外源ALA对盐碱胁迫下辣椒幼苗生理生化特性的影响

Physiological and biochemical characteristics effects of exogenous ALA on pepper seedlings under saline-alkali stress

为研究外源ALA对盐碱胁迫下辣椒幼苗生长的影响,以2个辣椒品种G3和G7为试材,盐碱胁迫下喷施5种不同质量浓度(0、10、25、40和60 mg·L^(-1))的ALA溶液。通过对喷施后辣椒幼苗的株高、茎粗、干鲜质量等表型指标和MDA、H2O_(2)等生理指标以及3种抗氧化酶(SOD、POD和CAT)活性进行测定,揭示外源ALA对盐碱胁迫下辣椒幼苗生理生化特性的影响。结果表明,喷施外源40 mg·L^(-1)的ALA能够有效提高盐碱胁迫下辣椒植株的株高、茎粗、叶面积、总根长以及干鲜质量,其中2个品种的叶面积分别升高39.9%和17.1%,根长分别升高18.3%和40.5%;同时提高辣椒幼苗叶片中的可溶性蛋白、可溶性糖的含量,并降低脯氨酸、MDA、H2O_(2)的含量及O_(2)·的产生速率,2个品种辣椒幼苗叶片的SOD活性分别提高了16.0%和17.5%,CAT活性也分别提高了87.8%和354.6%。因此,喷施外源ALA 40 mg·L^(-1)时,对辣椒幼苗受到盐碱胁迫后的缓解作用更大。

In order to study the effect of exogenous ALA on the growth of pepper seedlings under saline-alkali stress,five different concentrations(0,10,25,40 and 60 mg·L^(-1))of ALA solutions were sprayed under saline-alkali stress using G3 and G7 pepper varieties as test materials.The physiological and biochemical characteristics effects of exogenous ALA on pepper seedlings under saline-alkali stress were determined by measuring the phenomorphic indexes such as plant height,stem thickness,dry fresh weight,physiological indexes such as MDA and H2O_(2),and the activities of three antioxidant enzymes(SOD,POD and CAT)of pepper seedlings after spraying.The results showed that exogenous spraying of 40 mg·L^(-1)ALA could effectively increase the plant height,stem thickness,leaf area,total root length and dry fresh weight of pepper plants under saline-alkali stress,and the leaf area of the two cultivars increased by 39.9%and 17.1%,root length increased by 18.3%and 40.5%,respectively.At the same time,the content of soluble protein and soluble sugar in the leaves of pepper seedlings was increased,and the content of proline,MDA,H2O_(2)and O_(2)·production rate were reduced,and the SOD activity of pepper seedling leaves increased by 16.0%and 17.5%,and CAT activity was also increased by 87.8%and 354.6%.Therefore,when the concentration of ALA was 40 mg·L^(-1),the exogenous spraying had a better alleviation effect on pepper seedlings after saline-alkali stress.