短芒披碱草和老芒麦在水分胁迫下游离脯氨酸积累的研究 Ⅱ关于植物间脯氨酸积累差异原因

STUDY ON THE ACCUMULATION OF FREE PROLINE OF ELYMUS BREVIARISTATUS AND E. SIBIRICUS UNDER THE WATER STRESS

本文通过模拟干旱背景研究了短芒披碱草和老芒麦内自由脯氨酸、叶气孔对干旱胁迫的反应和差异。结果表明:短芒披碱草脯氨酸积累速度慢于老芒麦,但气孔相应关闭早于老芒麦,且关闭过程明显的长于老芒麦。脯氨酸积累进程有两个明显的积累临界值:即脯氨酸积累初始临界值和脯氨酸积累显著临界值,这两个值与气孔运动过程同步。据此证明:两种禾草间脯氨酸积累速度、数量决定于叶气孔对干旱胁迫的调控适应性。

Proline content and the aperture of leaf stomata of Elymus breviaristatus and E. sibiricus under water stre-ss was studied. the results showed that the speed of proline accumulation in E. breviaristatus was slower than that in E. sibiricus under the experimental conditions. But the aperture of stomata in E. breviaristatus was nar-rowed earlier and the process of stomatal closure was much longer than those in E. sibiricus. There were two evident threshold in proline accumulation, namely, “the initial threshold of proline accumulation”and “the remarkable threshold of proline accumulation”. The two threshold values were associated with the motion of stomata under the water stress. This suggested that the speed and amount of proline accumulation depend on stomata reaction to drought stress.