Identification of QTLs Associated with Total Soyasaponin Content in Soybean (Glycine max (L.) Merr.)

Soyasaponins are valuable compounds in certain drugs, industry, food additives and surfactants. Selecting cultivars with higher-soyasaponin content along with agronomic traits is a main goal for many soybean breeders. The aim of the present study was to identify the quantitative trait loci (QTLs) associated with total soyasaponin content through a F-2 population, which was derived from a cross between Ha 91016 (higher soyasaponin content cultivar, 16.8 mg g(-1)) and N98-9445A (lower soyasaponin content, only 5.7 mg g(-1)). A genetic linkage map including a total of 162 simple sequence repeat markers was constructed, which covered the total length 2735.5 cM, and the average distance between markers was 16.96 cM. Two QTLs associated with total soyasaponin content were identified. One, qSAP_1 (located in sat_044-satt102 of linkage group (LG) K), could explain 12.6% of phenotypic variance. The other, qSAP_2, was located between satt368 and sat_413 of LG D1a, which could explain 15.8% of phenotypic variance. It was concluded that the two QTLs would have some potential value for marker-assisted selection for high-soyasaponin content breeding in soybeans.