Molecular markers linked to the resistance to race 3 of the soybean cyst nematode Heterodera glycines
Valdemar de Paula Carvalho; Ricardo Vilela Abdelnoor; Álvaro Manuel Rodrigues Almeida; Carlos Alberto Arrabal Arias and Romeu Afonso de Souza Kiihl
The objective of this study was to identify molecular markers associated with the resistance to race 3 of the SCN. Two microsatellites (Satt187 and Satt309) and three RAPD markers (OPAG-05946, OPF-041038, and OPAQ-011987) were found which explained 31.3%, 28.9%, 13.8%, 11.4% and 9.9%, respectively, of the phenotypic resistance variation to race 3 of the SCN. However, by multiple regression analysis, with the elimination of markers which least contributed to an explanation of the resistance, the most significant combination occurred with the inclusion of the markers Satt187 and Satt309, which together explained 75.2% of the resistance. These markers were mapped in two distinct regions. One located in the linkage group G with the markers OPAG-05846, OPF-041038, OPAQ-011987 and Satt309 at an interval of 34.7 cM, and another located in the group A2 with the marker Satt187. Inheritance studies have shown those two dominant genes control resistance to SCN, in the population analyzed.