水分胁迫对板栗幼苗叶片活性氧代谢的影响

采用盆栽控水试验测定了板栗幼苗叶片的生理生化指标,结果表明:在土壤水分胁迫下,随胁迫强度的增加,板栗叶片相对含水量和可溶性蛋白含量呈逐渐减小趋势;总叶绿素、叶绿素a、叶绿素b及类胡萝卜素含量呈下降趋势,但下降幅度不同;活性氧保护酶SOD、POD、CAT随胁迫程度的增强呈先降后增再降低的变化趋势,而ASP基本呈降低的变化趋势;O-·2产生速率呈先增再降后增加的变化趋势,而H2O2含量呈先增后降的变化趋势,其中中度胁迫时含量最大;MDA含量与质膜相对透性均随胁迫程度的增强而增大;SOD、CAT、ASP等保护酶可以作为板栗幼苗抗旱力强弱的评价指标.

Effect of So ilWa ter Stress on Active OxygenMetabolism of Chestnut Seedling Leaves

Some indexes, such as the active oxygen p rotective system and some free radicles,were measured by thecontrolling the water in container seedlings. The results indicated that the total relative water contents and the p rotein contents dropped with the increase of stress intensity and the contents of total chlorophyll, chlorophyll a, chlorophyll b and carotinoid had a descending trend. The activities of the SOD, POD and CAT descended firstly, then ascended and descended lastly and the activity of ASP had a descending trend. The free radicles showed differentchanging trend: the O₂ p roducing rates increased firstly, and then decreased and increased lately with the waterstress intensity, but the H₂O₂ contents raised firstly and then decreased. BothMDA content and membrane relativepermeability had an ascending trend with the increasing stress. The activity of the enzymes such as SOD, CAT andASP may evaluate the drought2resistant of the chestnut seedlings as indexes.