The filamentous fungi genus Fusarium contains many plant pathogens. Wheat can restrict the invasion of many non-adapted Fusarium spp., including Fusarium oxysporum f. sp. cubense (Foc), which is a critical threat to global banana production, but is susceptible to Fusarium graminearum, which is the primary causal agent of Fusarium head blight. Wheat responses to both adapted (susceptible) and non-adapted (nonhost resistant) fungal pathogens haven’t been resolved at the single-cell level. The Tang lab previously identified infection stage-resolved molecular strategies of F. graminearum invasion into wheat seedling coleoptiles using laser microdissection-facilitated fungal profiling. How wheat cell transcriptomic states change over time in response to F. graminearum has not been investigated.

The work published (August 22, 2025) in Developmental Cell reports single-cell RNA-seq profiling wheat seedling coleoptiles in response to the adapted F. graminearum and non-adapted Foc over three days, and discovery of compartmentalized immune responses to non-adapted Foc, contrasted with widespread immune activation in response to the virulent F. graminearum.

The authors profiled single-cell transcriptomes of wheat seedling coleoptiles in response to F. graminearum and the non-adapted Foc at 0-, 1-, 2-, and 3-days post inoculation. This work illustrates cell-type-specific responses of eight major cell types and shows that phloem and outer sheath cells are the most rapidly and drastically responsive cell types. The results show that the upregulation of immune responses engages multiple cell types. Single-cell expression patterns and microscopic analysis illustrate the compartmentalization of the nonhost resistance. The results suggest that the adapted pathogen F. graminearum attenuates immune responses at early stages and boosts profound defense responses at later stages. Trajectory analysis within a continuum of parenchyma and outer sheath cells indicates a gradual transition of parenchyma cells to divergent immune-activated states after exposure to different fungal pathogens. The chlorenchyma cells change into a state of low transcriptional activity in the early stage of F. graminearum infection. 

This work also offers a resource for identifying candidate genes in targeted cell types to develop F. graminearum-resistant wheat.

The study was conducted by Wanqian Wei, Shuang Li, Dong Zhang, and Weihua Tang. Biological Breeding-National Science and Technology Major Projects, the Natural Science Foundation of China, and the Strategic Priority Research Program of the Chinese Academy of Sciences supported this study.

Link: https://www.cell.com/developmental-cell/fulltext/S1534-5807(25)00498-8

Contact: Dr. Weihua Tang, Professor, Principal Investigator

               CAS Center for Excellence in Molecular Plant Sciences          

               Email: http://whtang@cemps.ac.cn

Single-cell profiling of wheat seedling coleoptile (A) responses to F. graminearum and the non-adapted Foc at 0-, 1-, 2-, and 3-days post inoculation (B) identifies eight major cell types (C) and parenchyma-outer sheath transition divergence (D).