Mechanism Of Maintaining Diversity Of Endophytes In Plant Leaves

Plant leaf endophytes are asymptomatic bacteria and fungi that infect living tissues of plants and survive therein without producing any visible symptoms of their infection.Endophytes form communities in living plant tissues,and the composition of different endophytic communities will affect plant growth,nutrient absorption,immunity and ecosystem function.Due to the limitation of plant species and spatial and temporal scales,there is a lack of comprehensive and in-depth understanding of the factors affecting the composition of leaf endophytic communities.In this study,with the Chinese Academy of Sciences institute of botany introduction decades of plants in greenhouse,using the amplification high-throughput sequencing technologies,at the time of sampling position of greenhouse as a contemporary environmental factor,introduction time and introduction area as historical factors,explored the host plants,microenvironment and historical factors for endophytic bacterial and fungal community structure of the plant leaf.The results showed that the phylogeny of plant host was the key factor affecting the community structure of leaf endophytes,and the diversity and relative abundance of leaf endophytes were significantly different among host plants of different families.Plant phylogenetic distance was significantly correlated with the composition of endophytic bacterial community,but not with leaf endophytic fungi,which might be due to the phylogenetic conservatism of leaf endophytic fungi,host plants,or both.Historical factors,i.e.,time of introduction and region of introduction,had significant effects on ? diversity of endophytic fungi and ? diversity of community composition of plant leaves.There was no significant correlation between historical factors and community composition of endophytic bacteria,but there was a significant correlation between time of introduction and dissimilarity of endophytic fungi in different plant hosts.Microenvironment,i.e.,different greenhouse locations of host plants,had significant effects on ? diversity and community composition of endophytic bacteria in plant leaves,but had little explanation for ? diversity.The microenvironment of the host plant significantly affected the community composition of endophytic bacteria and endophytic fungi in the leaves.Both endophytic bacteria and endophytic fungi were more likely to respond to the environmental changes of the host plant.In general,the plant host and microenvironment in this study determined the community composition of endophytic bacteria and fungi in plant leaves,and the influence of historical factors was not significant.In this study,a large amount of plant samples from greenhouse plants introduced for decades were used to clarify the factors affecting the diversity and community composition of endophytic bacteria in plant leaves.