Soil Microbes in Plant Growth Promotion and for Mitigation of Abiotic Stress of Drought

Abstract

A large proportion of world’s agricultural land is becoming less productive or completely unproductive due to different environmental factors. Drought is one of the major agriculture constraints which is caused by insufficient rainfall, prolonged and frequent dry spells or changes in rainfall patterns. Drought impairs growth, water relations and water use efficiency of plants, which further alters their morphological, physiological and biochemical activities. Crop growth models predict that occurrence and intensity of drought will be more severe in future. In the current scenario, to meet global food demands, various strategies have been formulated to cultivate the crops under drought-affected area. Among them, the use of different microbial community could be a viable strategy, which enables plants to combat with water stress through various direct and indirect ways. The use of microbial inoculation for drought stress management is considered as cost-effective and more eco-friendly approach than traditional methods. Various rhizospheric soil microbes, including arbuscular mycorrhizal (AM) fungi, N-fixing bacteria and plant growth promoting microbes (PGPMs), help in stress resistance and better plant performance. PGPMs represent a broad range of archaea, bacteria and fungi, which are having excellent root association ability to produce different enzymes and metabolites for various abiotic stress tolerances. In the present chapter, the exploration of potential soil and root microbiome and their mechanism of actions for drought tolerance in relation to better plant growth and development have been discussed.