Fuhrman M H, Koukkari W L
Chronobiologia. 1982 Jan-Mar;9(1):21-32.
Diffusive resistance of the upper and lower leaf surfaces of Abutilon theophrasti Medic, was measured with an automatic diffusive resistance meter. Plants were maintained in growth chambers under 4 different environments: 1. high humidity, well-watered, 2. high humidity, dry, 3. low humidity, well-watered, 4. low humidity, dry. Diffusive resistance measurements were obtained every 4 h for up to 3 days when the plants were subjected to either daily regimes consisting of 15 h of light followed by 9 h of darkness or to continuous illumination. Leaf movements were also monitored. Diffusive resistance was rhythmic (circadian) under all the environmental conditions examined. The pattern of diffusive resistance was the same regardless of whether the humidity and/or soil moisture were high or low. The rhythms of diffusive resistance of the upper and lower leaf surfaces differed, however, in amplitude and in the phase at which the minimum value was reached. Diffusive resistance of the leaf was highest (peak of the rhythm) when the leaf blade was in a nearly horizontal position.
用自动扩散阻力仪测定了苘麻上下叶表面的扩散阻力。将植株置于4种不同环境的生长室中：1. 高湿度、充分浇水；2. 高湿度、干燥；3. 低湿度、充分浇水；4. 低湿度、干燥。当植株接受15小时光照后9小时黑暗的每日光照制度或持续光照时，每4小时进行一次扩散阻力测量，持续3天。同时监测叶片运动。在所研究的所有环境条件下，扩散阻力都呈现出节律性（昼夜节律）。无论湿度和/或土壤湿度是高还是低，扩散阻力模式都是相同的。然而，上下叶表面扩散阻力的节律在幅度和达到最小值的相位上有所不同。当叶片处于几乎水平位置时，叶片的扩散阻力最高（节律峰值）。
