外源MeJA对芜菁幼苗生长及抗氧化酶活性的影响

【目的】研究外源茉莉酸甲酯(MeJA)对芜菁幼苗形态指标及抗氧化酶活性的影响,为茉莉酸参与芜菁抗逆机理提供理论参考。【方法】以温州盘菜和卡玛古两个商业品种的芜菁作为材料,将萌发的芜菁种子培养于添加不同浓度MeJA的1/2MS培养基中,7 d后测定芜菁幼苗的生长指标、渗透调节物质含量、抗氧化酶活性等生理指标。【结果】随着MeJA浓度增加,芜菁幼苗长度及干、鲜重呈降低趋势,叶片中SOD活性先升高后降低,POD、CAT、APX活性逐渐增高,渗透调节物质可溶性糖、可溶性蛋白、脯氨酸含量逐渐增高,MDA、H₂O₂和O₂·^-含量逐渐增高,叶绿素含量逐渐降低。【结论】施加外源MeJA增加了芜菁幼苗的抗氧化酶活性,降低了芜菁幼苗的生长指标,抑制了幼苗的生长。

Effects of Exogenous MeJA on Growth and Antioxidant Enzyme Activity of Turnip Seedlings

【Objective】 Different concentrations of exogenous methyl jasmonate (MeJA) were added to the growth process of turnip, and the effects of morphological indexes and antioxidant enzyme activities of turnip seedlings were measured, aiming at providing theoretical reference for the study of its stress resistance mechanism. 【Methods】 The growth and physiological indexes of turnip seedlings were measured after adding MeJA of different concentrations in 1/2MS medium for 7 days. 【Results】 With the increase of MeJA concentrations, the length, dry and fresh weight of turnip seedlings decreased. The activity of SOD increased first and then decreased, the activity of POD, CAT and APX increased gradually, the contents of soluble sugar, soluble protein and proline, MDA, H₂O₂ and O₂·^- increased gradually, and the content of chlorophyll decreased gradually. 【Conclusion】 The above results showed that exogenous MeJA increased the antioxidant enzyme activity of turnip seedlings, but decreased the growth index of turnip seedlings and inhibited the growth of turnip seedlings.