Plant-microbe communication: New facets for sustainable agriculture

Abstract

Nowadays, sustainable agriculture is the need of the hour as it necessitates increasing plant productivity without causing much disturbance in the environment. In principle, regression in crop production has been attributed to several environmental vagaries including water deficit conditions, saline stress, and heavy metal (HM) stress. Sustainability of any agroecosystems depends on plant-microbe communications that operate in the rhizosphere where microbial biota including both saprophytes and mutualistic symbionts exist. Among them, plant growth-promoting rhizobacteria (PGPRs) and arbuscular mycorrhizal (AM) fungi are designated as biofertilizers due to their multifunctional traits including soil stabilization, nitrogen fixation, nutrient recycling, phytohormone synthesis, and upregulation of defense responses in plants when subjected to stress conditions. At the rhizospheric level, such microorganisms interact intensely with host roots as well as among themselves, thus leading to the successful establishment of the microcosm environment of mutable activities. This chapter documents and highlights (1) the physical and chemical communication that assists in the functioning of root microbiota and (2) the potential role of multifaceted microbes (PGPRs and AM fungi) in stimulating plant growth and development under stressed environment.