3D deformation field in growing plant roots reveals both mechanical and biological responses to axial mechanical forces.
3D deformation field in growing plant roots reveals both mechanical and biological responses to axial mechanical forces.
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DOI：
10.1093/jxb/erw320
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发表时间：
2016-10
影响因子：
6.9
通讯作者：
Dupuy LX
中科院分区：
文献类型：
--
作者：
Bizet F;Bengough AG;Hummel I;Bogeat-Triboulot MB;Dupuy LX
自由生长的根部施加的最大轴向压力受到根部屈曲的限制，但在提供根部侧向支撑时会增加。土壤中的坚固区域和物理屏障可能会减缓根部伸长，导致水分和养分吸收减少以及产量下降。在这项研究中，通过结合 3D 实时成像、运动学和新型机械传感器来评估根对轴向机械力的生物力学响应。该系统量化了完整杨树根部的杨氏弹性模量 (32MPa)、快速 <0.2 mN 的触摸伸长灵敏度以及生长根部施加的导致弯曲的临界伸长力。运动学分析揭示了 3D 伸长率和曲率的多相生物力学响应。根据欧拉屈曲模型准确预测了测量的临界伸长力，表明在这段短时间内没有生物介导的机械力调节影响弯曲。当通过根部的侧向支撑防止屈曲时，生长的根部施加的力增加了 15 倍以上。生长区和成熟区之间的交界处被确定为机械薄弱区，这似乎对弯曲过程至关重要。这项工作确定了机械约束下根系生长和屈曲的关键限制因素。这些发现与作物和土壤科学相关，并增进了我们对异质结构土壤中根系生长的理解。
Maximal axial pressures exerted by freely growing roots are restricted by root buckling but are increased when root lateral bracing is provided. Strong regions and physical barriers in soils may slow root elongation, leading to reduced water and nutrient uptake and decreased yield. In this study, the biomechanical responses of roots to axial mechanical forces were assessed by combining 3D live imaging, kinematics and a novel mechanical sensor. This system quantified Young’s elastic modulus of intact poplar roots (32MPa), a rapid <0.2 mN touch-elongation sensitivity, and the critical elongation force applied by growing roots that resulted in bending. Kinematic analysis revealed a multiphase bio-mechanical response of elongation rate and curvature in 3D. Measured critical elongation force was accurately predicted from an Euler buckling model, indicating that no biologically mediated accommodation to mechanical forces influenced bending during this short period of time. Force applied by growing roots increased more than 15-fold when buckling was prevented by lateral bracing of the root. The junction between the growing and the mature zones was identified as a zone of mechanical weakness that seemed critical to the bending process. This work identified key limiting factors for root growth and buckling under mechanical constraints. The findings are relevant to crop and soil sciences, and advance our understanding of root growth in heterogeneous structured soils.
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影响因子：
3
作者：
ERICKSON, RO;SILK, WK
通讯作者：
SILK, WK
影响因子：
5.4
作者：
Merret R;Moulia B;Hummel I;Cohen D;Dreyer E;Bogeat-Triboulot MB
通讯作者：
Bogeat-Triboulot MB
影响因子：
7.4
作者：
Beemster, GTS;Baskin, TI
通讯作者：
Baskin, TI
影响因子：
6.9
作者：
Bizet F;Hummel I;Bogeat-Triboulot MB
通讯作者：
Bogeat-Triboulot MB
DOI：
10.1016/0021-8634(78)90075-6
发表时间：
1978-01-01
期刊：
JOURNAL OF AGRICULTURAL ENGINEERING RESEARCH
影响因子：
--
作者：
DEXTER, AR;HEWITT, JS
通讯作者：
HEWITT, JS