Genetic diversity of Turkish commercial cotton varieties revealed by molecular markers and fber quality traits

Abstract

To assess the genetic diversity and relationships among commercial Gossypium species released in Turkey between 1964 and2014, 96 cotton varieties were analyzed using morphological and molecular markers. Morphological analysis was performed basedon 4 fber quality traits including fber length, strength, fneness, and uniformity, and the mean values of each trait for each genotypewere calculated using 2-year data. Te results showed that most of the genotypes have long fber length, very high fber strength, coarse(45 genotypes) or average (50 genotypes) fber fneness, and high uniformity. Twenty-six simple sequence repeat (SSR) markers and14 markers linked to quantitative trait loci (QTLs) for fber quality traits produced a total of 103 alleles, with an average of 2.57 allelesper locus ranging from 80 bp to 300 bp products, with an average polymorphism information content (PIC) value of 0.233. MarkersDPL513 and DPL431 (among 26 SSR markers) and markers CIR246 and BNL4108 (among 14 molecular markers) were found to bevery informative, with 0.724, 0.663, 0.749, and 0.583 PIC values, respectively. Te combined morphological and molecular data analysisresulted in more than 8 clades using the unweighted pair group method with arithmetic average (UPGMA). Te upland cotton varietieswere distinctly separated from the lowland cotton variety Maydos Yerlisi (Gossypium herbaceum L.). Within the upland cotton varieties,the Egyptian cotton variety Giza 70 (G. barbadense L.) was distinctly separated from commercial cotton varieties of Turkey ( G. hirsutumL.), as revealed by both morphological and molecular dendrograms. Principal component analysis (PCA) derived from combined datawas in agreement with UPGMA analysis. It is concluded that commercial Turkish cotton varieties have a good genetic diversity withhigh fber quality, considering the upland cotton s narrow genetic structure. Tese results can provide a useful guide for selecting specifcgermplasm with distinct genetic backgrounds in cotton breeding programs.