Identification and Evaluation of Quantitative Trait Loci (QTL) Associated with Soybean Cyst Nematode HG Type 2.5.7

Abstract

Soybean cyst nematode (SCN) is one of the most damaging pests of soybean (Glycine max) worldwide. Currently, more than 95% of SCN-resistant cultivars grown in North America carry the resistance genes from PI88788, which are not resistant to all the Heterodera glycines(HG) types, including HG Type 2.5.7. The objectives of this study were to detect molecular markers associated with the SCN HG Type 2.5.7 and study the relationship between yield and the new resistance genes in two F4-derived recombinant inbred line (RIL) populations derived from crosses between susceptible cultivars OAC Brooke and OAC Calypso and the resistant source, LD07-3419. In total, five quantitative trait loci (QTL) were identified associated with the SCN resistance that explained up to 17% of the phenotypic variation in the populations. In this study, no significant correlation was found between seed yield and the SCN resistance or the detected QTL.