简易注气法测定刺槐木质部导管组织长度

导管组织在木本植物水力学特性及水分关系中的作用逐渐受到关注,但其长度的传统测试装置和方法相对繁琐。本研究在注气法原理基础上进行改进,改进后装置简易、操作便捷。结果表明,本方法可以成功测定刺槐(Robinia pseudoacacia L.)导管的长度及相关参数:气体传导耗散系数为0.111±0.012;最大导管长度为56.9±1.5 cm;平均导管长度为19.6±2.5 cm;最大分布导管长度为9.8±1.3 cm。枝条注气方向对测试结果没有明显影响。测试过程中注气端压强变化不明显,对导管长度及相关参数的测定和计算影响不显著。本方法与传统注气法相比具有更高的精确度。

Xylem Vessel Length Determination in Robinia pseudoacacia L. by Simplified Air Injection

The role of vessel tissues in the hydraulics and water relationships of woody plants has received increasing attention; however, the traditional devices and methods used for determining their length are relatively cumbersome. We designed a simple device for vessel length assessment based on the principle of gas injection, and simplified the measurement process. Results showed that the designed device successfully assessed the vessel length of Robinia pseudoacacia L. with a dissipation coefficient of 0.111±0.012, maximum vessel length of 56.9±1.5 cm, mean vessel length of 19.6±2.5 cm and mode vessel length of 9.8±1.3 cm. There were no significant differences between the gas injected vessel lengths from either side of the stem. The gas pressure in the injection side did not vary significantly during measurement, and had no influence on the test. The present method was found to be more precise than that of traditional air injection.