Faculty of Civil Engineering and Mechanics, Kunming University of Science and Technology, Kunming, 650500, Yunnan, China.
Sci Rep. 2020 Sep 7;10(1):14728. doi: 10.1038/s41598-020-71576-9.
Xylem vessels are the channels used for water transport in Jatropha curcas L. Vessel complexity has a great influence on water transport. Therefore, using anatomical experiments and numerical simulations, the water transport characteristics of J. curcas L xylem vessels with perforation plate and secondary wall thickening (pit structures) were analyzed. The results showed that the xylem vessel in J. curcas provided a low resistance path. The xylem vessel resistance was composed of three elements: smooth vessels, secondary wall thickening and perforation plate. The proportion of smooth vessel resistance was the largest, accounting for 66.20% of the total resistance. Then the secondary wall thickening resistance accounted for 30.20% of the total resistance, and finally the perforation plate resistance accounted for 3.60% of the total resistance. The total resistance of the vessel model was positively correlated with the pit depth, perforation plate height and perforation plate width and negatively correlated with the vessel inner diameter and pit membrane permeability. The vessel inner diameter and the pit depth had a great influence on the total resistance. The total resistance of the vessel inner diameter of 52 µm was 89.15% higher than that of 61 µm, the total resistance of the pit depth of 5.6 µm was 21.98% higher than that of 2.6 µm. The pit structure in the secondary wall thickening caused the vessel to be transported radially, and the radial transmission efficiency of the vessel was positively correlated with the pit depth and pit membrane permeability and negatively correlated with the vessel inner diameter. The pit membrane permeability had the greatest influence on the radial transmission efficiency, and its radial transmission efficiency was 0-5.09%.
维管束是麻疯树（Jatropha curcas L.）中用于水分运输的通道。维管束复杂性对水分运输有很大影响。因此，本研究采用解剖实验和数值模拟的方法，分析了具穿孔板和次生壁加厚（纹孔结构）的麻疯树维管束的水分运输特性。结果表明，麻疯树维管束提供了低阻力路径。维管束阻力由光滑导管、次生壁加厚和穿孔板三部分组成。其中，光滑导管阻力占比最大，占总阻力的 66.20%；其次是次生壁加厚阻力，占 30.20%；穿孔板阻力最小，占 3.60%。模型维管束总阻力与纹孔深度、穿孔板高度和穿孔板宽度呈正相关，与导管内径和纹孔膜透过性呈负相关。导管内径和纹孔深度对总阻力影响较大，当导管内径为 52μm 时，总阻力比导管内径为 61μm 时高 89.15%；当纹孔深度为 5.6μm 时，总阻力比纹孔深度为 2.6μm 时高 21.98%。次生壁加厚中的纹孔结构使导管呈径向传输，导管的径向传输效率与纹孔深度和纹孔膜透过性呈正相关，与导管内径呈负相关。纹孔膜透过性对径向传输效率影响最大，其径向传输效率为 0-5.09%。
