Role Of Ethylene And Plant Growth-Promoting Rhizobacteria In Stressed Crop Plants

Ethylene is a gaseous plant growth hormone produced endogenously by almost all plants and plays a key role in inducing multifarious physiological changes in plants at molecular level. Endogenous production of ethylene is accelerated substantially in response to biotic and abiotic stresses which adversely affects the root growth and consequently the growth of the plant as a whole. Certain plant growth promoting rhizobacteria (PGPR) contain a vital enzyme, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which regulates ethylene production by metabolizing ACC into a-ketobutyrate and ammonia. Inoculation with such PGPR could be helpful in sustaining plant growth and development under stress conditions by reducing stress-induced ethylene production. In this chapter, all aspects of such PGPR regarding alleviation of "stresses imposed effects" on plants will be discussed.