Here we compare the stomatal conductance (g_s) values obtained with leaf porometer and infra-red gas analyzer (IRGA) in different species subjected to different water availability and evaluated in two different environmental conditions. Sunflower, maize, bean, and grapevine were subjected to two treatments of water availability: well-watered and progressive water stress for 3 days and evaluated in two different times with contrasting environmental conditions. The g_s was determined both on the abaxial and adaxial side of leaves using a leaf porometer and an IRGA. The measured g_s strongly differed between IRGA and porometer, in a way that depended on the species, as well as water availability and environmental conditions. Under maximum water stress, g_s measured with leaf porometer was higher than those measured with IRGA in the four species studied. The present results question the use of usual methodologies for the estimation of g_s, suggesting that g_s would not only depend on the environmental conditions and the water status of the plants, but also on the method used to measure it.

中文翻译：

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对比叶片孔隙率仪和红外气体分析仪的方法：关于气孔电导率测量的旧范式

在这里，我们比较了在不同水质条件下，使用叶片孔率仪和红外气体分析仪（IRGA）获得的气孔电导（g _s）值，并在两种不同的环境条件下进行了评估。对向日葵，玉米，豆类和葡萄进行了两种水分利用处理：浇水充足和进行中的水分胁迫持续3天，并在两个不同的时间（与环境条件形成对比）进行评估。g _s是使用叶片孔度计和IRGA在叶片的正反两面测定的。所测得的克_š IRGA和气孔计之间强烈不同，在某种程度上依赖于物种，以及水的供应和环境条件。在最大水分胁迫下，g在所研究的四个物种中，用叶片孔度计测量的_s高于使用IRGA测量的s。目前的结果质疑了使用常规方法估算g _{s的可能性}，这表明g _s不仅取决于环境条件和植物的水分状况，而且还取决于测量它的方法。