To achieve malt grade and receive full price, barley (Hordeum vulgare L.) crops must meet standards for certain quality traits including percent plump and protein. Terminal drought stress reduces quality and is projected to worsen in barley cultivation areas, underscoring the need for varieties that maintain good malt production with unreliable precipitation. The stay‐green trait extends the grain fill phase between heading and maturity and has been linked to stable quality under dry conditions. However, this relationship can be inconsistent and is not well understood. To effectively leverage a longer grain fill phenotype for drought adaptation, a better grasp of its genetics and environmental interaction is needed. Stay‐green root system differences have been observed and could be at play. We performed correlation and quantitative trait locus (QTL) analysis on grain fill duration, grain quality, and seminal root traits using a recombinant inbred line (RIL) population segregating for stay‐green. Agronomic data were collected in four field trials at two distinct semiarid locations, and roots were measured in a greenhouse assay. Earlier heading and later maturity led to improved quality in both locations and more consistent quality between locations. Earlier heading had a greater influence on quality in the drier environment, while later maturity was more impactful in the less dry environment. We observed co‐locations of seminal root trait QTLs with grain fill duration and grain quality. These QTLs lay the groundwork for further investigation into root phenotypes associated with stay‐green and the deployment of these traits in breeding for drought adaptation.

中文翻译：

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QTL 作图揭示了两种旱地环境中麦芽大麦品质的改善与籽粒灌浆期延长和种子根性状相关


为了达到麦芽等级并获得全价，大麦 (Hordeum vulgare L.) 作物必须满足某些质量特性的标准，包括丰满度和蛋白质。终末干旱胁迫会降低大麦种植区的质量，预计情况会恶化，这凸显了对在降雨不稳定的情况下保持良好麦芽产量的品种的需求。保持绿色的特性延长了抽穗和成熟之间的籽粒灌浆期，并且与干燥条件下稳定的品质有关。然而，这种关系可能不一致并且未被很好地理解。为了有效利用较长的籽粒灌浆表型来适应干旱，需要更好地掌握其遗传学和环境相互作用。已观察到保持绿色的根系差异，并且可能会发挥作用。我们使用分离保持绿色的重组自交系 (RIL) 群体，对籽粒灌浆持续时间、籽粒质量和种子根性状进行了相关性和数量性状位点 (QTL) 分析。在两个不同的半干旱地点的四次田间试验中收集了农艺数据，并在温室测定中测量了根系。提早抽穗和推迟成熟可以提高两个地点的质量，并使不同地点之间的质量更加一致。在干燥的环境中，提早抽穗对品质的影响更大，而在不太干燥的环境中，晚熟的影响更大。我们观察了种子根性状 QTL 与籽粒灌浆持续时间和籽粒品质的共定位。这些 QTL 为进一步研究与保持绿色相关的根表型以及将这些性状应用于干旱适应育种奠定了基础。