RESEARCH ARTICLE Identification of Associated SSR Markers for Yield Component and Fiber Quality Traits Based on Frame Map and Upland Cotton Collections

Detecting QTLs (quantitative trait loci) that enhance cotton yield and fiber quality traits and accelerate breeding has been the focus of many cotton breeders. In the present study, 359 SSR (simple sequence repeat) markers were used for the association mapping of 241 Up-land cotton collections. A total of 333 markers, representing 733 polymorphic loci, were de-tected. The average linkage disequilibrium (LD) decay distances were 8.58 cM (r2> 0.1) and 5.76 cM (r2> 0.2). 241 collections were arranged into two subgroups using STRUC-TURE software. Mixed linear modeling (MLM) methods (with population structure (Q) and relative kinship matrix (K)) were applied to analyze four phenotypic datasets obtained from four environments (two different locations and two years). Forty-six markers associated wit