Functional diversity of rhizosphere soil microbial communities in response to different tillage and crop residue retention in a double-cropping rice field

Abstract

Microbial community functional diversity is a sensitive indicator of soil quality, soil management such as tillage and crop residue which can affect the microbial community functional diversity of paddy field. However, there is still limited information about the influence of different tillage and crop residue management on rhizosphere soil microbial community functional diversity in a double-cropping rice (Oryza sativa L.) field. Therefore, four tillage treatments were set up in paddy field, tillage treatments were included: conventional tillage with residue incorporation (CT), rotary tillage with residue incorporation (RT), no-tillage with residue retention (NT), and rotary tillage with residue removed as control (RTO). And the effects of CT, RT, NT, and RTO treatments on the average well color development (AWCD), genetic diversity indices and carbon source utilization of rhizosphere soil were studied in the present paper. The results showed that the values of AWCD with CT, RT and NT treatments were higher than that of RTO treatment. It was implied that application of crop residue management resulted in the variation of the carbon utilization efficiency of rhizosphere soil microbial communities. At maturity stages of early and late rice, the Richness indices, Shannon indices and McIntosh indices with CT treatment were significantly higher than that of RTO treatment, and with the order as CT>RT>NT>RTO. Principal component analysis (PCA) results indicated that there were significant differences in carbon substrate utilization patterns among different tillage treatments. Carbohydrates and amino acids were the main carbon resources utilized by rhizosphere soil microbes. Therefore, the combined application of tillage with crop residue management could significantly increase the rhizosphere soil microbial community functional diversity in the double-cropping paddy field of southern China.

Impact of rice straw management strategies on rice rhizosphere microbiomes

“…Aside from burning, there are emerging efforts to incorporate RS into the soil or use it as a mulch (Yuan et al, 2014). Clearly, such incorporation and mulching practices can exert effects on the subsequent crop, for instance wheat (Rahman et al, 2005) and Chinese milk vetch (Astragalus sinicus L.), by virtue of modulations of soil microbial activity and diversity (Tang et al, 2020). Moreover, the treatments require mechanization and often water and additional fertilizer are added to enhance decomposition processes (Kalkhajeh et al, 2021).…”

“…Its incorporation into soil increases organic carbon and nitrogen concentrations and modulates the quality and quantity of the soil organic matter (SOM) by increasing the labile, particulate and dissolved organic carbon, and improving physicochemical soil properties, having a crucial influence on the soil microbial biomass and microbial soil activity (Luo et al, 2016;Tang et al, 2020;Yan et al, 2020). Thus, returning rice straw to soil may contribute with 31-42 kg N ha − 1 , 8 kg P ha − 1 , 34-61 kg K ha − 1 and 2.1-2.2 ton C h − 1 per crop cycle (Hung et al, 2019).…”

Vinasse and straw retention decrease fungal diversity and pathogenicity in sugarcane soil / Aplicação de vinhaça e retenção de palha diminuem a diversidade e patogenicidade de fungos em solo canavieiro

“…The soil microbial diversity has a positive correlation with the productivity and sustainability of a system (van der Heijden et al, 2008), and loss and simplification of soil community composition impair multiple ecosystem functions, including plant diversity, decomposition, nutrient retention, and nutrient cycling (Wagg et al, 2014). Soil microbial diversity, richness and evenness are sensitive to changes in land management practices, such as cropping systems, tillage and fertilization (Hartmann et al, 2015;Tang et al, 2020).…”