Kumar Pawan, Nimbal Somveer, Budhlakoti Neeraj, Singh Varsha, Sangwan Rajvir Singh
Department of Genetics and Plant Breeding, CCS Haryana Agricultural University, Hisar, 125004, India.
ICAR-Indian Agricultural Statistics Research Institute, New Delhi, 110012, India.
J Appl Genet. 2022 Feb;63(1):87-101. doi: 10.1007/s13353-021-00667-8. Epub 2021 Oct 31.
A total of 96 different genotypes of upland cotton (Gossypium hirsutum) were selected from the breeding material and germplasm available at CCS HAU, India, to find the novel marker-trait associations for morphological traits used for registration of variety in upland cotton. Twenty-three morphological traits of the selected genotypes were recorded in field trials conducted in two replication of randomized block design during Kharif 2018 and 2019. A total of 11 traits showed sufficient variations in the screened germplasm and the same were further used for association mapping. A total of 168 SSRs were used for genotyping, of which 97 SSRs showed polymorphism amplifying 293 different alleles with an average of 3.02 alleles per SSR. Clustering, principal component analysis, and population structure analysis advocated that the current germplasm panel has enough diversity to be considered for association mapping. A total of 20 significant marker-trait associations were identified by the mixed linear model (MLM) and compressed mixed linear model (CMLM), of which 15 were common to both models, hence considered as promising associations. To the best of our knowledge, it is a first attempt to identify the linked markers in relation to morphological traits for the cotton crop. Results of the present study will be highly useful in speeding up variety registration programmes of upland cotton complementing to Distinctiveness, Uniformity, and Stability (DUS) testing.
从印度CCS HAU现有的育种材料和种质资源中选取了96种不同基因型的陆地棉（Gossypium hirsutum），以寻找与陆地棉品种登记所用形态性状相关的新型标记-性状关联。在2018年和2019年雨季进行的随机区组设计的两次重复田间试验中，记录了所选基因型的23个形态性状。共有11个性状在筛选出的种质资源中表现出足够的变异性，并进一步用于关联作图。总共使用168个SSR进行基因分型，其中97个SSR表现出多态性，扩增出293个不同的等位基因，每个SSR平均有3.02个等位基因。聚类分析、主成分分析和群体结构分析表明，当前的种质资源库具有足够的多样性，可用于关联作图。通过混合线性模型（MLM）和压缩混合线性模型（CMLM）共鉴定出20个显著的标记-性状关联，其中15个在两个模型中都相同，因此被认为是有前景的关联。据我们所知，这是首次针对棉花作物的形态性状鉴定连锁标记。本研究结果将对加速陆地棉品种登记计划、补充特异性、一致性和稳定性（DUS）测试非常有用。
