Preharvest sprouting (PHS) can severely damage barley (Hordeum vulgare L.) malting quality and is of particular concern in locations with a high frequency of precipitation around harvest. Malting quality and PHS resistance are often negatively correlated, and the SD2 locus on chromosome 5H has been associated with both traits. Using three spring barley populations, PHS, seed dormancy, and germination rate were mapped over six time points to identify changes in genetic control of these traits during the after-ripening period. HvAlaAT1 at the SD1 locus was associated with long-term dormancy and reduced germination rate. Ninety lines were Sanger sequenced for HvGA20ox1, but variants were not associated with PHS or germination traits. The allelic state of HvMKK3 was strongly associated with genetic PHS susceptibility in North American spring two-row barley germplasm and interactions between HvAlaAT1 and HvMKK3 were associated with changes in seed dormancy and germination rate over time. Several malting quality traits were associated with HvMKK3 alleles. Kompetitive allele-specific polymerase chain reaction (KASP) markers were developed for the causal mutations in HvAlaAT1 and HvMKK3 and a diagnostic mutation in HvGA20ox1. Haplotypes with PHS resistance, short primary dormancy, and a high germination rate were identified that could be useful for breeding for PHS resistance and malting quality.

中文翻译：

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大麦 SD1 和 SD2 种子休眠位点的相互作用影响收获前发芽、种子休眠和麦芽质量

收获前发芽 (PHS) 会严重损害大麦 ( Hordeum vulgare L.) 的麦芽质量，在收获前后降水频率较高的地区尤其值得关注。麦芽品质和 PHS 抗性通常呈负相关，5H 染色体上的SD2基因座与这两种性状有关。使用三个春季大麦种群，在六个时间点绘制 PHS、种子休眠和发芽率，以确定后熟期这些性状的遗传控制变化。SD1基因座的HvAlaAT1与长期休眠和降低的发芽率有关。对HvGA20ox1进行了 Sanger 测序的 90 行，但变异与 PHS 或发芽性状无关。HvMKK3的等位基因状态与北美春季两行大麦种质中的遗传 PHS 易感性密切相关，HvAlaAT1和HvMKK3之间的相互作用与种子休眠和发芽率随时间的变化有关。几种麦芽品质性状与HvMKK3等位基因有关。为HvAlaAT1和 HvMKK3 中的因果突变以及HvGA20ox1中的诊断突变开发了竞争性等位基因特异性聚合酶链反应 (KASP)标记. 鉴定出具有 PHS 抗性、初级休眠期短和发芽率高的单倍型，可用于 PHS 抗性和麦芽品质的育种。