Revealing the structure of phyllosphere microbiome in rice leaves infected by Magnaporthe oryzae

Background/Question/Methods

The soil-plant system hosts enormous epiphytic, symbiotic and pathogenic microbes. Previous evidence suggests that soil microbiota within rhizosphere play an important role in regulating pathogenic infections of plants. Vast microbes also colonize the surface of plant leaves, the phyllosphere, potentially influencing the growth and health of their host plants. Yet, little is known about the structure and function of microbiota in the phyllosphere.

In this study, we investigated the role of the phyllosphere microbiome in regulating the infection of foliar fungal pathogen Magnaporthe oryzae on leaves of rice plants (Oryza sativa) in a rice-fish co-culture system. We used Illumina Miseq to sequence 16S ribosomal RNA gene amplicons for DNA prepared from leaf samples with or without disease infections. 

Results/Conclusions

Results from sequencing and multivariate statistical analysis showed that leaves infected with fungal pathogens had a significantly distinct bacterial community in comparison with healthy leaves. Microbial communities on healthy leaves also differed significantly from those in the healthy part of infected leaves. Among detected class, healthy leaves had a lower relative abundance of Alpha-, Gamma- and Betaproteobacteria, but a higher abundance of Anaerolineae, Actinobacteria, Deltaproteobacteria and Nitrospira compared with infected or healthy parts of infected leaves. These findings highlight the importance of the function and structure of phyllosphere microbiome in understanding the biological underpinnings of plant disease infection and control.