茉莉酸对苹果幼树抗旱效应的研究

苹果幼苗经50mg/LJA处理4d后用PEG6000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/gFW～1.30mg/gFW和0.64mg/gFW～0.99mg/gFW，SOD活性分别提高1.08unit/(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0.01μmol/gFW～4.03μmol/gFW，ABA含量提高29ng/gFW～217ng/gFW。升高或降低的曲线均以4h为转折点。推测JA通过促进ABA合成而增强苹果对干旱的适应能力。

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

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.