Mixed irrigation affects the composition and diversity of the soil bacterial community

Water resource shortage has become an important factor limiting agricultural sustainability in China. In addition, the development and utilization of unconventional water resources are greatly important for alleviating agricultural water resource deficit. The Pakchoi was cultivated by using the surface soil (0–20 cm) from the field in this pot experiment. The experiment lasted for approximately 1 month to study microbial community structure variation under brackish water and reclaimed water irrigation. The 16S rDNA high-throughput assays revealed that soil bacteria mainly consisted of Proteobacteria and Actinobacteria at the Phylum level, along with Arenimonas and Nocardioides at the Genus level under mixed irrigation with brackish water and reclaimed water. In summary, irrigation with pure reclaimed water promoted part of microbial communities and irrigation with pure brackish water inhibited the growth and activities of certain microbial communities. We found that mixed irrigation improved the microbial community structure diversity compared with that in response to pure brackish water irrigation, while decreased the community structure diversity compared with that in response to fresh water irrigation and pure reclaimed water irrigation.