茉莉酸对苹果幼树抗旱效应的研究

Effect of jasmonic acid on the drought-resistance in Malus plants

苹果幼苗经 50 mg/L JA处理 4d后用 PEG60 0 0进行干旱胁迫。在胁迫的 6h内 ,叶片气孔导度表现出“快—慢—快—慢”的降低趋势 ,相同浓度的 JA与 ABA使受旱植株叶片脯氨酸含量分别提高 0 .85mg/g FW～ 1 .30 mg/g FW和 0 .64mg/g FW～ 0 .99mg/g FW,SOD活性分别提高 1 .0 8unit/( mg蛋白· min)～ 1 .78unit/( mg蛋白· min)和0 .89unit/( mg蛋白· min)～ 1 .56unit/( mg蛋白· min)。相同浓度的 JA的处理效应大于ABA。 ABA预处理没有改变胁迫时叶片的 MDA和内源 ABA含量 ,而 JA则使 MDA含量降低 0 .0 1 μmol/g FW～ 4.0 3μmol/g FW,ABA含量提高 2 9ng/g FW～ 2 1 7ng/g FW。升高或降低的曲线均以 4h为转折点。推测 JA通过促进

Some indexes to drought-resistance, such as stomatal conductance, MDA, proline and ABA content, and activity of SOD in leaves of apple seedlings treated by JA or ABA were measured after PEG-6000 treatment. The results showed that the stomatal conductance of leaves treated by JA oscillated at the period of 1 h when decreasing. When plants were treated by JA or ABA, the proline content of leaf increased 0.85~1.30 and 0.64~0.99 mg/gFW, activity of SOD increased 1.08~1.78 and 0.89~1.56 unit/(mg protein·min). Different with JA+PEG, the content of MDA or ABA showed no significant difference between treatment of ABA+PEG and PEG. There was a obvious inflexion at the 4 h in all curves.