Knowledge about the length of xylem vessels is essential to understand water transport in plants because these multicellular units show a 100-fold variation, from less than a centimeter to many meters. However, the available methods to estimate vessel length distribution (VLD) are excessively time consuming and do not allow large and in-depth surveys. Here, we describe a semi-automated method to measure VLD using an automated Pneumatron device. Gas conductivity of a xylem tissue with a certain length is estimated in a straightforward and precise way with the Pneumatron in a way theoretically similar to the air-injection method. The method presented enables fast and easy measurements using multiple devices simultaneously (>50 samples day-1), which is a significant advantage. Here, the apparatus is described in detail as well as how measurements are taken. We also present the software and an R-script for data analysis. The method described represents an important contribution to studies on plant hydraulic architecture and can improve our understanding about the role of VLD in plant performance under varying water availability.

中文翻译：

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一种测量木质部血管长度分布的半自动方法

有关木质部血管长度的知识对于理解植物中的水运输至关重要，因为这些多细胞单元显示出100倍的变化，从不到一厘米到几米。但是，可用的估计血管长度分布（VLD）的方法非常耗时，并且不允许进行大型且深入的调查。在这里，我们描述了一种使用自动Pneumatron设备测量VLD的半自动方法。用气功加速器以直观和精确的方式估算一定长度的木质部组织的气体电导率，其理论上类似于注气法。提出的方法可以同时使用多个设备（第一天> 50个样本）进行快速简便的测量，这是一个显着的优势。这里，详细描述了该设备以及如何进行测量。我们还将介绍该软件和用于数据分析的R脚本。所描述的方法代表了对植物水力结构研究的重要贡献，并且可以增进我们对可变水量下VLD在植物性能中的作用的理解。