Responses of bacterial phoD gene abundance and diversity to crop rotation and feedbacks to phosphorus uptake in wheat

Abstract

Crop rotation can increase crop productivity and suppress disease. However, current understanding of responses of soil functional microbial communities to agricultural management practices is limited. Here, we conducted a field experiment to investigate the impact of crop rotations, fertilization regimens, and wheat variety on rhizosphere functional communities involved in phosphorus (P) cycling. Rotation altered the composition of phoD-harboring bacteria in the wheat rhizosphere. The rare taxa of Roseivivax was enriched in the Soybean (Glycine max (L.) Merr.)-Wheat (Triticum aestivum L.) (SW) rotation, whereas Hydrogenophaga was enriched in the Maize (Zea mays L.) -Wheat (Triticum aestivum L.) (MW) rotation. However, fertilization regimens (high and low N, P and K fertilizers) in the soybean/maize season and wheat variety (Jimai 22 and Shannong 28) had no impact. SW rotation increased phoD gene abundance, and the latter was significantly negatively correlated to available phosphorus (AP) content. Hydrogenophaga was positively with wheat biomass (p < 0.05), whereas, Roseivivax was negatively with P uptake (p < 0.01). The rare genera may play important roles in soil organic P mineralization. Our findings highlight the importance of assessing phylogenetic responses to rotations and subsequent ecosystem services under long-term rotations, and then improve our understanding of the interaction among plant, soil, and microbiome.