Cornwall Joseph, Stubbs Christopher J, McMahan Christopher S, Robertson Daniel J
Department of Mechanical Engineering, University of Idaho, Moscow, ID, United States.
School of Mathematical and Statistical Sciences, Clemson University, Clemson, SC, United States.
Front Plant Sci. 2021 Aug 20;12:617880. doi: 10.3389/fpls.2021.617880. eCollection 2021.
The biomechanical role of the clasping leaf sheath in stalk lodging events has been historically understudied. Results from this study indicate that in some instances the leaf sheath plays an even larger role in reinforcing wheat against stalk lodging than the stem itself. Interestingly, it appears the leaf sheath does not resist bending loads by merely adding more material to the stalk (i.e., increasing the effective diameter). The radial preload of the leaf sheath on the stem, the friction between the sheath and the stem and several other complex biomechanical factors may contribute to increasing the stalk bending strength and stalk flexural rigidity of wheat. Results demonstrated that removal of the leaf sheath induces alternate failure patterns in wheat stalks. In summary the biomechanical role of the leaf sheath is complex and has yet to be fully elucidated. Many future studies are needed to develop high throughput phenotyping methodologies and to determine the genetic underpinnings of the clasping leaf sheath and its relation to stalk lodging resistance. Research in this area is expected to improve the lodging resistance of wheat.
在茎倒伏事件中，紧扣茎的叶鞘的生物力学作用在历史上一直未得到充分研究。本研究结果表明，在某些情况下，叶鞘在增强小麦抗茎倒伏能力方面所起的作用甚至比茎本身更大。有趣的是，叶鞘似乎并非仅仅通过增加茎的材料（即增加有效直径）来抵抗弯曲载荷。叶鞘对茎的径向预紧力、叶鞘与茎之间的摩擦力以及其他几个复杂的生物力学因素可能有助于提高小麦茎的弯曲强度和茎的抗弯刚度。结果表明，去除叶鞘会导致小麦茎出现不同的破坏模式。总之，叶鞘的生物力学作用很复杂，尚未完全阐明。未来需要进行许多研究来开发高通量表型分析方法，并确定紧扣叶鞘的遗传基础及其与抗茎倒伏能力的关系。预计该领域的研究将提高小麦的抗倒伏能力。
