Preliminary Screening of Cotton Germplasm for Resistance to Target Spot and Areolate Mildew

252 accessions of G. hirsutum and G. barbadense were examined for resistance to Target spot (Corynespora cassiicola) and Areolate mildew (Remularia areola) under field conditions. These accessions included wild germplasm lines provided by the USDA-ARS, Florence, South Carolina, advanced breeding lines, commercial cultivars and twenty-four 2018 Regional Breeders’ Testing Network (RBTN) lines. All the entries were rated individually for both diseases on a scale of 1 to 5, where 1 indicates resistance to disease and 5 indicates complete defoliation. The accessions TX-85, TX-1008, and TX-2139 showed consistently high resistance to Target Spot amongst all replications while no RBTNs or commercial cultivars showed as high resistance to Target spot. Also, accessions TX-2, TX-85, TX-2139, and TX-2390 showed moderate resistance to the disease. For Areolate mildew, accessions TX-786, TX-2402, TX-1419, and GB-1049 showed high resistance while accessions TX-226, TX-2311, and TX-2335 show moderate resistance. All the above accessions, along with susceptible checks (Phytogen 499 WRF for Target spot) will be tested in greenhouse conditions to confirm resistant traits and identify new sources of resistance to Target spot and Areolate mildew.