| The objectives of this research were to: (1) determine the inheritance of soybean cyst nematode (SCN) resistance in a Glycine max ('S08-80') x G. soja (PI464925B) F2:5 Recombinant Inbred Line (RIL) population; and (2) identify quantitative trait loci (QTL) associated with SCN resistance. Transgressive segregation for resistance was observed, although neither parent was resistant to the Chatham and Ruthven SCN isolates. Root dry weight was a significant covariate influencing cyst counts. A female index (FI) identified one RIL that was resistant to the Chatham isolate (FI < 10). Seventeen and three RILs infected with Chatham and Ruthven isolates, respectively, had mean adjusted cyst counts of zero (p = 0.05). Unique QTLs, which derived resistance from G. soja, were identified on linkage groups I, K, and O, and individually explained up to 8% of the total phenotypic variation. The incorporation of these regions could increase the durability of SCN resistant cultivars. |
