Is within-field spatial variation in wheat Fusarium crown rot associated with rhizosphere microbiome and soil nutrients

Abstract

Fusarium crown rot (FCR) of wheat, caused predominantly by Fusarium pseudograminearum, frequently exhibits marked spatial heterogeneity within individual fields despite uniform cultivars and agronomic management. However, the mechanisms underlying this within-field variation remain poorly understood. In this study, we investigated six commercial wheat fields in Henan Province, China, each containing distinct highly diseased (HD) and lightly diseased (LD) zones. Soil physicochemical properties and rhizosphere microbial communities (characterised via 16S rRNA and ITS amplicon sequencing) were compared between HD and LD zones. Despite identical management histories, HD and LD zones differed significantly in soil pH, nitrate nitrogen, available potassium, and magnesium. Furthermore, fungal communities in HD zones exhibited significantly lower α-diversity and distinct compositions, whereas bacterial communities showed only minor variations. Fusarium was significantly enriched in HD zones, while putatively beneficial taxa, including Acremonium and Pseudoxanthomonas, were more abundant in LD zones. These findings provide new insights into the micro-ecological factors associated with within-field disease heterogeneity and support the development of site-specific management strategies for FCR.