钙肥、铁肥对长期连作花生土壤真菌群落结构的影响

Effect of Calcium and Iron Fertilizer on Fungal Community Structure in Long-Term Continuous Cropped Peanut Soil

连作障碍是目前制约我国花生产业可持续发展的突出问题。解析花生连作障碍的机制,可以为缓解或解除花生连作障碍提供理论基础与技术支持。为了探究钙肥与铁肥对花生连作土壤真菌群落分布的影响,通过采用高通量测序技术分析了土壤真菌群落结构。UPGMA分析表明,施钙肥和铁肥均能影响长期连作花生土壤的真菌群落结构,并且施加这两种元素肥料对长期连作土壤真菌群落结构的影响程度均要大于花生品种对其的影响。热图分析表明,与对照相比,钙肥与铁肥处理下花生连作土壤真菌群落结构在门和属水平上都存在显著差异。在门分类水平上,钙肥和铁肥处理的子囊菌门、毛霉门在两个花生品种种植土壤中丰度均显著提高,担子菌门则有所下降,壶菌门丰度在花育20号连作土壤中下降,在花育26号连作土壤中却显著提高,且钙肥的影响明显强于铁肥。在属分类水平上,钙肥、铁肥均能明显改变连作花生土壤中真菌群落结构组成,且钙肥能显著增加花生连作土壤中优势真菌的总体丰度,花育26号连作土壤中的增幅明显高于花育20号,而铁肥处理的花育26号连作土壤中的优势真菌相对丰度同样增加,在花育20号连作土壤中却略有降低。以上结果表明,钙、铁元素施用会影响连作花生土壤中的真菌群落结构,且施加钙肥或铁肥能显著增加花生连作土壤中优势真菌的总体丰度。本研究为进一步揭示不同花生品种连作耐性差异机制揭开了新视角。

The continuous cropping obstacle is a prominent problem that restricts the sustainable development of the peanut industry in China.The analysis of the mechanism of peanut continuous cropping obstacles can provide theoretical basis and technical support for overcoming and alleviating the obstacles of peanut continuous cropping.To explore the effects of calcium and iron fertilizer on the distribution of fungal community in continuous cropped peanut soil,the calcium and iron fertilizer treated soil was analyzed using high-throughput sequencing technology,UPGMA methods,and heatmap analysis.The UPGMA analysis showed that applying calcium fertilizer or iron fertilizer can affect the fungal community structure of peanut soil,and that the influence of the fungal community structure of long-term continuous cropped peanut soil was greater than that of peanut varieties.Heatmap analysis showed that the fungal community structure varied significantly across taxonomic levels in the calcium and iron fertilizer treated soils compared with the control soil.At the phylum level,the abundance of Ascomycota and Mucoromycota significantly increased in the soil of both peanut varieties,while Basidiomycota decreased.The abundance of Chytridomycota decreased in Huayu20-cropped soil,but increased in Huayu26-cropped soil.The influence of calcium fertilizer was significantly stronger than that of iron fertilizer.At the genus level,the analysis further showed that calcium and iron fertilizer can significantly change the fungal community structure in peanut soil.Calcium fertilizer can significantly increase the overall abundance of dominant fungi in peanut soil,and the increase was significantly higher in Huayu26-cropped soil than in Huayu20-cropped soil.The relative abundance of dominant fungal was also increased in Huayu26-cropped soil,while slightly reduced in Huayu20-cropped soil under iron fertilizer treatment.The results indicated that the content of calcium and iron in continuous cropped peanut soil can affect the fungal community structure,and the application of calcium and iron fertilizer can significantly increase the overall abundance of dominant fungi in peanut cropped soil.This study opened a new perspective for further research on the difference mechanism of different degrees of continuous cropping tolerance in different peanut varieties.