Abstract: Effects of low temperature stress on physiological process of Kentucky bluegrass (-Poa pratensis-) was investigated. The result showed that under 5℃ the stress activities of SOD and CAT increased with the stress time and reached the peak after 4 hours and them SOD and CAT increased with the stress time and reached the peak after 4 hour and then decreased. Under 0℃ and 6℃ enzyme activities decreased sharply and almost reached the zero. The enzyme activities of 6℃ decreased than that of 0℃. The chlorophyll and carotin contents decreased with the stress time and the lower of temperature was the faster it decreased. Under 5℃ the proline content remained unchanged and under 5℃ and 0℃ it increased significantly with the stress time. Under 5℃ and 0℃ membrane relative penetration remained unchanged and under 6℃ it increased significantly. The order of sensitivity to low temperature stress is SOD,CAT>carotin>proline>chlorophyll>membrane relative penetration.

Key words: Kentucky bluegrass, Low temperature stress, Physiological and biochemica index process

摘要： 研究低温胁迫对草地早熟禾生理生化指标的影响。结果表明,在5℃下,超氧化物岐化酶(SOD)和过氧化氢酶(CAT)的活性随着胁迫时间的延长而增加,当4h时出现最大值,之后活性逐渐下降。当温度为0℃与-6℃时,两种酶的活性随着胁迫时间的延长而急剧下降,接近于零,温度越低,下降越快。叶绿素和类胡萝卜素含量随着肋迫时间的延长而下降,温度越低下降越快。5℃对脯氨酸含量无明显影响,在0℃与-6℃时,随着时间的延长,含量则明显增加。5℃和0℃低温胁迫对质膜相对透性无明显影响,-6℃时,质膜相对透性明显增大。供试指标对低温胁迫敏感性的顺序是:超氧化物岐化酶、过氧化氢酶>类胡萝卜素>脯氨酸>叶绿素>质膜相对透性。

关键词: 草地早熟禾, 低温胁迫, 生理生化指标