Linkage disequilibrium mapping of morphological, resistance, and other agronomically relevant traits in modern spring barley cultivars

摘要

A set of 148 modern spring barley cultivars was explored for the extent of linkage disequilibrium (LD) between genes governing traits and nearby marker alleles. Associations of agronomically relevant traits (days to heading, plant height), resistancetraits (leaf rust, barley yellow dwarf virus (BYD)), and morphological traits (rachilla hair length, lodicule size) with AFLP markers and SSR markers were found. Known major genes and QTLs were confirmed, but also new putative QTLs were found. The LD mapping clearly indicated the common occurrence of Rph3, a gene for hypersensitivity resistance against Puccinia hordei, and also confirmed the QTL Rphq2 for prolonging latency period of P. hordei in seedlings. We also found strong indication for a hitherto not reported gene for resistance or tolerance to BYD on chromosome 2, linked to SSR marker HVM054. Our conclusion is that LD mapping is a valuable additional tool in the search for applicable marker associations with major genes and QTLs.