- Soil Science & Conservation 10
- Plant Physiology 8
- Plant Sciences 8
- Agriculture 6
- Ecology 4
- Environment, general 4
- Environmental Physics 4
- Plant Anatomy/Development 4
- Plant Ecology 4
- Plant Systematics/Taxonomy/Biogeography 4
- Science, Humanities and Social Sciences, multidisciplinary 2
- Science, multidisciplinary 2
- Virology 2
- Biological Microscopy 1
- Life Sciences, general 1
- Microbiology 1
- Mycology 1
- Parasitology 1