Abstract
Ascochyta blight caused by Ascochyta rabiei is one of the most important foliar diseases of chickpea that can lead to significant yield losses worldwide. A genome-wide association study (GWAS) was applied on a panel of 165 chickpea genotypes against A. rabiei isolates belonging to six different pathotypes. Large phenotypic variation in disease reaction was observed, as the frequency of resistance to pathotypes-I and III was comparatively higher than resistance to other pathotypes. Overall, among the all genotype × pathotype interactions, 259 resistance responses were identified and genotypes were grouped into four clusters based on their phenotypic reactions. The chickpea panel genotyped using DArTseq assay was used for genome-wide association mapping (GWAS). The GWAS revealed 30 marker-trait associations (MTAs) representing 17 quantitate trait loci (QTL) across all chickpea chromosomes. Among them, 11 R-QTLs were associated with resistance to specific pathotype, and 6 R-QTLs were associated with resistance to two or more pathotypes. Most of these R-QTLs overlapped with the previously reported R-QTLs for resistance to A. rabiei, whereas identified R-QTLs on chromosomes Ca1, Ca2, Ca6 and Ca7 are most likely novel. Meanwhile, annotation within the R-QTL intervals revealed genes involved in salicylic acid (SA) and jasmonic acid (JA) regulation pathways as well as cell death programming. The known and novel R-QTL identified in this study may be targeted for use in future chickpea breeding programs to recombine different loci to improve the durability of resistance to multiple A. rabiei isolates/pathotypes.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
