Long-term continuously monocropped peanut significantly changed the abundance and composition of soil bacterial communities

Abstract

Soil sickness is the progressive loss of soil quality due to continuous monocropping. The bacterial populations are critical to sustaining agroecosystems, but their responses to long-term peanut monocropping have not been determined. In this study, based on a previously constructed gradient of continuous monocropped plots, we tracked the detailed feedback responses of soil bacteria to short- and long-term continuous monocropping of four different peanut varieties using high-throughput sequencing techniques. The analyses showed that soil samples from 1- and 2-year monocropped plots were grouped into one class, and samples from the 11- and 12-year plots were grouped into another. Long-term consecutive monocropping could lead to a general loss in bacterial diversity and remarkable changes in bacterial abundance and composition. At the genera level, the dominant genus Bacillus changed in average abundance from 1.49% in short-term monocropping libraries to 2.96% in the long-term libraries. The dominant species Bacillus aryabhattai and Bacillus funiculus and the relatively abundant species Bacillus luciferensis and Bacillus decolorationis all showed increased abundance with long-term monocropping. Additionally, several other taxa at the genus and species level also presented increased abundance with long-term peanut monocropping; however, several taxa showed decreased abundance. Comparing analyses of predicted bacterial community functions showed significant changes at different KEGG pathway levels with long-term peanut monocropping. Combined with our previous study, this study indicated that bacterial communities were obviously influenced by the monocropping period, but less influenced by peanut variety and growth stage. Some bacterial taxa with increased abundance have functions of promoting plant growth or degrading potential soil allelochemicals, and should be closely related with soil remediation and may have potential application to relieve peanut soil sickness. A decrease in diversity and abundance of bacterial communities, especially beneficial communities, and simplification of bacterial community function with long-term peanut monocropping could be the main cause of peanut soil sickness.

Soil Metagenomics Reveals Effects of Continuous Sugarcane Cropping on the Structure and Functional Pathway of Rhizospheric Microbial Community

“…Fungi play a key role in decomposition, and the composition of soil fungi community is affected by management and soil nutrient status ( Sui et al, 2019 ). Among the fungi identified in our study, the diversity of fungal communities increased from NCC to CC30 and a similar result was also reported in continuous cropping of vanilla and peanut ( Xiong et al, 2015b ; Chen et al, 2020 ). The dominant phyla of fungi in continuous cropping of sugarcane were Ascomycota, Basidiomycota, and Chytridiomycota, which was consistent with previous studies in continuous cropping of sweet potato and Panax notoginseng ( Tan Y. et al, 2017 ; Gao et al, 2019 ).…”

“…However, continuous cropping obstacles are caused by complex factors, and the mechanisms remain unclear. Recently, an increasing number of studies have begun to focus on the roles of soil microbial communities in continuous cropping practices ( Xiong et al, 2015b ; Gao et al, 2019 ; Chen et al, 2020 ). Sugarcane, one of the important tropical crops in China, has been planted in monoculture in coastal areas of southern China due to the limited arable land area, which has resulted in soil sickness and significant losses to crop yields could be caused by changes in the microbial composition and soil characteristics ( Miura et al, 2016 ; Kelly et al, 2018 ).…”

“…Microbial community composition and diversity are associated with soil quality and plant health ( Berendsen et al, 2012 ). A large number of studies have shown that there are significant differences in the microbial biomass and composition of bacterial and fungal communities at different stages of monoculture ( Gao et al, 2019 ; Alami et al, 2020 ; Chen et al, 2020 ). Interestingly, the diversity of bacterial communities increased from NCC to CC10, and then decreased from CC10 to CC30 in this study.…”

Distinct Root Microbial Communities in Nature Farming Rice Harbor Bacterial Strains With Plant Growth-Promoting Traits

“…It has been reported that the relative abundances of Curvibacter and Anaeromyxobacter were greater in unfertilized soils than in fertilized soils (Kumar et al, 2018;Hui et al, 2019). Chen et al (2020) also reported that the relative abundance of the Piscinibacter decreased over a long-term monocropping practice of peanut crops. Our results demonstrated the enrichment of the beneficial bacterial community with unfertilized nature farming.…”

Continuous monocropping highly affect the composition and diversity of microbial communities in peanut (Arachis hypogaea L.)

“…It is a rich source of protein, vitamins, minerals and medicinally active components, such as flavonoids and phenolic compounds (Sui et al, 2018). According to the National Bureau of Statistics of China, peanut crop is being grown on area 4,608 khm2 during 2017 planting season (The National Bureau of Statistics of China, 2018) (Chen et al, 2020). Due to limited arable land and increasing pressure of regional agro-industrialization, large scale peanut monocropping is a common practice in China.…”