Wheat-root associated prokaryotic community: interplay between plant selection and location

Abstract

Root-associated microbiomes are important for plant nutrient uptake, disease suppression and plant growth. It is important to reveal wheat-root associated microbial community assembly and dominant drivers determining their variability. Using 16S rRNA gene profiling, we investigated the effects of sample type, location, growth stage and variety on prokaryotic communities in the root endosphere and rhizosphere of wheat and bulk soil based on the field samples including 5 varieties from 4 locations along similar latitude with the distance about 157 to 800 km apart between any two locations. Prokaryotic communities were more diverse in the bulk soil and rhizosphere than in root endosphere. Wheat-root associated prokaryotic community assembly was shaped predominantly by sample type, while within each sample type, location had stronger effects on the variation in prokaryotic community than growth stage or variety. Wheat variety effects varied substantially among different locations and growth stages in root endosphere and rhizosphere samples, and the variety effects were location-specific and growth stage-specific. Root endosphere specially enriched Pseudomonas, relative to other two sample types, while rhizosphere mainly enriched Bacillus. This study characterized prokaryotic communities of wheat-root endosphere and rhizosphere and their relationships, and demonstrated significant interactive effects between wheat variety, location and growth stage on prokaryotic community assembly in field condition.