Genetic Analysis of Fusarium Wilt Resistance in Upland Cotton Germplasm (Gossypium hirsutum L.)

Abstract The causative agent of fusarium wilt (FW) disease, Fusarium oxysporum f. sp. vasinfectum (FOV) pathogen, is one of the economically serious soil fungi that cause significant damage to cotton crops worldwide. For several years, this pathogen has been detrimentally affecting cotton production in many countries including Uzbekistan and the United States. The damage is often resulted from drying up and the death of cotton seedlings. In this study, we evaluated the resistance of cotton (Gossypium hirsutum L.) lines, obtained from the Uzbekistan cotton germplasm collection, against FOV race 4 by infecting them with the pathogen four times during two years in a phytotron condition. Several cotton lines showed high resistance to FW diseases, such as Rex, PD-648, Mebane B-1, Las Brenas-347, and DPZ-554085. The screening was conducted with a total of 118 simple sequence repeat (SSR) markers known to be associated with FW resistance to determine the genetic polymorphisms between resistant and susceptible cotton accessions. A total of 40 markers were polymorphic and produced 165 alleles, with an average of 4.125 alleles per locus. The FW-resistant cotton lines with resistance marker alleles would be useful sources for marker-assisted selection (MAS) approaches to developing wilt-resistant cotton cultivars with superior fiber yield and quality.