP as one of the national agricultural programs starting in 2023. The expansion of LKP implementation covers not only irrigated agroecosystems but also rainfed and tidal swamp areas. The potential for expansion to other agroecosystems covers rainfed rice fields of 2 million ha, swamp land of around 35 million ha, and dry land of 7 million ha.

The results of LKP validation activities in seven provinces divided into three agroecosystems: irrigated rice fields, rainfed rice fields, and tidal swamp rice fields show a similar trend where the implementation of LKP recommendations results in higher rice productivity than controls without the implementation of LKP recommendations. Increased rice productivity occurred in each of the three agroecosystems, reaching 31% in irrigated paddy fields, 23% in rainfed paddy fields, and 62% in tidal swamp paddy fields. Based on these positive outcomes, it is highly recommended to encourage the wider use of LKP in areas with sub-optimal land conditions, leading to a great opportunity to leverage higher rice productivity. A significant increase in productivity coupled with the use of more efficient fertilizer inputs will have a great opportunity to increase farmers’ profits.

At the end of 2019, the Ministry of Agriculture established the Agricultural Development Strategic Command (Kostratani) in every sub-district. In its technical implementation, Kostratani involves various technologies based on the Internet of Things, artificial intelligence, and information technology, as well as being connected to the Agriculture War Room. Kostratani is one of the dissemination channels of LKP, especially in supporting the development of advanced, independent, and modern Indonesian agriculture.

The increasing price of fertilizers and the reduction of subdivisions allocated by the government encourage farmers to consider the use of agricultural inputs, especially fertilizers, with the level of yield to be obtained. In this condition, the massive use of equipment/software such as LKP for agricultural extension workers and farmers will be more effective and efficient in the process of diffusion of technological innovations and increasing national rice production. The effectiveness of LKP and the opinions of farmer extension workers and their validation need to be evaluated to continue to improve the use of LKP in the future.

At the end of 2022, the Ministry of Agriculture through the Indonesian Agency for Agricultural Instruments Standardization, IAAIS (previously Indonesian Agency for Agricultural Research and Development, IAARD), held a Rice Crop Manager (RCM) Indonesia Project Inception Workshop with IRRI, the Ministry of Agriculture of the Republic of Korea, the Korean Rural Economic Institute, and the National Development Planning Agency. The workshop was held to consolidate further collaboration between the Indonesian government, IRRI, and South Korea to support LKP implementation in 2023–2025 where the expansion of LKP implementation will be carried out in eight provinces, namely West Java, Central Java, East Java, North Sumatra, South Sumatra, South Kalimantan, Central Kalimantan, and South Sulawesi.

2.4 Vietnam

2.4.1 Rice Production in Vietnam

Vietnam is one of the world’s largest producers and exporters of rice. The country's favorable climate and topography provide a diverse rice production ecosystem. Moreover, its vast network of waterways, particularly the Mekong Delta, provides ample water resources for irrigation, making it an ideal location for rice production. Vietnam also has a large and growing domestic market for rice consumption, providing a stable source of demand for its rice farmers. Finally, its strategic location in Southeast Asia offers opportunities for export to neighboring countries and regions with high demand for rice, such as China and the Middle East. Vietnam’s agricultural area covers approximately 40% (12.39 million hectares) of the country’s total land area (FAO 2019). Rice accounted for around 11% of the agricultural GDP (World Bank 2022). Most rice is grown in the low-lying areas of the Mekong and Red River deltas (Yuen et al. 2021; Yen et al. 2019).

The Mekong River Delta, which comprises 40,000 km2, has around 26,000 km2 area for agriculture and aquaculture and is the primary rice-producing region in Vietnam, accounting for over 50% of the total rice production in the country and 90% of the rice exported (Nguyen 2007; Connor et al. 2021c; USDA Foreign Agricultural Service 2018; Ricepedia 2021). Farmers in the delta Mekong Delta Region can cultivate rice up to three times per year, making it particularly suitable for intensive rice cultivation due to its favorable natural conditions (FAO 2002; GRiSP 2013; Ricepedia 2021).

Vietnam’s rice production increased by 1.48% from 2007 to 2021, reaching 43.85 million metric tons in 2021 (FAOSTAT 2023). During the same period, the total land cultivated for rice production in Vietnam increased slightly by 0.03%, while the yield increased by 1.48%, reaching 6 t ha−1 in 2021 (FAOSTAT 2023). Vietnam has consistently been one of the top five rice producers in the world from 2017 to 2021. It is the second-largest producer in Southeast Asia (FAOSTAT 2023). Consequently, Vietnam was the third-largest exporter of rice in the world in 2021 and 2022, with US$ 2.96 to US$ 3 billion worth of rice exports (USDA 2022). According to the Vietnam Food Association, the country had a 41% year-on-year increase in its rice shipments in the first two weeks of 2023 and earned US$ 115 million (** systems and management practices, and advancements in agricultural technology (World Bank 2022). Additionally, the government of Vietnam has implemented policies and programs to support the rice sector and improve the livelihoods of rice farmers (World Bank 2022).

2.4.2 Transformation of the Rice Industry

In the early years of Vietnam’s history, rice cultivation was primarily carried out by small-holder farmers using traditional methods. However, in the mid-twentieth century, the Vietnamese government began to prioritize agriculture and initiated several policies aimed at increasing rice production. One of the most significant government interventions was the establishment of Agricultural Production Cooperatives (APCs) in the 1950s. These cooperatives were designed to bring together small-scale farmers and provide them with access to resources such as land, equipment, and credit. The APCs were also responsible for redistributing inputs such as seeds and fertilizers and providing technical assistance to farmers (Glewwe et al. 2000).

Collective farming in Vietnam persisted until about the 1990s. It has benefitted both farmers and landless laborers by ensuring subsistence rice cultivation and encouraged the rural population to exchange all other kinds of labor such as repairing thatched roofs, hel** each other with the supervision of children and other non-farm activities. The collective mode of farming in Vietnam survived major socioeconomic and political changes, such as the country’s reunification in 1975, despite facing poverty, stagnant economic growth, and decreasing rice output. However, the collective farming system began to decline in the 1990s due to drastic changes in the rice farming industry, including land reforms and the implementation of new farming technologies and practices. The increase in production and productivity of paddy in Vietnam during the mid-1990s and early 2000s can be attributed to government reforms in land use rights, production decision-making, tariffs, and quotas, as well as the increasing use of fertilizers, pesticides, and high-yielding varieties (Purcell 2011). A momentous transformation took place as farmers’ status transitioned from being tenants or landless to becoming smallholders who owned land (Tuan et al. 2014). This shift in land ownership, coupled with the adoption of innovative technologies, enabled farmers to fulfill their subsistence requirements and ensure food security, consequently expanding their cultivation exponentially. Vietnam’s successful shift in rice farming practices has been reflected in its emergence as one of the top three rice-exporting countries in Asia by 2019.

2.4.3 Constraints and Opportunities in Rice Production

Vietnam’s rapid agricultural development since the mid-1980s has significantly transformed the country, but it has also had considerable ecological, social, and economic impacts that could lead to long-term issues in the twenty-first century, particularly in the context of climate change (ADB 2013). As Vietnam is considered one of the countries to be hit more severely by climate change, it will experience serious implications for economic development, especially in the agricultural sector.

According to a comparative analysis by the World Bank Development Research Group, Vietnam would be the most seriously impacted country in East and Southeast Asia by sea level rise, with almost 40% of the population affected (Dasgupta et al. 2007). Most of the impact is expected in high population density areas, such as the Mekong River Delta (Nguyen 2007). Saltwater intrusion, the irregular intensity of rainfall, and frequent flood occurrences can affect the available period of cultivation, and shortening the crops’ growth period, and reduce yield growth. Furthermore, high levels of salinity in irrigation water coupled with reduced surface water flow could lead to a significant reduction in the total rice cultivation area. Without effective adaptation strategies, the agricultural sector in this region could experience significant losses, which would, in turn, lead to a decline in Vietnam’s overall GDP by 0.7–2.4% by 2050 (Smyle and Cooke 2010). Moreover, intensive crop** patterns such as cultivating rice two to three times per year are likely to decrease in the future, and the performance of high-yielding rice varieties may decline as well (Khang et al. 2010; Rutten et al. 2014; Deb et al. 2016).

Intensive crop** coupled with excessive use of chemical inputs such as fertilizers and pesticides is also a major concern in Vietnam. Several studies have shown excessive use of pesticides, fertilizers, and seeds in the Mekong River Delta (Cassou et al. 2017; Soong 2006; Nguyen et al. 2022). Such practices have a great impact on soil fertility and quality, microbial diversity, rice yield, water quality, the development of pesticide-resistant pests and weeds, and human health (Berg 2001; Nguyen 2016).

Labor shortage is among the constraints in the country’s rice production, which arises from the migration of young people from rural to urban areas in search of better employment opportunities. As a result, the cost of labor has increased, potentially causing a decrease in rice production unless farmers can adapt to these rising costs.

Vietnam’s cost-competitiveness in the rice export sector is unsustainable and may face significant challenges in the future (Eckardt et al. 2016; Lam 2019). While the country’s economic growth model has been centered on boosting agricultural exports for rural development and job creation, this approach has limitations and is no longer sustainable due to rising input costs (Eckardt et al. 2016; Lam 2019). As a result, agriculture’s role in driving rural development and economic growth has diminished.

Overall, it is clear that Vietnam’s agricultural sector faces significant challenges due to climate change, intensive rice production practices, and labor shortage. The government is taking proactive measures to mitigate the risks and impacts associated with the aforementioned constraints. Research and investment in breeding varieties that can compete with the existing rice varieties in the world market were given priority by the government.

2.4.4 CORIGAP Activities in Vietnam

Several studies have shown excessive use of pesticides, fertilizers, and seeds in the Mekong River Delta (Cassou et al. 2017; Soong 2006; Nguyen et al. 2022). It led to the promotion of “Three eductions, Three Gains (3R3G), and subsequently to the promotion of 1 Must Do, 5 Reductions” (1M5R) developed during the 4th phase of the IRRC-IRRI and which was rolled out by the Agricultural Competitiveness Project (ACP) and implemented by the Ministry of Agriculture and Rural Development (MARD) with financing from the World Bank to the Mekong Delta in 2013. 1M5R was certified by MARD as nationally approved best management approaches in the same year. CORIGAP worked with national partners on the “Small Farmers, Large Field” (SFLF) initiative to minimize yield gaps, improve rice production efficiency, and align smallholder farmers more closely with traders and millers. Several fields of individual farmers were consolidated to make larger fields. The boundaries of ownership are maintained with bunds. Each farmer manages their area and strictly follows the 1M5R guidelines to be part of the SFLF (see also Chap. 3). They are also required to buy or use seeds as prescribed by the program, and their paddy is bought right after harvest by participating food companies in the SFLF scheme. Farmers receive 4–5% above market value from the participating companies, while the provincial Department of Agriculture and Rural Development (DARD) provided extension services and monitored which varieties are planted by the farmers. A total of 208 farmers participated in the SFLF cooperatives organized by the Sub-Departments of Plant Protection Services and Crop Production under provincial DARD. Mushroom production at the village level was a new initiative in Can Tho and Long An in 2013. The said initiative was aligned with the national directive not to burn rice straw and to provide jobs to displaced women through the rapid adoption of mechanical thresher-harvesters.

Field trials were set up in the second half of 2014. The adaptive research and field calculator were combined to compare the sustainability performance of good agricultural practice (GAP), SFLF, and regular farm practice. The development of business models for better straw management and strengthening of extension on market integration of mushroom production were accomplished in 2014.

Farmer participatory field trials were established in Can Tho to identify and demonstrate the best practices for different crop establishment practices, including drum seeding, manual broadcasting, blower seeding (using a seed broadcasting machine), and mechanical transplanter. Mechanical fertilizer spreaders and combine harvesters, as well as paddy dryers, were also demonstrated. All best agricultural practices, including VnSAT standards for 1M5R, such as AWD and activities to reduce postharvest losses, were also demonstrated through field trials. Rice straw management using a baler and mushroom production were promoted.

2.4.5 Adoption of CORIGAP Technologies and Documentation of Changes

In the mid-2000s, the Three Reductions, Three Gains (3R3G) (see Chap. 4), and later 1M5R integrated practice and technology packages were introduced in various provinces of the Mekong River Delta, reaching over 130,000 farmers to date. The promotion of 1M5R recommendations has been the focus of the CORIGAP project in Vietnam, with a particular emphasis on the provinces of An Giang and Can Tho. The spread of 1M5R to other provinces in the MRD has been facilitated via a World Bank-funded project, “Vietnam – Sustainable Agricultural Transformation (VnSAT).”

Several studies have focused on the adoption of 1M5R. In the study by Wehmeyer (2021) on the adoption and diffusion of agricultural best management practices through the CORIGAP project in Vietnam, the most commonly adopted technologies in rice production were AWD, combine harvesters, drum seeders, and improved rice varieties. With these technologies, most farmers were able to reduce their input usage and achieve higher rice yields. However, during the CORIGAP project, farmers using 1M5R recommendations used significantly fewer inputs than control farmers, resulting in lower productivity levels. Despite this, the project showed that farmers were able to maintain profitability by reducing input costs, achieving yield consistency, and ensuring livelihood stability by producing rice more sustainably.

A study by Connor et al. (2021c) examined the factors affecting the adoption of sustainable rice farming practices in the 1M5R program and identified adoption constraints among 465 farmers in An Giang and Can Tho Province. While most farmers followed pesticide and postharvest loss reduction requirements and the use of certified seeds, they faced difficulties reducing fertilizer use, water use, and seed rate due to implementation challenges and weather conditions. Ease of implementation, education, satisfaction, and non-rice income were the main drivers for adopting the whole package, while the ease of implementation and non-rice income drove the adoption of individual requirements with lower rates. Adoption monitoring and continued extension services are needed to overcome physical barriers and ensure successful implementation.

Similarly, Tuan et al. (2022) investigated 1M5R adoption barriers with 155 farmers qualitatively conducting 17 focus group discussions. The study has shown that external factors such as the geographical location of farms and access to water seem to be the main barriers. Furthermore, knowledge provision, demonstration fields, and access to extension services were most important in increasing the adoption of sustainable rice farming practices.

2.4.6 Conclusions

The CORIGAP project in Vietnam has significantly promoted sustainable rice farming practices through the 1M5R integrated practice and technology package. The project has successfully reached over 130,000 farmers in various provinces of the Mekong River Delta, with a particular emphasis on the provinces of An Giang and Can Tho. Studies have shown that farmers who adopted 1M5R recommendations could reduce their input use by using technologies such as AWD, combine harvesters, drum seeders, and improved rice varieties, as shown in Wehmeyer et al.’s (2022) study. These practices led to higher rice yields, improved profitability, and ensured livelihood stability.

However, the studies have also highlighted the challenges farmers face in reducing fertilizer use, water use, and the reduction of seed rate, as well as external factors such as geographic location and access to water, which can hinder the adoption of sustainable rice farming practices (Connor et al. 2021c). Despite these challenges, the project has identified several drivers for adopting the whole package, including ease of implementation, education, satisfaction, and non-rice income. Tuan et al. (2022) found that knowledge provision, demonstration fields, and access to extension services were most important in increasing the adoption of sustainable rice farming practices.

The project has also emphasized the need for continued adoption monitoring and extension services to ensure the successful implementation of sustainable rice farming practices since they help to overcome physical barriers and ensure successful implementation.

The CORIGAP project has demonstrated the importance of promoting sustainable rice farming practices and providing farmers with the necessary resources and knowledge to adopt these practices effectively. The project’s success in reaching many farmers and improving their productivity and profitability underscores the importance of continued efforts to promote sustainable agricultural practices in Vietnam and beyond.

2.5 China

2.5.1 Rice Production in China

With about 9% of the world’s arable land, China has been able to feed nearly 20% of the world’s population or 1.4 billion people (Xu et al. 2021). Rice plays a very important role in maintaining China’s food security. China is the largest rice producer and consumer in the world, with average annual rice production and consumption accounting for about 30% of the world. The annual rice planting area is 30 million hectares. More than 60% of China’s population depends on rice as their staple food. Guangdong, with a population of 127 million, is one of the major rice-producing provinces in China (Xu et al. 2021). Rice is the most important food crop in Guangdong, with 1.8 million hectares of planting area, accounting for 80% of food crop area and production. However, due to limited farming land, the food self-sufficiency of Guangdong is less than 30%. Guangdong Province was the focus of CORIGAP activities in China.

2.5.2 Challenges Facing Rice Production in China

Guangdong is a relatively highly developed province in China. In the 1990s, rice production in Guangdong as well as in China, was facing a number of challenges. Fertilizer nitrogen (fertilizer N) input was quite high, while nitrogen-use efficiency (NUE) was very low. On average, the total fertilizer N input was 194 kg N ha−1 in Guangdong, but the recovery efficiency of N was only 24%. A huge amount of N fertilizer was lost to the environment resulting in serious non-point source pollution. Moreover, the overuse of N fertilizer, in combination with the warm and humid climate, made the rice crop more susceptible to diseases and insect pests, and farmers had to spray more pesticides to avoid yield loss. Furthermore, lodging prevails and causes heavy yield loss, especially in the coastal regions with frequent typhoons. The grain yield of rice was only 5.8 t ha−1 and 16% lower than the national average. The profit of rice production was quite poor as a result of low grain yield and high input costs. More recently, water shortage, labor shortage, environmental pollution, and greenhouse gas emissions became new challenges for rice production with the development of social economy and urbanization.

2.5.3 CORIGAP Activities in Guangdong China

A series of studies and extension activities were conducted to solve the problems facing rice production. From 2001 to 2012, the Guangdong Rice Research Institute (GDRRI) developed the “3 controls” technology (3CT) in cooperation with IRRI. Compared with farmers’ practice, 3CT can reduce N fertilizer input by about 20% while, at the same time, increasing grain yield by about 10%. The recovery efficiency of fertilizer N is increased by 10%. Occurrence of sheath blight, plant hopper, leaf roller, and other diseases and pests is significantly reduced, and hence, pesticide application can be reduced by one to three times per season. Lodging resistance is substantially improved (Zhong et al. 2010). The 3CT technology has been recommended to rice farmers by the Ministry of Agriculture and Rural Affairs of China and the Department of Agriculture and Rural Affairs of Guangdong, Jiangxi, and Hainan provinces. The 3CT technology has been widely used in major projects such as the high-yield creation, demonstration of super rice, agricultural non-point source pollution control, and reduction of fertilizer and pesticide use. Since 2013, with the support of the CORIGAP project and other projects in China, GDRRI carried out two aspects of work. The first was the research and development of low-carbon and high-yield cultivation technology (LC), and the second was the demonstration and large-scale dissemination of the 3CT and the LC technologies.

For the development of LC technology, GDDRI first introduced safe alternate wetting and drying (safe AWD) technology from IRRI. Secondly, the safe AWD was integrated with the 3CT technology to establish the LC technology. Compared with farmer’s practice (FP), the 3CT technology can save nitrogen fertilizer by 20% and increase grain yield by about 10%. Compared with 3CT, the LC technology can save water by 20%, reduce methane emissions by 20–30%, and reduce N and P loss to the environment by 50%. In 2017, the LC technology was recommended to rice farmers as one of the key technologies for low-carbon development by the National Development and Reform Commission of China.

The 3CT and the LC technologies were then promoted to large-scale use in Guangdong and other parts of South China. Field trials, demonstrations, and training courses were carried out. The performances of the new technologies were reported by newspapers, TV programs, websites, WeChat, and other media. The implementation of the CORIGAP project was combined with various national and provincial projects or actions, including the agricultural non-point source pollution control project jointly supported by the World Bank and Guangdong provincial government.

2.5.4 Case Study of Development and Implementation of 3CT and Low-Carbon Technologies

2.5.4.1 Case 1: On-Station Comparison of Grain Yield, Greenhouse Gas Emission, and Nitrogen Losses Under Different Crop Management in Guangzhou

In the early and late seasons of 2016–2017, field comparison trials were conducted at the Dafeng Experimental Station of the Guangdong Academy of Agricultural Sciences in Guangzhou. The experimental field is located in the Tianhe District of Guangzhou and is characterized by the humid subtropical monsoon climate. The main physical and chemical properties of the soil are pH 6.0, total N 1.62 g kg−1, available N 82.6 mg kg−1, available P 40.4 mg kg−1, available K (Potassium) 58.7 mg kg−1, and organic matter 41.4 g kg−1. A hybrid rice variety, Tianyou 3618, was transplanted at a plant spacing of 20 cm × 20 cm with two seedlings per hill. There were three crop management treatments arranged in a randomized complete block design with three replications. The three treatments were as follows:

  1. 1.

    FP. Fertilizer N in the form of urea was applied at a rate of N 180 kg ha−1 for the early season and N 200 kg ha−1 for the late season. In total, 40% of fertilizer N was applied as basal one day before transplanting, 20% was top-dressed at 3–5 days after transplanting (DAT), 30% at 8–10 DAT, and 10% at 18–20 DAT. Fertilizer P was applied in the form of calcium superphosphate as basal at 45 kg P2O5 ha−1. Fertilizer K was applied in the form of potassium chloride at 135 kg K2O ha−1, with 50% applied as basal and 50% at panicle initiation. After transplanting, a 2–5 cm water layer was kept for tillering until the tiller number (including main stem and tillers) reached 80% of the targeted panicle number, followed by midseason drainage for about 20 days to suppress excessive tillers, and then, a 2–5 cm water layer was maintained during the whole heading stage. A shallow water layer was maintained during grain filling until seven days before harvest when final drainage was implemented.

  2. 2.

    3CT. The technical procedure of “three controls” technology was employed (Zhong et al. 2010). Fertilizer N was applied in the form of urea at 150 kg ha−1 for the early season and 180 kg N ha−1 for the late season, with 40% as basal, 20% at mid-tillering (15 DAT), 30% at panicle initiation (35 DAT for early season and 30 DAT for late season), and 10% at heading. The application of P and K fertilizers and water management was the same as FP.

  3. 3.

    LC. The application of N, P, and K fertilizers was consistent with 3CT. AWD was used for water management. Field water depth was kept at 2–5 cm during the first 10 DAT to allow the seedlings to recover and suppress weeds. Perforated field water tubes were installed to monitor the water level below the soil surface. The timing of irrigation was based on the water depth in the field water tube installed in the field to a depth of 15 cm. When the water disappeared in the tubes, the plot was irrigated to a depth of 3–5 cm above the soil surface. At the beginning of the heading date (when 1% of the panicles had emerged from the leaf sheath of the flag leaf), the field was re-flooded for seven days, and hereafter, the AWD cycles were repeated until terminal drainage, which was imposed seven days before harvest.

The 3CT and LC technologies had higher grain yield, less irrigation water input, lower greenhouse gas emission and N loss, and greater water productivity than FP for both early and later seasons (Table 2.1). Compared with FP, 3CT increased grain yield, reduced greenhouse gas emissions and N loss to the environment, and increased water productivity. Irrigation water input was comparable for 3CT and FP. Compared with 3CT, the LC technology significantly reduced water input, greenhouse gas emission, and N loss and increased water productivity. The grain yield of 3CT and LC technologies was comparable. On average, the grain yield of 3CT was 13.1 and 14.7% greater than FP for the early and late seasons, respectively. The LC technology had a slightly higher grain yield than 3CT. Irrigation water input was comparable for FP and 3CT. However, the LC saved 82.5 and 36.0% of irrigation water for early and late seasons, respectively, compared to FP. Greenhouse gas emission (including CH4 and N2O) under 3CT was 6.9 and 5.0% lower than that under FP in the early and late seasons, respectively. The LC technology further reduced greenhouse gas emissions by 24.6 and 33.3% for early and late seasons, respectively, in comparison with 3CT. Compared to FP, the 3CT reduced N loss by 32.2% for the early season and by 31.6% for the late season. The LC further reduced N loss by 16.9% in the early season and 12.4% in the late season based on 3CT (Liang et al. 2017, 2019).

Table 2.1 Grain yield, irrigation water input, greenhouse gas emission, N loss, and water productivity under different crop management in the field experiment at Guangzhou during the 2016–2017 early and late seasons
Full size table

In South China, the climate is hot and humid with abundant rainfall, and the nutrient N and P runoff and N volatilization loss of paddy fields are serious. The large amount and improper timing of water and fertilizer input in FP have caused non-point source pollution. Compared with FP, the 3CT and LC technologies can reduce N fertilizer input and hence reduce N loss from ammonia volatilization, runoff, and leaching. The LC technology reduced irrigation water input and improved the water storage capacity of the rice field, and therefore, the runoff loss of N was further reduced compared to 3CT.

2.5.4.2 Case 2: On-Farm Demonstration of 3CT and Low-Carbon Technologies for Transplanted Rice at Gaoyao County, Guangdong Province

From 2016 to 2019, demonstrations of 3CT and LC technologies were carried out in Gaoyao County of Guangdong Province. The demonstration plot was located in Baitudong Village, Lubu Township, with an area of 167 ha. The demonstration site belongs to the subtropical monsoon humid climate zone, with an annual mean temperature of 22 ℃, an annual accumulated effective temperature of 7,905 ℃, and annual rainfall of 1,700 mm. The paddy soil contained 26.8 g kg−1 of organic matter, 1.98 g kg−1 total N, 116.0 mg kg −1 available N, 25.3 mg kg−1 available P, and 51.6 mg kg−1 of available K.

In the demonstration area, comparison trials with three treatments and three replications were set up. The three treatments were:

  1. 1.

    FP. Total fertilizer input was 202 kg N ha−1 (in the form of urea), 45 kg P2O5 ha−1 (in the form of calcium superphosphate), and 113 kg K2O ha−1 (in the form of potassium chloride). Nitrogen fertilizer was applied with 40% as basal, 20% at the rooting stage, 30% at early tillering, and 10% at the late tillering stage. All phosphorus was applied as basal. Potassium was applied at the proportion of 50% as basal and 50% at the late tillering stage. Conventional water management was adopted, with a 2–5 cm water layer maintained in the field during the whole growth season except for the midseason drainage to suppress unproductive tillers.

  2. 2.

    3CT. Total fertilizer input was 135 kg N ha−1, 45 kg P2O5 ha−1, and 113 kg K2O ha−1. In the early seasons, nitrogen fertilizer was applied with 50% as basal, 20% at mid-tillering (MT), and 30% at panicle initiation (PI). In the late seasons, fertilizer N was applied with 40% as basal, 20% at MT, 30% at PI, and 10% at heading. All phosphorus and 50% of potassium were applied as basal. Another 50% of potassium was applied at PI. Water management was the same as FP.

  3. 3.

    LC. Fertilizer management was the same as 3CT. The alternate wetting and drying technology (AWD) was adopted for water management. Field water depth was kept at 2–5 cm during the first 10 DAT. Irrigation was done whenever the water disappeared in the water tubes installed 15 cm below the soil surface, and a 3–5 cm water layer was resumed. Terminal drainage was imposed seven days before harvest.

As shown in Fig. 2.7, both 3CT and LC technologies improved grain yield and profit compared to FP. In the early season, the number of irrigations was lowest in LC. Compared to the FP, grain yield of 3CT and LC was significantly increased by 11.5 and 11.4%, while production costs for 3CT and LC were significantly decreased by 11.1% and 11.7%, respectively (p < 0.05). The number of irrigations was reduced by 0.4 and 0.8 (9.3 and 18.6%) for 3CT and LC. Profit was significantly increased by 429 US$ ha−1 (35.8%) and 441 US$ ha−1 (36.8%), respectively (p < 0.05). In the late season, the number of irrigations in LC was significantly decreased by 41.6% and 46.6% (p < 0.05), respectively, in comparison with FP and 3CT. The advantages in the late season were similar to that in the early season regarding grain yield, cost saving, and profit. The water saving in the late season was much greater than that in the early season (Zhong et al. 2022). As the water storage capacity of the field is improved in LC, the number of runoff during rainfall is significantly reduced, which lays a foundation for reducing non-point source pollution. In addition, the occurrence of sheath blight, leaf roller, plant hopper, and other diseases and pests in 3CT and LC was also significantly lower than in FP. The main reason is the reduced unproductive tillers which help to improve the microenvironment of the canopy. Water saving also reduced the humidity between rice plants, which favored inhibiting the propagation and transmission of pathogenic bacteria.

Fig. 2.7
4 bar graphs with error bars plot the numbers of irrigation, grain yield, production cost, and profit for F P, 3 C T, and L C. Each graph has 6 bars. a. and b. The maximum number of irrigation and production cost is for F P. c. and d. The maximum grain yield and profit are for 3 C T.

Number of irrigations (a), production cost (b), grain yield (c), and profit (d) of early and late season rice under farmer’s practice (FP), three controls technology (3CT), and low-carbon and high-yield technology (LC) in the on-farm demonstration conducted at Gaoyao County of Guangdong Province during 2016–2019. Data in the figure are means of the four years of 2016–2019. The different lowercase letters indicate significant differences for treatment at p < 0.05 by one-way ANOVA (LSD test)

Full size image

The new technologies 3CT and LC have been warmly welcomed by rice farmers. The main incentive for farmers to adopt the new technologies is the higher and more stable grain yield, lower costs of fertilizer and pesticides, and, most importantly, improved profit. Furthermore, farmers can save labor and cost for irrigation, which is very important in the western part of Guangdong, where water shortage prevails, especially for late season rice. The new technologies have also been welcomed by officials of different levels who pay more attention to environmental protection and public welfare because the new technologies can effectively reduce greenhouse gas emissions and non-point source pollution and improve food safety, biodiversity, and sustainability of rice production. As more and more farmers adopt and keep adopting new technologies, the above-mentioned benefits will become increasingly noticeable.

2.5.4.3 Case 3: On-Farm Demonstration of 3CT and Low-Carbon Technology for Direct-Seeded Rice at Lianjiang County, Guangdong Province

Lianjiang County is a traditional direct-seeded rice production area located in the coastal area of western Guangdong. Grain yield is quite low (about 20% lower than the national average) and unstable in that area due to frequent typhoons and improper crop management, for example, high seeding rates and the overuse of N-fertilizers. On-farm demonstrations of 3CT and LC technologies were conducted during 2018–2020 at Yunxia Village, Yingzai Township, Lianjiang County. Soil properties at the demonstration site are as follows: pH 5.28, organic matter 14.65 g kg−1, total N 0.69 g kg−1, total P 0.41 g kg−1, total K 10.33 g kg−1, available N 72.49 mg kg−1, available P 35.30 mg kg−1, and available K 89.36 mg kg−1. A high-quality inbred rice variety Baixiang 139 was used. There were three treatments:

  1. 1.

    FP. The total amount of fertilizer applied was 240 kg N ha−1, 45 kg P2O5 ha−1, and 240 kg K2O ha−1. Before sowing, 25% of N and 50% of P were applied as basal. At 15 days after sowing (DAS), 45% of N, 25% of P, and 25% of K were applied. At 25 DAS, 30% of N, 25% of P, and 75% of K were applied.

  2. 2.

    3CT. Total fertilizer input was 165 kg N ha−1, 50 kg P2O5 ha−1, and 135 kg K2O ha−1. A compound fertilizer with 24% of N, 7% of P2O5, and 19% of K2O was applied with 50% as basal, 20% at mid-tillering, and 30% at PI.

  3. 3.

    LC. Total fertilizer input was 150 kg N ha−1, 45 kg P2O5 ha−1, and 120 kg K2O ha−1. The compound fertilizer with 24% of N, 7% of P2O5, and 19% of K2O was applied with 40% as basal and 60% at PI, respectively.

The plot size for each treatment was about 1300 m2 with three replications. The seeding rate for each treatment was 75 kg ha−1. For FP and 3CT, seeds were allowed to emerge in moist soil, and a 2–5 cm water layer was added and maintained when the seedlings grew to the 3-leaf stage. When the number of tillers (including main stems) reached about 300 m−2, the field was drained until the top second leaf was exposed, and then, a 2–5 cm water layer was restored and maintained until heading. The field was kept moist during grain filling until seven days before harvest when the final drainage was done. For LC, AWD irrigation technology was adopted.

The demonstration showed that the 3CT and LC technologies significantly increased rice grain yield and net income and reduced fertilizer costs and the number of irrigations. Compared with FP, 3CT saved 31.3 and 43.8% of N and K fertilizers while increasing 11.0% of P fertilizer. The LC technology reduced N, P, and K fertilizers by 9.1%, 10.0%, and 11.1%, respectively, in comparison with 3CT. The 3CT and LC technologies had 1.7 and 4.0 fewer irrigations than FP, respectively. Production costs were 10.1 and 17.1% lower for 3CT and LC than FP, respectively. Grain yield was 22.9% greater for 3CT and LC than that for FP. With higher grain yield and lower production cost, the 3CT and LC technologies increased net income dramatically in comparison with FP. The net income of 3CT was 747 US$ ha−1 or 168.64% greater than FP. The LC technology further increased net income by 135 US$ ha−1 or 11.3% based on 3CT. In addition, the reduction of irrigation water input in the LC technology should have benefited the environment and farmers’ livelihood due to its reduced methane emission and N loss to the environment (Zhong et al. 2022).

The demonstration results showed that 3CT and LC technologies performed well not only in transplanted rice systems but also in direct-seeded rice systems. Labor shortage and low profit are major challenges facing rice production in Guangdong as well as in China (Table 2.2). As labor costs increase, more and more rice farmers shift from transplanting to direct seeding. However, lodging is a major problem for direct-seeded rice. The 3CT and LC technologies are advantageous in lodging resistance and have been proven to be very helpful for farmers to achieve high and stable yields and hence profit in direct-seeded rice production. Therefore, the increase in direct-seeded rice will further stimulate the adoption of 3CT and LC technologies in the future.

Table 2.2 Grain yield, production cost, net income, and number of irrigations of direct-seeded rice under different crop managements at Lianjiang County, Guangdong Province, during 2018–2020
Full size table

2.5.5 Farmers’ Adoption and Perceptions of 3CT

In 2019, we conducted a study on farmers’ adoption and perception of 3CT in Guangdong Province. We implemented a cross-sectional survey questionnaire with 142 farmers (see Chap. 7 for more information) from six villages that were randomly selected by the local partners (Wehmeyer et al. 2020). The study was conceptualized focusing on three different impact factors: economic, social, and environmental. The findings show that all interviewed farmers adopted the 3CT. However, it needs to be noted that all farmers were part of a World Bank project that also promoted the 3CT. Farmers perceived benefits and changes in all three impact areas of sustainable development. Farmers reported having higher yields and reduced input costs. They felt that their health had improved and perceived to have gained better social and human capital. It became apparent that the longer farmers had been using 3CT, the more benefits they perceived, indicating that monitoring and evaluation of project outcomes need to be conducted in appropriate time frames. The Chinese farmers did not yet perceive changes in biodiversity since the timeframe was probably not long enough to see real effects on faunal population growth. However, the study showed that 3CT is highly appreciated by farmers due to its effectiveness, ease of use, and compatibility with their farming needs. The study highlighted that 3CT not only works in closely monitored field trials but also performs well in farmer fields (Wehmeyer et al. 2020).

2.6 Sri Lanka

2.6.1 Rice Production in Sri Lanka

Sri Lanka is a small island (65,610 km2) in South Asia surrounded by the Indian Ocean. The geography of the country includes coastal plains and hills and mountains in the interior. Sri Lanka has a population of around 22 million and is a multinational country with diverse cultures, languages, and ethnicities. It has a documented history of over 3000 years, and rice cultivation has been evident since then. Being the staple food of Sri Lankans, rice plays a vital role in the country’s agricultural sector. The paddy production and productivity have increased during the past 50 years up to the level of self-sufficiency since 2010 due to the introduction of high-yielding, improved varieties, advanced technologies, increased fertilizer usage, and land expansion. The average annual per capita consumption of rice is about 108 kg, while the demand for rice is increasing gradually due to an increase in population, shifting of food habits from wheat flour to rice, and increasing demand for other rice-based products.

2.6.2 Challenges Faced in Rice Production

A wide yield gap exists between the potential yield of varieties and farmers’ actual yield in Sri Lanka. About 24% of the yield gap (1.3 t ha−1) is prominent in the major rice-growing districts such as Polonnaruwa district, while the yield gap reported in the dry zone was around 50% (Devkota et al. 2019). Poor productivity is recorded in the rainfed areas and in some of the minor irrigation systems due to poor crop management practices such as improper pest, disease, and especially poor weed and nutrient management. Furthermore, frequently occurring unfavorable weather conditions, such as severe droughts that Sri Lanka experienced in years 2014 and 2017, are another cause of the wide yield gap.

Current rice yields across the world’s main rice-growing areas are approaching the highest crop yield that a farmer can attain using conventional technologies. Sri Lanka is no exception, and yield stagnation can be observed in several regions. In Sri Lanka, the rice productivity is about 4.3 t ha−1, which remained at a plateau during the last ten years (except for 4.8 t ha−1 recorded in the year 2019). Despite the limited genetic and agronomic improvement possible for rice, increasing the production and maintaining the level of self-sufficiency could be a big challenge with limited or diminishing land and water availability and with unfavorable weather conditions.

Deficiencies of soil nutrients due to the long-term cultivation of rice without soil rehabilitation remedies are evident in many parts of the country. In addition, the government policy banning the use of chemical fertilizers in 2021 drastically reduced rice productivity by about 40% and severely threatened the country’s self-sufficiency. Though the policy was revised in 2022, the effect is continued even at present due to the limited availability of chemical fertilizers to rice farmers. Inappropriate land preparation techniques, such as primary land preparation using the rotary plow, poor attention to water management, continued use of chemical fertilizers, lack of organic matter incorporation, and changes in weather patterns, enhance the depletion of soil nutrients further.

Weeds are the most disastrous biotic stress in rice cultivation in Sri Lanka, causing an average of 30–40% of the yield loss if not controlled. Since 95% of the rice cultivated in Sri Lanka is direct-seeded, weed infestation is a menace and difficult to control without having intensive integrated approaches. Weed infestation raises production costs and diminishes crop quality. The diverse weed flora in rice systems contributes to increased yield gaps and hence reduces the national rice production considerably. Among the weed species, weedy rice, Ischaemum rugosum, Echinochloa crus-galli, and Cyperus species contribute to a significant yield loss. Weed density of 50 weeds m−2 accounts for the 38% yield loss in rice (Herath et al. 2018). Further, the presence of Ischaemum rugosum biomass significantly contributes to yield losses (r = 0.84***) which is higher compared to other weed species.

Weedy rice types are also spreading at an alarming rate in most rice-growing agroecological zones of the country (Rathnasekara 2015). Weedy rice contributes to significant yield loss depending on its density in the field. Some farmers with weedy rice-infested areas experienced that 300–350 weedy rice m−2 contribute to 100% yield loss. A high density of weedy rice causes more competitiveness to rice; further tallness of weedy rice causes lodging incidences and combined, these factors can be responsible for total yield loss in rice. Weedy rice control has become an immense challenge for rice farmers in Sri Lanka due to its similarity to cultivated rice, long-lasting seed dormancy, its seed-shattering nature, and massive soil seed bank enrichment. The lack of a selective herbicide for the control of weedy rice or other effective measures has made its control a subject of national significance.

Drought, high temperatures, floods, and salinity are the major abiotic stresses causing yield losses in rice in Sri Lanka. Due to the severe drought reported in 2017, approximately 2.4 million tons (46.1%) of production was lost, recording the lowest paddy production over the last decade (CBSL 2017). Soil problems such as bog and half bog soils, iron toxicity, and acidity in the wet zone also reduce the productivity of rice considerably.

Recently, rice production in Sri Lanka was considerably decreased due to the shortage of synthetic fertilizers and other inputs such as herbicides and fuel. Though fertilizer became available in 2022, the shortage in the first half of the 2022 season and unaffordable prices were detrimentally affecting the yield. For example, the price for 50 kg of urea increased from Rs. 500.00 (US$ 1.55) to Rs. 25,000–40,000.00 (US$ 77–US$ 124).

The use of machinery and chemicals, including herbicides and pesticides, is increasing with the expansion of paddy cultivation, creating high production costs. Meanwhile, labor charges are very high due to the shortage of labor during the peak cultivation period. In each season, the cultivation period starts in parallel in all paddy tracks, and therefore, there are only a limited number of laborers available. Due to land fragmentation over generations, most of the paddy plots in Sri Lanka are small and irregular in shape. This increases the cost of management, inefficiency in machinery use, and the reduction of the net area.

2.6.3 Introduction of CORIGAP Activities

The CORIGAP activities in Sri Lanka aimed to promote the delivery of best management practices on a large scale that reduce yield gaps and improve the profit of smallholder farmers in irrigated lowland rice systems. The project activities were initially implemented in two major rice-growing districts, i.e., Polonnaruwa (North-Central part of Sri Lanka) and Kilinochchi (Northern part). After 2015, the activities were also expanded to Kurunegala, Hambantota, Anuradhapura, Vauniya, Mulathive, and Ampara districts, which are also major rice-growing districts in Sri Lanka. These activities benefited more than 20,000 farmers by the end of the year 2021.

Initially, a baseline survey in Polonnaruwa and Kilinochchi districts was conducted to identify the socioeconomic background and the existing yield gap in 2014. In Polonnaruwa, the average land size per farmer was 0.81 ha. Wet direct seeding into puddled soil was practiced at a rate of 80–100 kg seeds/ha. The use of herbicides, both pre- and post-emergence, to control weeds was common. The average yield of a farmer was 5–6 t ha−1, and the profit was around Rs. 50,000 ha−1 (approximately US$ 155). The average yield of the top 10% of farmers was 6.3 t ha−1, while the average yield of the average farmer was 4.9 t ha−1. The size of farm holding in Kilinochchi varied between 2 and 15 ha, and all farmers practiced dry seeding. Based on the survey results and to resolve the challenges with national importance, the following activities have been initiated since 2014.

Dry row seeding: Dry row seeding was demonstrated in Polonnaruwa and Kilinochchi districts to test an alternative method to overcome the disadvantages of random seeding. In Polonnaruwa, seeding depth could not be maintained at optimum level as there were large soil clots. As plots were irregular, rows were not straight, and some areas were left without seeding. A small strip along the bund was also left out without seeding. Thus, the establishment was poor and irregular in all plots. Farmers did not want to keep the crops and started to puddle the plots under wet conditions about two weeks after seeding, which coincided with the time they started land preparation. In Kilinochchi, a yield advantage of 0.7 t ha−1 was recorded in line sowing by using a multi-crop seeder compared to farmers’ practice of manual broadcasting. In addition, there was a saving in seed costs due to savings in seed rate (50 kg ha−1 was used in line sowing compared to 100 kg ha−1 recommended in direct-wet seeding). Hence, the introduction of row seeding with a row seeder into the existing farming system in Polonnaruwa as an alternative crop establishment method is not possible due to poor yield and non-acceptance by farmers, but it has a potential to use in the Kilinochchi district due to comparatively higher yield than that of conventional wet direct seeding.

Adaptability testing of new rice varieties and establishment methods for rice cultivation: Demonstrations were conducted in Polonnaruwa, Kurunegala, and Kilinochchi districts to popularize Bg 370, a newly released high-yielding variety and Zhonghua, a promising high-yielding variety with better characteristics. Several demonstrations were conducted, presenting seedling broadcasting and mechanical transplanting to show the advantages of these methods. Demonstrations showed that both seedling broadcasting and mechanical transplanting reduced pest and disease incidences while increasing the yields by 10–20% compared to direct seeding. However, farmer adoption of these methods is still lacking due to some technical barriers.

Plot combining and land laser leveling: Paddy plot combining involved the amalgamation of small irregularly shaped plots into large regular-shaped plots to increase machinery use efficiencies and profitability in rice farming while minimizing labor costs for bund preparation. A lot of activities and demonstrations were conducted related to paddy plot combining and land laser leveling in most of the rice-growing districts in Sri Lanka. In the Polonnaruwa district, this was initially practiced to evaluate the feasibility of the practices and to estimate their impact on the net area, crop establishment, and efficiencies of field operations. Plot combining could recover 4% of paddy lands and reduce the labor requirement for bund preparation from 12 man-days ha−1 to seven man-days ha−1 (saved five labor requirement ha−1) (Illangakoon et al. 2020). It also increased input-use efficiencies (e.g., fuel, time in land preparation and harvesting). In the Kurunegala district, the consolidation of plots resulted in a 3 to 5% increase in land area by reducing the number of bunds. It also saved labor associated with bund management by 3.3 man-days ha−1. Identifying the importance of this activity, the Department of Agriculture has initiated a mega program of plot combining to reach 600 farmers covering all rice-growing districts of the country. A survey on plot combining revealed that it increased yield and farmers’ income by 10.4% and 15.1%, respectively, and reduced costs of cultivation by 11.5%. A study to identify farmers’ perceptions of benefits revealed that almost all farmers gained several benefits from participating in the activity and having positive perceptions of land consolidation of their paddy lands (Rambodagedera et al. 2022). The major benefits were the improvement of paddy lands productivity, improvement of the time due to minimizing bund maintenance, machinery and labor efficiency, the addition of a few more hours to farmers’ spare time in a busy day, comfort during harsh farming operations, and easiness in weed management. Land laser leveling was also demonstrated in Kurunegala and Trincomalee districts, and the farmers were satisfied because of easy water management, uniform plant growth, and high yield on their paddy plots. In addition, making field canals to convert water from one field to another was simple and more cost-effective. The loss of harvest in the rice field has also been reduced in larger plots when harvesting was done using combined harvesters.

Development of an agronomic package for mechanically transplanted rice: Suitable rice varieties, suitable planting distances, seedlings per hill, and planting depth were evaluated for the self-propelled walk-behind type of mechanical transplanter. All medium-duration varieties (110–135 days) and most of the short-duration rice varieties (100–109 days), such as Bg 406, Bg 379-2, Bg 403, Bw 367, Bg 366, Bg 357, and At 362, were identified as suitable for mechanical transplanting (Illangakoon et al. 2017). The possibility of using 12–16 cm spacing levels, 4–6 seedlings/hill, and 1.5–2.5 cm depths in mechanical transplanting depending on the age of varieties and existing soil type was highlighted. Nursery management practices in mechanical transplanting were also optimized. A nursery mixture comprised of topsoil and compost at a 1:1 ratio, 0.5 kg of seed paddy m−2 of nursery bed, and 12 days old seedlings for transplanting were identified as the optimum for mechanical transplanting. There was no yield reduction in mechanical transplanting compared to other crop establishment methods, while it yielded comparable to seedling broadcasting (Illangakoon et al. 2018). In addition, mechanical transplanting had the potential to produce 6–7 t ha−1 under best management practices. Therefore, mechanical transplanting was identified as a feasible option in rice cultivation and a suitable agronomic package for mechanical transplanting was developed.

Adaptability testing of establishment methods: Farmer participatory research was conducted in the Mullaitivu district to compare row sowing by seeders, mechanical transplanting, and parachute and direct seeding methods (Sivaneson and Ponnegipprenthiraraja 2018). Mechanical transplanting and the parachute method produced a higher number of effective tillers, higher spikelet number per panicle, and higher filled grain percentage and grain yield compared to direct seeding. The demonstration highlighted the possibility of using mechanical transplanting and the parachute method for rice cultivation in the Northern region of the country.

Integrated weed management (IWM) solutions: IWM practices were demonstrated to achieve efficient weed management. It included the use of weed-competitive rice varieties and the use of pre-emergent herbicides. Furthermore, information was identified and generated for integrated weed management programs in rice-based crop** systems. A survey was conducted with 300 farmers in Hambantota district. The study revealed that 95% of farmers in the Hambantota district depend on herbicides to control weeds. Significant knowledge gaps in relation to the selection of correct herbicides, dosage, time of application, and application methods existed.

Weedy rice management package: Proper land preparation practices, application of pretilachlor herbicides, weedy rice seed bank management, and different establishment methods (transplanting, parachute, and broadcasting) were used to manage weedy rice in infested areas of Hambantota and Ampara districts. Proper land preparation practices and reduction of weedy rice seed bank, application of pretilachlor herbicides before crop establishment, and row transplanting resulted in a 90% reduction of weedy rice and a 23% yield increase in rice. A weedy rice seed bank is the number of weedy rice seeds available in the different depths of soil after seed shattering. The continuous seed shattering of weedy rice increases the number of seeds available in the soil in a particular area. For example, topsoil up to 20 cm depth comprised of weedy rice seeds, which led to difficulties in controlling weedy rice. The application of pretilachlor herbicides before field establishment provided excellent control of weedy rice. Transplanting and the parachute establishment managed the occurrence of weedy rice by more than 75%. Proper land preparation, including five times plowing, has been shown to reduce the weedy rice seed bank level and resulted in a reduction of more than 50% soil of the weedy rice seed bank.

Herbicide usage and Herbicide resistance studies: Herbicide use increased tremendously during the last decades, and thus, malpractices of herbicide application also increased. Herbicide mixing practice was more popular among the farmers in the Hambantota district, where most farmers (87%) mix two to three herbicides before the application, while 13% use a single application of herbicides. The study identified the most popular unspecified fifteen-tank mixing of herbicides. Bispyribac sodium 40 g/1 + metamifop 100 g/1 SE + carfentrazone-ethyl 240 g 1EC−1 was the most popular unspecified tank mixture among the majority of farmers (20.3%). Furthermore, the majority of farmers used hand sprayers (66%), while 34% used power sprayers for herbicide application (Herath et al. 2017). Due to the increase in the misuse of herbicides among farmers, the study highlighted the need for awareness and multiple approaches to weed management in rice (Herath et al. 2017).

Herbicide resistance in weed development is a common phenomenon in herbicide dominance systems. A study reported that the three main modes of action herbicide group popular among the farmers in Sri Lanka with protoporphyrinogen oxidase-inhibitors (PPO), ALS-inhibiting herbicides, and acetyl CoA carboxylase (ACCase) inhibitors (Herath et al. 2017). It also revealed the poor efficacy of herbicides on Cyperus diformis and Ischamum rugosum. Cyperus difformis developed resistance to 2-methyl-4-chlorophenoxyacetic acid (MCPA) and bispyribac sodium 40 g/l + metamifop100g/lSC. The ED50 values from the dose–response experiments indicated that the R biotype of Cyperus difformis was 1.95 times more resistant to MCPA than susceptible ones. The R biotype was 2.4 times more resistant to bispyribac sodium 40 g/l + metamifop100g/l SC than the S biotype (Herath et al. 2017). Furthermore, some populations of I. rugosum showed a moderate level of resistance against bispyribac sodium 40 g/1 + metamifop 100 g/1 SC (Herath et al. 2019).

Water management: Alternative Wetting and Drying (AWD) is a water-saving technology in rice cultivation. In AWD practice, irrigation is started after 2–3 weeks of crop establishment, and then, the field is allowed to drain off until the water level goes down to 15 cm below the soil surface. This procedure is repeated until the flower initiation. After flower initiation, the water level is maintained continuously around 0–5 cm until two weeks before the expected date of harvesting. Demonstrations on AWD were conducted in Polonnaruwa and Kilinochchi districts to monitor water levels in rice fields and also to convey the importance of water saving in rice cultivation for farmers. Farmers were able to save four irrigations during the crop** season, and farmer awareness on water saving in rice cultivation was initiated. However, the partnership with the irrigation department was identified as important to control water release as per AWD criteria. AWD was also demonstrated in Hambantota district in 2018 and Anuradhapura district in 2019 at a large scale, and it was found that 20–30% irrigation water could be saved using this practice.

Characterization of water quality and effects of pesticide use: Detailed field studies on water quality with a strong focus on monitoring pesticide presence were completed in the Deduru Oya River Basin. The study was an SDC-funded PhD project under CORIGAP. This, at a landscape level, was the first study of its type in Sri Lanka. The occurrence of twenty commonly used pesticides was monitored. The findings indicated that many pesticides were used between 1.2 and 11 times the recommended use. Of major concern was the detection of high levels of 2‐methyl‐4‐chlorophenoxyacetic and diazinon in irrigation water. Refer to Jayasiri et al. (2022a, b) for details of the design and findings of this impressive research.

Awareness programs on best management practices (BMP): Several awareness programs were conducted to make farmers aware of the BMPs. They included training programs, field days and field visits, demonstrations, TV and radio programs, newspaper articles, videos, news bulletins, and web pages. Programs included proper land preparation techniques and crop establishment methods, plot combining and laser leveling, nutrient management, weed and weedy rice management, pest and disease management, and water management. More than 20,000 farmers were reached with these awareness programs to adopt BMPs in rice cultivation.

2.6.4 Conclusions

Plot combining to enhance agricultural efficiency had a very high impact on reducing yield gaps. The elimination of micro-parceling and curved boundaries of rice fields and the readjustment of plots with correct configuration made farm operations easier and more profitable. It also increased machinery use, harvesting efficiencies, and farmers’ income by more than 10% and profit by more than 15% in lowland irrigated rice cultivation. Studies on weeds, weedy rice, and herbicide resistance and training programs created great farmer awareness of correct practices in weed management. The adoption of integrated weed and weedy rice management packages minimized the yield loss due to weeds and weedy rice significantly.