The use of Cicer reticulatum L. for genetic improvement of cultivated chickpea
Date
2020-05-26
Authors
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Journal ISSN
Volume Title
Publisher
ORCID
Type
Thesis
Degree Level
Masters
Abstract
The diverse gene pool of wild chickpea (Cicer reticulatum L.) has the potential for use to improve a range of agronomically important traits in cultivated chickpea. This study was conducted to evaluate the phenotypic and genetic variations of 486 lines derived from interspecific crosses between C. arietinum (CDC Leader) and 20 accessions of C. reticulatum. Field evaluations were done on the progeny at the F4 and F5 generations. The lines were grown at four locations in Saskatchewan over two consecutive years, 2017 (Saskatoon and Moose Jaw) and 2018 (Limerick and Lucky Lake). Significant variability was observed for different traits such as seed weight per plant, thousand seed weight, number of seeds per plant, and biomass. Correlation analysis showed significant positive correlation of seed yield with the yield components including seed weight per plant (r = 0.99), number of seeds per plant (r = 0.95), and biomass (r = 0.82), while negative correlation was obtained between thousand seed weight and number of seeds per plant (r = -0.16). The significant positive direct effects of the number of seeds per plant, thousand seed weight, and biomass on the seed weight was confirmed by path coefficient analysis. Cluster analysis based on the phenotypic data generated six clusters for potential identification of heterotic groups of the interspecific lines. Cluster I consisted of 67 lines potential for improvement of yield traits, while the lines in cluster VI showed improved resistance to ascochyta blight disease. Genotyping of the 381 interspecific lines and 20 parents using tGBS identified 14,591 SNPs ranging from 634 to 2244 per chromosome. Neighbour-joining cluster analysis based on the SNP data grouped the 401 germplasms into 20 clusters. Admixture analysis revealed 9 groups that had a substantial amount of intermixing. The marker-trait association analysis using the mixed linear model (MLM) identified 51 SNPs that had significant associations with different traits. The SNPs on chr 4 were significantly associated with early flowering which were derived from the wild parents. Highest number of SNPs (13) were found to be associated with each of the trait such as thousand seed weight (g), and seed weight per plant (g).
Description
Keywords
Chickpea, Cicer reticulatum, C. arietinum, SNP marker, Diversity, Improvement
Citation
Degree
Master of Science (M.Sc.)
Department
Plant Sciences
Program
Plant Sciences