The effects of P on wheat root-associated prokaryotic communities are dependent on soil P content, growth stage and variety

Abstract Background Wheat root-associated microbes play an indispensable role in helping plants obtain phosphorus (P) from soil. However, it is not clear how the effects of soil P on microorganisms vary with growth stage and variety. Therefore, revealing the interactive effects of soil P content, growth stage and variety on wheat root-associated microorganisms, which is important for further improving the P absorption strategy of plants. Methods Three wheat varieties were selected for pot experiment under three levels of soil P content, and sampling at seedling, flowering and mature stage, respectively. Using 16S rRNA gene profiling, we investigated the relative contribution of compartment niche, growth stage, variety and soil P content and their interaction effects on wheat root-associated prokaryotic communities. Results Wheat root-associated prokaryotic community assembly was mainly shaped by compartment niches. For each compartment niche, growth stage had higher contribution to the variations of prokaryotic communities than soil P content and wheat variety. The effects of P content on the prokaryotic communities varied by growth stage and variety. Meanwhile, the effects of wheat variety were also influenced by growth stage and soil P content. It is worth mentioning that low P content exacerbated the variation of prokaryotic communities among varieties. Conclusions This study revealed the interaction of host selection and soil P content on root-associated prokaryotic communities. The effects of soil P on wheat root-associated prokaryotic communities are dependent on P content, growth stage and variety. Our study provides a fundamental understanding on the relationship between soil P content and microorganisms.