Microbial Consortia for Sustaining Productivity of Non-legume Crops: Prospects and Challenges

Soil micro-organisms play a pivotal role in food production through their significant effects on nutrient transformation and release, soil organic matter and carbon dynamics, and biotic and abiotic stress tolerance to plants. The microbial consortia (MC) are mixtures of two or more microbial species/strains, living together symbiotically. Generally, a consortium of micro-organisms performs better than the inoculum of single microbial species. The MC, specifically plant growth-promoting rhizobacteria and biofilm biofertilizers can be used in non-legume cereal crops grown in a large area of the world. The MC may help in solubilization of plant nutrients from the soil native pool, production of beneficial substances (siderophores, hormones, etc.) for better root growth of non-legume crops and reduction in plant growth retarding hormone(s). The MC research focuses/encompasses, mainly legume crops, although there are prospect and substantial evidences of their use in non-legume crops. Reports indicate that the use of MC can enhance micronutrients, total organic carbon and N in soil. They could fix N, solubilize P and K, improve soil physico-chemical properties and act as phyto-stimulator. Globally, almost 50% of the total N, P and K used in crops are consumed by cereal crops, which are heavy feeder with high yield potential. Integration of MC with chemical fertilizers provides enormous scope for increasing nutrient-use efficiency in accordance with harmonious improvement in crop yield and soil health. The MC as a component of integrated nutrient management in non-legume cereal crops would considerably reduce the demand and use of mineral fertilizers and cost of cultivation and save nutrient for use in other crops of economic importance. They are low-cost and eco-friendly options and can improve soil health vis-a-vis enhancing productivity of non-legume crops.