highly significantP < 0.00001
In the SA27063 × A17 F 2 population a highly significant quantitative trait locus (QTL, LOD = 7.37; P < 0.00001) named r esistance to the n ecrotroph P homa m edicaginis one ( rnpm1 ) genetically mapped to the top arm of linkage group 4 (LG4). rnpm1 explained 33.6% of the phenotypic variance in the population's response to infection depicted on a 1–5 scale and was tightly linked to marker AW256637 .