Detection of the quantitative trait loci for α-amylase activity on a high-density genetic map of rye and comparison of their localization to loci controlling preharvest sprouting and earliness

The objectives of the research were to determine the position of quantitative trait loci (QTL) for alpha-amylase activity on the genetic map of a rye recombinant inbred line population-S120 x S76-and to compare them to known QTL for preharvest sprouting and heading earliness. Fourteen QTL for alpha-amylase activity on all seven chromosomes were identified. The detected QTL were responsible for 6.09-23.32% of alpha-amylase activity variation. The lowest LOD value (2.22) was achieved by locus QAa4R-M3 and the highest (7.79) by locus QAa7R-M1. Some QTL intervals for features of interest overlapped partially or completely. There were six overlapping QTL for alpha-amylase activity and preharvest sprouting (on 1R, 3R, 4R, 6R, 7R) and the same number for preharvest sprouting and heading earliness (on 1R, 2R, 6R, 7R). Furthermore, there was one interval partially common to all three traits, mapped on the long arm of chromosome 1R. Testing of lines originating from hybrid breeding programs, such as S120 and S76, may provide important information about the most significant genes and markers for selection in commercial breeding. Among the statistically significant markers selected in the Kruskal-Wallis test (P < 0.005), there were 55 common ones for preharvest sprouting and heading earliness (1R, 2R, 6R), 30 markers coinciding between alpha-amylase activity and preharvest sprouting (5R, 7R) and one marker for alpha-amylase activity and heading earliness (6R).