| 摘要: |
| 为了解抗寒性不同的厚皮甜瓜品种“玉金香”和“白兰瓜”在低温胁迫下的抗寒生理反应,以20 ℃为对照温度,分别在4,6,8 ℃下低温胁迫6 h,在6 ℃下低温胁迫2,4,6 h后,测定幼苗叶片的抗寒性生理生化指标。结果表明,两品种随温度降低和低温处理时间的延长,其电导率增大,SOD、POD和CAT活性上升,可溶性蛋白含量也呈增加趋势,但抗寒性强的品种在低温下的电导率较低,SOD、POD和CAT等保护酶活性较高,并且能够产生更多的可溶性蛋白。在6 ℃下胁迫6 h后,抗寒性强的“玉金香”电导率较对照增加幅度比抗寒性弱的“白兰瓜”低69%;在4℃下胁迫6 h后,“玉金香”CAT活性较对照增加幅度比“白兰瓜”高122%。由此得出,在低温胁迫下,抗寒性强的厚皮甜瓜品种自身膜系统稳定性较强,保护酶类活性较高,而且可溶性蛋白含量也较大,从而降低了低温给细胞带来的伤害。 |
| 关键词: 厚皮甜瓜 抗寒性 电导率 保护酶 可溶性蛋白 |
| DOI： |
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| 基金项目:陕西省科技攻关项目（2004K01-G11） |
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| Effects of chilling stress on chill-resistance physiological and biochemical indexes of muskmelon seedlings |
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| Abstract: |
| In order to know the physiological reaction of chill resistance in the leaves of different chilling sensitive muskmelon cultivars,the normal temperature 20 ℃ (controled) was taken as the comparison,under 4 ℃,6 ℃,8 ℃ low temperatures two muskmelon cultivars was forced 6 hours and under 6 ℃ being forced 2 h,4 h,6 h separately,and thus the physiological and biochemical indexes related to chill resistance in the leaves of two different chilling sensitive muskmelon cultivars “Yujinxiang” and “Bailangua” were investigated.The results showed that as the temperature dropped and low temperature treatment time extended,the electric conductivity increased,the activity of superoxide dismutase (SOD),peroxidase (POD) and Catalase (CAT) raised in two cultivars,and the content of soluble protein increased.The high chilling resistant cultivar showed lower electric conductivity，higher activities of SOD,POD and CAT,and induction of more soluble protein content.When being forced 6 hours under 6 ℃,in contrast to the comparison,electric conductivity of the high chilling resistant cultivar,“Yujinxiang” is 69%,lower than the low chilling resistant cultivar “Bailangua”.When under 4 ℃ low temperature being forced 6 h,activities of CAT of “Yujinxiang” is 122% higher than that of the low chilling resistant cultivar “Bailangua”.Therefore,the chilling resistant muskmelon cultivar showed stronger stability of membrane,higher activities of protective enzyme and more content of soluble protein,thus reduced injury that the low temperature brings about to the cell. |
| Key words: muskmelon seedling,chill-resistance,electric conductivity,protective enzyme,soluble protein |
