Two quantitative trait loci (QTL) that confer resistance to the soybean cyst nematode (SCN, Heterodera glycines Riggs and Niblack) isolate PA3 (HG Type 0, Race 3) were previously mapped in a population of F2-derived lines developed from a cross with the Glycine soja Sieb. and Zucc. plant introduction (PI) 468916. These two QTL represent new resistance genes as they reside in genetic locations that differ from where SCN-resistance QTL in soybean [Glycine max (L). Merr.] cultivars map. The objectives of this research were to confirm the G. soja SCN-resistance QTL in a domestic soybean background and to localize, or better define, the positions of these QTL. Additional molecular markers were identified within the regions containing the SCN-resistance QTL by using amplified fragment length polymorphism (AFLP) markers and bulked segregant analysis (BSA). Each QTL was localized by developing and testing several backcross populations that segregated for different genome regions where the resistance QTL map. The SCN-resistance QTL on LG E was localized to a 13.2-cM interval with an average marker distance of 0.6 cM. The SCN-resistance QTL on LG G was localized to an 18.5-cM interval with an average marker distance of 3.1 cM. The AFLP-BSA technique proved to be beneficial for adding molecular markers to the two regions from G. soja that confer resistance to SCN. These closely linked markers will assist in map-based cloning of the 6. soja PI 468916 SCN resistance genes which could potentially uncover genes involved in the soybean-SCN interaction and aid with their continued exploration.
ASJC Scopus subject areas
- Agronomy and Crop Science