脱落酸预处理对低温胁迫下豇豆幼苗生理生态的影响

Effect of Abscisic Acid on Eco-physiological Characteristics of Cowpea Seedlings Under Low Temperature Stress

以豇豆幼苗为试验材料,在10℃低温处理的同时用0、10、30、40 mg·L^(-1)脱落酸(ABA)喷施豇豆幼苗叶片,探讨外源ABA对蔬菜低温胁迫的缓解效应,以期为合理利用ABA提高蔬菜抗冷特性提供参考。结果表明:ABA预处理能不同程度提高豇豆幼苗生物量、相对含水量、光合色素含量、可溶性蛋白质含量、脯氨酸含量、可溶性糖含量、抗氧化酶活性,降低其相对电导率及丙二醛含量,且10 mg·L^(-1) ABA预处理后豇豆幼苗生物量、相对含水量显著高于对照,叶绿素总量、类胡萝卜素含量分别较对照增加15.22%、20.47%,可溶性蛋白质、脯氨酸、可溶性糖含量均显著高于对照,同时超氧化物歧化酶、过氧化氢酶活性分别较对照增加64.46%、32.59%,且相对电导率及丙二醛含量显著降低。因此,喷施外源ABA能有效提高豇豆幼苗抗寒性,缓解低温的胁迫,且10 mg·L^(-1)外源ABA表现最佳。

The alleviating effect of exogenous abscisic acid(ABA)for vegetables under low temperature stress was studied via a pot experiment using cowpea seedlings to provide a reference for rational use of ABA to improve the cold resistance of vegetables.The cowpea seedlings were foliage sprayed with different concentrations ABA(0,10,30,40 mg·L-1),and the treatments were put under low temperature stress(10℃).The results showed that ABA pretreatment could increase the biomass,relative water content,photosynthetic pigment content,the contents of soluble protein,proline,soluble sugar,and antioxidant enzyme activities,decrease the relative conductivity,malondialdehyde content of cowpea seedlings to different degrees.When the ABA concentration was 10 mg·L-1,the biomass and relative water content significantly higher than the control,the contents of total chlorophyll and carotenoid increased by 15.22%and 20.47%,respectively,compared to control.The contents of soluble protein,proline,soluble sugar were significantly higher than the control,the activities of superoxide dismutase and catalase increased by 64.46%and 32.59%,respectively compared to control.The relative conductivity and malondialdehyde content were significantly reduced.In conclusion,foliage spraying with ABA could improve the cold resistance of cowpea seedlings and alleviate the stress of low temperature significantly,and the ABA of 10 mg·L-1 was the best.