Phyllosphere Microbiome: Functional Importance in Sustainable Agriculture

Abstract Plants are recognized as metaorganisms because they harbor highly complex, diversified, and distinctive microbial communities which are symbiotically associated with each other and modulate the physiological activities of each other directly or indirectly. From plant-associated microbial community studies, hundreds of microbial species are found to inhabit different plant microenvironments such as the rhizosphere, phyllosphere, and endosphere. The plant microbiome is the key determinant of plant growth and health management by modulating plant physiological processes under different environmental conditions. Over the years, the coevolution of the microbial communities along with their plant hosts made the scientific community realize the importance of understanding the mechanism of plant-microbe interactions for the benefit of human civilization as well as environmental stability. The phyllosphere represents one of the most vibrant and dynamic inhabitants of different microbiotas and governs the different physiological processes at the interface between plants, microorganisms, and the atmosphere. Insight analysis and studies on the dynamics of the plant-associated phyllospheric microbiome and their implications could set off new dimensions to the strategies of sustainable agriculture such as the development of microbial inoculants as biofertilizers for plant growth and development and improved crop yield, improved nutrient mobilization and quality management, biocontrol agents for induced systemic resistance against phytopathogens, or stress-resistance mechanisms to overcome various biotic and abiotic stress conditions. This chapter aims to provide the dynamics of the phyllospheric microbiome, its role in sustainable agriculture, and its widespread avenues.