A novel QTL conferring Fusarium crown rot resistance on chromosome 2A in a wheat EMS mutant

https://link.springer.com/article/10.1007/s00122-024-04557-5

Theoretical and Applied Genetics,Volume 137, article number49, (2024)

Xiangru Xu,Yuqing Su,Jiatian Yang,Jinlong Li,Yutian Gao,Cong Li,Xingyi Wang,Lulu Gou,Zhi Zheng,Chaojie Xie,Jian Ma&Jun Ma

Abstract

Fusarium crown rot (FCR) is a fungal disease that causes significant yield losses in many cereal growing regions in the world. In this study, genetic analysis was conducted for a wheat EMS mutant C549 which showed stable resistance to FCR at seedling stage. A total of 10 QTL were detected on chromosomes 1A, 2A, 3B, 4A, 6B, and 7B using a population of 138 F7recombinant inbred lines (RILs) derived from a cross between C549 and a Chinese germplasm 3642. A novel locus Qfcr.cau-2A, which accounted for up to 24.42% of the phenotypic variation with a LOD value of 12.78, was consistently detected across all six trials conducted. Furthermore, possible effects of heading date (HD) and plant height on FCR severity were also investigated in the mapping population. While plant height had no effects on FCR resistance, a weak and negative association between FCR resistance and HD was observed. A QTL for HD (Qhd.cau-2A.2) was coincident withQfcr.cau-2A. Conditional QTL mapping indicated that although Qfcr.cau-2A and Qhd.cau-2A.2had significant interactions,Qfcr.cau-2A remained significant after the effects of HD was removed. It is unlikely that genes underlying these two loci are same. Nevertheless, the stable expression of Qfcr.cau-2A in the validation population of 148 F7RILs developed between C549 and its wild parent Chuannong 16 demonstrated the potential value of this locus in FCR resistance breeding programs.

Key message

A novel QTL on chromosome 2A for Fusarium crown rot resistance was identified and validated in wheat.