Alternate drip irrigation regulates the soil fungal community structure and metabolic function based on root–fungus interactions. (5th January 2023) - Wang, Jingwei
Abstract: Fungal communities play an essential role in soil nutrient cycling, but the mechanism of their response to soil dry–wet cycles under alternate drip irrigation (ADI) is uncertain, which limits the improvements in crop yield that can be achieved through fungal community management in controlled environmental agriculture. In this study, surface drip irrigation was used as the control (CK) to study the effects of ADI with different thresholds of irrigation (designated A50, A60, and A70) on the soil fungal community and root–fungus interactions and to analyze the contribution of root–fungus interactions to tomato yield. Compared with CK, ADI increased the tomato fine root length and specific root fork number but decreased fungal community richness while shaping fungal communities with different compositions and functional metabolisms. For example, the relative abundance of Basidiomycota in A70 was 8.73, 3.25, and 2.81 times those of CK, A50, and A60 respectively. Among the well‐defined fungal functional guilds, the fungal community of A50 was dominated by pathotroph‐saprotroph‐symbiotroph; however, that of A60 was dominated by pathotroph‐saprotroph‐symbiotroph and pathotroph‐symbiotroph, and that of A70 was dominated by pathotroph‐symbiotroph. The root–fungus interaction model showed significant one‐way direct positive effects between adjacent pairs of variables among the four variables (from tomato specific root fork number and fine root length to Basidiomycota, total nitrogen in roots and then tomato yield). These results provide insights into the possibility of regulating the fungal community by optimizing drip irrigation techniques to improve water use efficiency and tomato yield.