Abstract:To deeply understand the effects of different moisture and straw addition on the composition, structure and diversity of soil microbial phosphorus cycling functional gene communities in paddy fields, typical paddy soil in Jianghan Plain was selected as the research object. Four treatments were set up including simulated dry land, dry land with straw addition, paddy field and paddy field with straw addition. The samples were incubated at a constant temperature of 25 ℃ for 30 days. The community composition and diversity of soil bacteria and fungi and the responses of dominant bacterial groups to changes in soil moisture and straw addition were analyzed by using Illumina Miseq high-throughput sequencing technology. The results showed that the richness and diversity of bacterial communities in simulated dry land were higher than those in paddy fields; while the richness and diversity of fungal communities in simulated paddy fields were higher than those in dry land. Straw addition was conducive to increasing the richness of soil phoD gene communities, while moisture had a relatively weak effect on its richness. Redundancy analysis indicated that moisture had a greater impact on the structure of soil bacterial communities; while straw addition had a greater impact on the structure of soil fungal communities. At the phylum level, soil bacteria and fungi were not affected by moisture and straw addition. The dominant bacteria in the soil bacterial communities of each treatment were Proteobacteria and Acidobacteria (relative abundance > 15.0%); the dominant fungi in the soil fungal communities were Ascomycota and Basidiobolomycota (relative abundance > 5.0%). Therefore, soil moisture and straw addition have significant effects on the composition and structure of soil phosphorus cycling microbial communities in paddy fields.
