Fiber Quality-Color Associations in Gossypium Hirsutum L. Hybrids

FIBER QUALITY-COLOR ASSOCIATIONS IN GOSSYPIUM HIRSUTUM L. HYBRIDS Khalikova Malokhat Babamuradovna DSc, professor, Scientific Research Institute of Cotton Breeding, Seed Production and Agrotechnology, Tashkent region, Uzbekistan E-mail: khalikovamalokhat@gmail.com Orcid ID: 0000-0001-9620-6131 Rakhmonova Rukhsora Bakhriddinovna Associate professor, Navoi State University, Navoi region, Uzbekistan E-mail: rahmonovaruhsora299@gmail.com Orcid ID: 0009-0001-6075-2306 Matyakubova Elmira Umrbekovna PhD, senior researcher, Scientific Research Institute of Cotton Breeding, Seed Production and Agrotechnology, Tashkent region, Uzbekistan E-mail: matyakubovaelmira@mail.ru Orcid ID: 0000-0002-1505-6832 Nurmamatov Aktam PhD, senior researcher Sharipov Shukhrat Tulkinovich PhD, senior researcher, Scientific Research Institute of Cotton Breeding, Seed Production and Agrotechnology, Tashkent region, Uzbekistan E-mail: sh.sharipov1972@mail.ru Orcid ID: 0000-0001-5109-2345 https://doi.org/10.5281/zenodo.19465190 Abstract. The use of naturally colored cotton fiber, which eliminates the need for chemical dyes and reduces environmental pollution, is a requirement of modern sustainable textile production. However, fiber color is usually negatively correlated with fiber quality in cotton. The objective of this study was to determine the polymorphism of fiber quality and color traits in cotton varieties and F4 hybrid combinations using SSR markers. As a result, hybrid combinations with high fiber quality stability (107 and 135 bp) and improved coloration, associated with a pleiotropic locus on chromosome 7 (genome A), were identified. Markers BNL1604 and NAU1043 demonstrated high informativeness for genotype identification, making them promising tools for molecular tagging of breeding material and accelerated selection for fiber quality and color traits. The use of SSR markers BNL1604 and NAU1043 enabled the identification of allelic combinations associated with improved fiber properties. The F4 hybrids L-001 × 010444 and Bukhara-6 × 02408 are recommended for further breeding as donors of genes for high fiber quality. Marker-based identification confirmed the effectiveness of SSR technology for accelerating selection in cotton breeding programs. The results of this study have both scientific and practical significance for developing environmentally safe varieties of naturally colored cotton with improved fiber properties. Keywords: cotton, fiber color, fiber quality, SSR markers, primers, polymorphism, molecular breeding.