低温胁迫对草地早熟禾抗性生理生化指标的影响

Effect of Low Temperature Stress on Physiological Process of Kentucky Bluegrass

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 4 h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 >

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.