In grasses, biomass and grain production are affected by plant architecture traits such as tiller number, leaf size and orientation. Thus, knowledge regarding their genetic basis is a prerequisite for developing new improved varieties. Mutant screens represent a powerful approach to identify genetic factors underpinning these traits: the HorTILLUS population, obtained by mutagenesis of spring two-row cultivar Sebastian, is a valuable resource for this purpose in barley. In this study, 20 mutant families from the HorTILLUS population were selected and evaluated for tiller number, leaf angle and a range of other plant architecture and agronomic traits using an unreplicated field design with Sebastian as a check cultivar. Principal Component Analysis revealed strong relationships among number of tillers, upper canopy leaf angle, biomass and yield-related traits. Comparison to the Sebastian background revealed that most mutants significantly differed from the wild-type for multiple traits, including two mutants with more erect leaves and four mutants with increased tiller number in at least one phenological stage. Heatmap clustering identified two main groups: the first containing the two erect mutants and the second containing Sebastian and the high-tillering mutants. Among the high-tillering mutants, two showed significantly higher biomass and grain yield per plant compared to Sebastian. The selected mutants represent promising materials for the identification of genetic factors controlling tillering and leaf angle in barley.

在禾本科植物中，生物量和谷物产量受植物结构特征的影响，例如分蘖数、叶片大小和方向。因此，了解其遗传基础是开发新的改良品种的先决条件。突变筛选代表了一种识别支持这些性状的遗传因素的有效方法：通过对春季两行栽培品种 Sebastian 进行诱变获得的Hor TILLUS 种群是大麦中用于此目的的宝贵资源。在这项研究中，来自Hor 的20 个突变家族选择和评估 TILLUS 种群的分蘖数、叶角和一系列其他植物结构和农艺性状，使用非重复田间设计，Sebastian 作为检查品种。主成分分析揭示了分蘖数、冠层叶角、生物量和产量相关性状之间的密切关系。与塞巴斯蒂安背景的比较表明，大多数突变体在多个性状方面与野生型显着不同，包括两个具有更多直立叶的突变体和四个至少在一个物候阶段分蘖数增加的突变体。热图聚类确定了两个主要组：第一个包含两个直立突变体，第二个包含塞巴斯蒂安和高分蘖突变体。在高分蘖突变体中，与塞巴斯蒂安相比，两个显示出显着更高的生物量和单株谷物产量。选定的突变体代表了鉴定控制大麦分蘖和叶角的遗传因素的有希望的材料。