• Effects of continuous cropping on fungal community structure succession in rhizosphere and non-rhizosphere soils of cassava

    Subjects: Biology >> Botany >> Applied botany submitted time 2024-05-15 Cooperative journals: 《广西植物》

    Abstract: For revealing the mechanism of cassava continuous cropping obstacle formation, the current study planted cassava in a fixed field for three consecutive years, and applied high-throughput sequencing technology and bioinformatics to explore effects of continuous cropping on fungal community structure of both rhizosphere and non-rhizosphere of cassava soils. The results were as follows: (1) Continuous cropping caused significant effects on the α diversity and β diversity of rhizosphere and non-rhizosphere soils of cassava. (2) The dominant fungi phyla of cassava rhizosphere and non-rhizosphere soils were Ascomycota, SAR_k__norank, Basidiomycota, Mucoromycota, and unclassified _k __Fungi, while the main classes were Sordariomycetes, Eurotiomycetes, Dothideomycetes and Intramacronucleata. The composition of Ascomycota of the non-rhizosphere soils varied with the continuous cropping years significantly. In the rhizosphere, Hypocreales, Chaetothyriales, Myrothecium, Dothideomycetes, and Sordariomycetes were observed in 2019 and 2020, while Monosiga was found in 2021. (3) Soil pH, organic matter content, available nitrogen content, available phosphorus content, available potassium content, and urease activity significantly influenced the structure of fungal communities, especially for distributions of Ascomycota, SAR_k__norank, Basidiomycota, and Mucoromycota. In conclusion, continuous cropping of cassava influenced soil physicochemical properties through the accumulation of root exudates, thus altering the survival environment of fungi, leading to differences of the diversity and the abundance of fungal communities between cassava rhizosphere and non-rhizosphere soils. The relative abundance of Hypocreales, Myrothecium, and Sordariomycetes decreased with continuous cropping years, which may be one of main causes of the continuous cropping obstacles of cassava.