Gene mapping and identification of candidate genes associated with fomesafen herbicide tolerance in Mung bean (Vigna radiata L.)

Huiying Shi, Changyou Liu, Shen Wang, Yan Wang, Zhixiao Zhang, Yingchao Shen, Sivakumar Paramasivam, Jing Tian & Baojie Fan

Theoretical and Applied Genetics; 28 February 2026; vol. 139; article 139

Key message

Through an integrated approach of genetic mapping, transcriptomics, and functional validation, we identified VrGSTU18 as the primary gene associated with fomesafen resistance in mung bean, providing a genetic resource for breeding herbicide-resistant varieties.

Abstract

Herbicides are widely applied for weed control in mung bean cultivation, and the development of new varieties with herbicide resistance is critical for weed management. In this study, a recombinant inbred line (RIL) population, derived from a cross between the fomesafen-resistant variety LZ177 and susceptible variety LD235, was used to map the genes related to fomesafen herbicide resistance. Genetic segregation analysis indicated that fomesafen resistance is controlled by a single dominant gene, following a 3:1 ratio. Genetic mapping combined BSA-seq revealed a candidate region of 1.17 Mb on chromosome 11. RNA-seq analysis of residual heterozygous line 198—comparing resistant (RHL198-R) and susceptible (RHL198-S) bulks at 0, 12, 24, 48, and 72 h after fomesafen treatment—identified 14,402 herbicide-responsive genes. Weighted gene coexpression network analysis (WGCNA) further identified nine modules highly correlated with fomesafen resistance, of which 13 potential candidate genes were selected within the 1.17 Mb interval. Among these, one-base (A) insertion/deletion in the exon of jg37117, which encode a tau-class glutathione S-transferase U18 (GSTU18), emerged as the most promising candidate gene. Heterologous expression of VrGSTU18 cloned from LZ177 in Arabidopsis conferred enhanced fomesafen resistance in T₁ transgenic seedlings compared to wild-type plants. These findings identified VrGSTU18 as a key candidate gene responsible for fomesafen resistance and provided a theoretical basis for molecular breeding in mung bean.

See https://link.springer.com/article/10.1007/s00122-026-05184-y