| 摘要: |
| 一、水培的甘薯离体叶片,其蒸腾强度起初略高于留在植株上的同令叶片,随后因气孔关闭而迅速下降。实验证明,根压的丧失及物理性堵塞均不能说明离体枝叶水培时蒸腾变化的幅度及生理本质。二、离体薯叶经几天水培后,滋生出新的不定根,随着新根的出现及大量形成,蒸腾又恢复正常。若把浸水段上的新根随时摘除,把水面上方的不定根包在塑料袋内,让它们生长又不触及水面,水流仍由下端断口进入。此时,亦可观察到气孔功能的正常恢复及叶面蒸腾的大幅度提高。三、外加的生长素、赤霉素、激动素对蒸腾已降得很低的甘薯叶片的影响很小,它们各自的单独处理不能代替根系的作用。四、本项研究对离体水培枝叶气孔关闭及蒸腾下降现象的解释是。根系可能产生某种微量活性物质,这种物质被输送到叶片,并为气孔功能的正常维持所必需。 |
| 关键词: 不定根 激动素 赤霉素 离体叶片 气孔运动 根系 水培 叶片蒸腾 甘薯叶 蒸腾强度 |
| DOI： |
|
| 基金项目: |
|
|
|
|
|
| Abstract: |
| A single leaf or a stem segment bearing a leaf was detached from the sweet potato plant (Ipomoea batatas) and its lower end immersed in distilled water.Transpiration rate (grams of water lost/hr/dm sq) of the detached leaf was measured at regular intervals in successive days.On the first day it was in general slightly higher than that of the leaf on intact plant.Two days later,the rate rapidly declined to 1/10th of the original and maintained at such a low level consecutive- ly for several days (Fig2).Porom... |
| Key words: |
