Fine mapping of a novel QTL CsFSG1 for fruit skin gloss in cucumber ( Cucumis sativus L.)

Cucumber ( Cucumis sativus L.) is an important vegetable crop that is popular with many people. Peel gloss is a highly valued external quality trait that affects the market value of cucumbers, and it directly influences the purchasing psychology of consumers. Nonetheless, the candidate genes and underlying genetic mechanism for this important cucumber trait are not well understood. In this study, we successfully mapped a fruit skin gloss QTL interval to chromosome 3 (26.04–26.14 Mb) using BSA and GWAS methods. Among the eleven candidate genes in the interval, the cytochrome P450 family gene CsCYP86B1 was identified as the candidate for control of fruit skin gloss in cucumber. The expression of CsCYP86B1 in 0-day fruit skin was significantly lower in the low-gloss isogenic line NIL-1334 than in the high-gloss isogenic line NIL-1325. Our findings provide new insights for improving fruit skin gloss in cucumber breeding.