Plant Movements

Abstract

Terrestrial plants are sessile, and yet they can sense their environment and can respond to sensory information through visible movements to optimize their survival, growth, and reproduction. Charles Darwin published his findings on the phenomenon of phototropism in his book entitled “The Power of Movement in Plants”, published in 1880. Plant movements can be defined as the changes in the spatial orientation or conformation of an organ or its parts. Plant movements include movements toward light, opening and closing of flowers, growth of develo** roots in search of water and nutrients, etc. In fact, inflorescence, fruits, and shoots are all capable of moving by sensing changes in environment thereby adjusting their position, function, and behavior accordingly. Plant movements are extremely slow. Classical examples of visible plant movements include the response of sensitive plants like ‘Touch-me-not’ (Mimosa pudica) and the carnivorous Venus’ flytrap (Dionaea muscipula). In addition to whole organ, the movement of single cells is also possible which includes, for example, the movement of guard cells which regulates the stomatal pore size, as well as growth of the pollen tube through the style. Such movements are caused by motor cells driven by changes in pressure from within the cells exerted against the cell walls. Pressure causes changes in the dimensions of individual cells or tissues which results in distinctive movements. Plant movements are classified as