Abstract

 Rhizospheric soil is enriched with diverse microbial communities, which give rise to sophisticated plant-microbes interactions via chemical communication. The bacteria attain communication through quorum sensing and lead to biofilm formation, developing connections between the cell density, and altering gene expression. Such processes include diffusion and accumulation of signal molecules such as autoinducer i.e. acyl-homoserine lactones, Autoinducer-2 (AI-2), QS pheromone, etc. in the environment and trigger the expression of the gene. Due to increment in cell density, bacteria produce the substances that inhibit the growth of pathogens, fix nitrogen and optimize nodule formation. Moreover, the adaptability of microbial communities under stress conditions directly/indirectly was correlated with host plant growth. The plants and soil microorganisms equally face the abiotic stresses and may cause environmental tolerance and adaptability via complex physiological and cellular mechanisms. The recent knowledge of the plant-microbe relationship and their communication mechanisms can be helpful in the development and commercialization of agricultural practices to improve desired crop health and productivity under various abiotic and biotic stresses. This chapter explores such habiting microbial communications in rhizosphere attributing to soil environment in various means.