Taylor Michael W, Ferré Céline A M, Ye Shengjian, Yang Xuan, Feurtado J Allan, Beattie Aaron D
Department of Plant Sciences, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, SK, Canada.
Aquatic and Crop Resource Development, National Research Council of Canada, Saskatoon, SK, Canada.
Front Plant Sci. 2025 Aug 28;16:1547207. doi: 10.3389/fpls.2025.1547207. eCollection 2025.
Lodging caused by stem buckling or root anchorage failure results in significant economic losses each year globally due to increased disease load, downgrading of quality, and yield loss. To increase lodging resistance in western Canadian barley, a study was undertaken to identify traits associated to lodging score. Mechanical and architectural traits encompassing whole plant, stem and root features of 13 spring barley genotypes, representing a diversity of classes, height, and lodging resistance, were evaluated at six field locations over three years. Correlation analysis identified plant height, internode length, crown root angle and root system solidity as traits with the largest influence on lodging (r = 0.37, 0.27, -0.32 and 0.62, respectively). A structural equation model (SEM) was created to further evaluate which traits had direct or indirect influence on barley lodging. The best fitting SEM included nine traits that captured aspects of the whole plant, stem and root system. Plant height (effect estimate = 0.46) and root system solidity (0.14) showed a direct influence on lodging, while root angle had both direct (-0.21) and indirect (via height) influence on lodging. Stem strength, stem outer diameter, and stem volume had indirect effects on lodging through height, while root network area, convex area and total root length had indirect effects on lodging through root system solidity. The three traits that directly influenced lodging in both correlation analysis and SEM, plant height, root angle, and root system solidity, displayed moderate to high heritability (0.85, 0.78 and 0.57, respectively), thus making them suitable for breeding selections. Collectively, this study confirmed the role of plant height and root angle in lodging, identified root system solidity as a novel trait associated to barley lodging resistance, and revealed root imaging as a new screening tool to help breeders select for, and improve, lodging resistance in the absence of observable field lodging.
由于病害负荷增加、品质下降和产量损失，全球每年因茎秆弯曲或根系锚固失效导致的倒伏造成了巨大的经济损失。为了提高加拿大西部大麦的抗倒伏能力，开展了一项研究以确定与倒伏评分相关的性状。在三年时间里，对六个田间地点的13个春大麦基因型的机械和结构性状进行了评估，这些性状涵盖了整株植物、茎和根的特征，代表了不同的类别、高度和抗倒伏能力。相关性分析确定株高、节间长度、冠根角度和根系紧实度是对倒伏影响最大的性状（相关系数分别为0.37、0.27、-0.32和0.62）。创建了一个结构方程模型（SEM）来进一步评估哪些性状对大麦倒伏有直接或间接影响。最佳拟合的SEM包括九个捕获整株植物、茎和根系各方面的性状。株高（效应估计值 = 0.46）和根系紧实度（0.14）对倒伏有直接影响，而根角度对倒伏既有直接影响（-0.21）又有间接影响（通过株高）。茎强度、茎外径和茎体积通过株高对倒伏有间接影响，而根网络面积、凸面积和总根长度通过根系紧实度对倒伏有间接影响。在相关性分析和SEM中对倒伏都有直接影响的三个性状，即株高、根角度和根系紧实度，表现出中等至高的遗传力（分别为0.85、0.7 和0.57），因此使其适合用于育种选择。总体而言，本研究证实了株高和根角度在倒伏中的作用，确定根系紧实度是与大麦抗倒伏能力相关的一个新性状，并揭示了根系成像作为一种新的筛选工具，可帮助育种者在没有明显田间倒伏的情况下选择并提高抗倒伏能力。
