QTLseq of Gummy Stem Blight resistant and susceptible bulks from Sugar Baby x PI 189225

Gummy stem blight (GSB) is an important fungal disease affecting cucurbit crops worldwide. GSB resistance have been identified in several watermelon accessions and introgression of resistance could be accelerated using marker assisted selection. The goal of this study is to identify QTL associated with GSB resistance in watermelon. QTLseq of Gummy Stem Blight resistant and susceptible bulks from Sugar Baby x PI 189225. Leaf materials were collected from F2 plants. F2:3 seed lots were screened for resistance to gummy stem blight using Stagonosporopsis citrulli isolate 12178A in a greenhouse at the two true leaf stage. Resistance ratings from the F2:3 plants were used to approximate the resistance of individual F2 plants and the 12 most resistant and susceptible lines had their DNA extracted and where used to form bulks of resistant and susceptible DNA.