Microbial Secondary Metabolites: Effectual Armors to Improve Stress Survivability in Crop Plants

Abstract

Biotic and abiotic stresses are the foremost limiting factors in agricultural productivity and cause extensive losses to crop production. Microorganisms are ubiquitous in nature and successfully colonize diverse natural environments. Secondary metabolites production is testimonial to enormous biosynthetic capabilities of microorganisms and can be a potential partner in modulating local and systemic defense mechanisms in plants under adverse external conditions. Inoculating plants with root-colonizing nonpathogenic bacteria can significantly increase tolerance against abiotic stresses such as salinity, drought, metallic toxicity, and bioprotection against biotic stresses apart from acting as biocontrol agents. Increasing climatic alterations, crop losses, and environmentally unfriendly chemical pesticides made it imperative to explore the underlying integrated processes of plant-microbe interactions. Multiomics approaches including transcriptomics, proteomics, metabolomics, and genomics are providing the deeper insights into the microbial-mediated stress tolerance in plants and are inevitable to understand for implementation in the fields. This chapter highlights the significance of plant growth–promoting bacteria as the effective tools for environmentally friendly resource management to improve crop production for sustainable agriculture. Beneficial bacteria-mediated stress management in plants comprises several biochemical, physiological, and morphological mechanisms, and understanding of these cross-protection microorganisms is highly valuable in agriculture systems under the stress of climatic change.