Rhizosphere microbiome: revisiting the synergy of plant-microbe interactions

Sustainable enhancement in food production from less available arable land must encompass a balanced use of inorganic, organic, and biofertilizer sources of plant nutrients to augment and maintain soil fertility and productivity. The varied responses of microbial inoculants across fields and crops, however, have formed a major bottleneck that hinders its widespread adoption. This necessitates an intricate analysis of the inter-relationships between soil microbial communities and their impact on host plant productivity. The concept of “biased rhizosphere,” which evolved from the interactions among different components of the rhizosphere including plant roots and soil microflora, strives to garner a better understanding of the complex rhizospheric intercommunications. Moreover, knowledge on rhizosphere microbiome is essential for developing strategies for shaping the rhizosphere to benefit the plants. With the advent of molecular and “omics” tools, a better understanding of the plant-microbe association could be acquired which could play a crucial role in drafting the future “biofertilizers.” The present review, therefore aims to (a) to introduce the concepts of rhizosphere hotspots and microbiomes and (b) to detail out the methodologies for creating biased rhizospheres for plant-mediated selection of beneficial microorganisms and their roles in improving plant performance.