Phyllosphere and Its Potential Role in Sustainable Agriculture

Abstract

The Phyllosphere – the microbial composition of the aerial part of the plant – has coevolved with its plant host to populate one of the highly dominated places microbes are able to colonize. In contrast to root associated microbes which are engulfed by a buffering soil, the phyllosphere microbial community is highly affected by environmental factors such as climate variation. Considering the high diversity and abundance of foliar community consisting bacteria, fungi, protozoa and nematodes, the phyllosphere is subjected to complex ecological interactions (e.g., antibiosis, competition for resources, and symbiosis) among its members and the plant host. Similar to observation in human gut microbiome, these interactions are likely to affect plant interaction with pathogens, as partially demonstrated in studies of biocontrol agents. Thus, “Plants wear their guts on the outside” as previously suggested by Janzen DH (1985) The natural history of mutualisms. In: The biology of mutualism: ecology and evolution. Croom/Helm, London/Sydney, pp 40–99. In spite of the importance of this community, there are limited studies that deploy functional omics approaches to study the phyllosphere, and specifically the microbial biotic community associated with pathogenic organism - the Pathobiome. Thus, future studies should include functional analysis of the phyllosphere, role of its community members as biofertilizers and growth stimulators, the effect of nutrients (e. g., K, N, P, Fe) composition on its microbial population profile, and phyllosphere-host interactions. Empowered by “next generation sequencing”, findings from these studies should enable to support agrotechnical practice and breeding programs that will improve crops production, quality, and resistance to biotic and abiotic stress.This chapter covers most important facets of knowledge accumulated from phyllosphere research: Environmental conditions affecting the establishment and composition of the phyllosphere. Advanced methodologies used for detection and study of the phyllosphere, following summary of its taxonomic composition. The role of the phyllosphere in plant fitness and health, including study of the pathobiome. And finally, the potential use of phyllosphere monitoring and manipulation in sustainable agriculture practices.