Segregating BCFinterspecific hybrids betweenandreveal a major effect locus for blackleg resistance on chromosome B2
Source: PubMed Central Open Access, NCBI / U.S. National Library of Medicine
Blackleg (Phoma,) is one of the most important diseases affecting rapeseed (, 2n = AACC) worldwide. Although a number of major blackleg resistance genes have been identified in, finding novel sources of resistance is critical in dealing with this rapidly evolving fungal pathogen. Black mustard (, 2n = BB) is a highly resistant wild relative species for which at least one blackleg resistance gene has been described (on chromosome B4), but which has been rarely investigated as a source of blackleg resistance for introgression breeding (probably because it is self-incompatible, heterozygous, difficult to hybridize withand until recently lacked the genetic and genomic resources available for theA- and C-genome species). We produced allohexaploid hybrids (2n = AABBCC) betweenandfollowed by two generations of backcrossing to develop a BCFpopulation segregating for inheritance of specific B-genome chromosomes from. This population was phenotyped for blackleg resistance using a cotyledon test with blackleg isolate “JN2” (,,,,,,) and genotyped with B-genome chromosome-specific markers. Resistance segregated with the presence of chromosome B2 (< 0.0001). Future work will target the identification or production of introgression lines, and recovery of this genetic locus from the B genome in a rapeseed (2n = AACC) genomic background. Our work highlights the potential ofandwild relatives as sources of novel biotic stress resistances. Supplementary Information The online version contains su
Abstract
Blackleg (Phoma,) is one of the most important diseases affecting rapeseed (, 2n = AACC) worldwide. Although a number of major blackleg resistance genes have been identified in, finding novel sources of resistance is critical in dealing with this rapidly evolving fungal pathogen. Black mustard (, 2n = BB) is a highly resistant wild relative species for which at least one blackleg resistance gene has been described (on chromosome B4), but which has been rarely investigated as a source of blackleg resistance for introgression breeding (probably because it is self-incompatible, heterozygous, difficult to hybridize withand until recently lacked the genetic and genomic resources available for theA- and C-genome species). We produced allohexaploid hybrids (2n = AABBCC) betweenandfollowed by two generations of backcrossing to develop a BCFpopulation segregating for inheritance of specific B-genome chromosomes from. This population was phenotyped for blackleg resistance using a cotyledon test with blackleg isolate “JN2” (,,,,,,) and genotyped with B-genome chromosome-specific markers. Resistance segregated with the presence of chromosome B2 (< 0.0001). Future work will target the identification or production of introgression lines, and recovery of this genetic locus from the B genome in a rapeseed (2n = AACC) genomic background. Our work highlights the potential ofandwild relatives as sources of novel biotic stress resistances. Supplementary Information The online version contains supplementary material available at 10.1007/s11032-026-01690-5. Abs1