PEG6000渗透胁迫对马铃薯生理特性的影响

Effect of Osmotic Stress with PEG6000 on Physiological Characteristics of Potatoes

采用聚乙二醇(PEG)渗透胁迫的方法,研究了不同浓度PEG胁迫对5个马铃薯品种叶片的渗透调节物质与保护酶活性以及丙二醛(MDA)含量的影响。结果表明:脯氨酸(Pro)含量、可溶性蛋白含量随胁迫加剧呈现一直升高的变化趋势,且与品种抗旱性呈负相关关系;过氧化物酶(POD)随胁迫加剧呈现先升高后下降的变化趋势,抗旱性强的品种表现出更强的POD活性;超氧化物歧化酶(SOD)在轻度胁迫下活性下降,在中、重度胁迫下除04-6品系之外全部表现有活性上升的趋势,但与品种的抗旱性均未表现出明显的相关规律;丙二醛(MDA)在轻中度胁迫下含量上升,与品种抗旱性呈显著负相关(r=-0.9363),重度胁迫下,品种间表现虽有不同,但其含量的高低与品种抗旱性关系仍表现为负相关关系。

By using polyethelene glycol （PEG） osmotis stress method, the effect of PEG was studied on leaf osmotic control materials, protective enzymes and the contents of maloneliadehyde （MDA） in five pototo clones. The contents of proline and soluble protein were increased with the increase in PEG concentration, and both were negatively correlated to the drought resistance. The activity of peroxidase （POD） were increased at the beginning and decreased later, and high drought-resistant clones showed strong POD activity. Superoxide dismutase （SOD） activity under mild osmotic stress dropped down. In severe stress, except for the clone 04-6 all had active rising, but it did not show obvious correlation with the drought resistance. MDA content increased under mild and moderate stress, and a significant negative correlation with the drought resistance （r=-0.9363） was found. Under severe stress, no consisitent trend was found in the five clones, but a negative relationship was still obivious.