Abstract

Ipomoea batatas (L) Lam.'s sweet potato is a common food crop, particularly in developing nations. The crop's primary breeding objective has been to increase dry matter content and storage root yield, which necessitates DNA marker-assisted breeding. Using 601 simple-sequence repeat (SSR) primer pairs, we constructed a high-density genetic linkage map of sweet potato using a mapping population of 500 F1 individuals from a cross between Xushu 18 (female) and Xu 781 (male). The Xushu 18 map had 90 linkage groups with 5547 SSR markers and covered 18,263.5 cM, while the Xu 781 map had 90 linkage groups with 4599 SSR markers and covered 18,043.7 cM. These maps have the highest genome coverage of any sweet potato genome that has been reported so far. Storage-root yield was explained by 33 QTL, while dry matter content was explained by 16 QTL, accounting for 6.5%–47.5% of variation. The foundation for marker-assisted breeding and the fine mapping and cloning of QTL in sweet potatoes is provided by these findings.