锶在蚕豆中的富集特征及其对抗氧化酶活性的影响

Strontium Accumulation Characteristics in Vicia faba L. and Its Effect on the Antioxidant Enzyme Activities

为探明锶对蚕豆生长及抗氧化酶活性的影响,以青海9号蚕豆幼苗为试验材料,施加不同浓度锶(25、150、750和1 500 mg·kg^(-1))土培处理30 d,研究不同浓度锶处理对蚕豆体内锶的富集,分布特征,生长指标以及丙二醛(MDA)含量,超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性的影响。结果表明,不同浓度锶处理下,蚕豆幼苗的根长、株高、生物量随着土壤中锶浓度的升高呈先增加后降低的趋势;蚕豆的根、茎、叶均能富集锶,但富集锶的能力在不同器官之间存在显著差异,表现为根>叶>茎,随着处理中锶浓度的升高而增加;MDA含量随着锶浓度增加呈先降低后增加的趋势,而SOD、POD和CAT活性均随着锶浓度增加呈先升高后降低的趋势。综上,蚕豆的根、茎、叶均能积累锶,且以根部的富集能力最强。低浓度锶(<750 mg·kg^(-1))可以诱导蚕豆中抗氧化酶活性增强,提高其抗胁迫的能力,而高浓度锶(1 500 mg·kg^(-1))则抑制蚕豆的抗氧化酶活性。本研究为锶胁迫对植物的生理生态效应提供了理论依据。

To investigate effect of strontium on the growth and antioxidant enzymes activities of broad beans, broad bean seedlings named＇ Qinghai 9＇ were chosen as experimental materials, with different concentrations of strontium treatments （25, 150, 750 and 1500 mg· kg^-1） applied in soil. After 30 days of cultivation, the strontium accumulation and distribution characteristics, growth index, POD, SOD and CAT activity of broad beans were determined. The results showed ： root length, plant height and plant biomass of broad bean seedlings were first increased and decreased later with the strontium concentrations in soils; the root, stem and leaf of broad bean could absorb a certain amount of strontium, whereas strontium uptake ability of organs followed the order of root 〉 leaf 〉 stem. Meanwhile, the strontium concentrations of broad beans increased with the strontium treatments; the MDA content decreased first and increased later as strontium concentration increased, whereas the POD, SOD and CAT activity showed an inverse pattern as strontium concentration increased. In conclusion, the root, stem and leaf of broad bean could accumulate strontium, and the strontium concentration of different organs increased with the strontium concentration in soils, and strontium was mainly concentrated in the root. Low （1 500 mg·kg^-1） concentrations （ 〈 750 mg·kg^-1） of strontium showed the positive effect on the activities of antioxidant enzymes, whereas high Sr concentrations （ 1 500 mg·kg^-1） has the negative effect. This study provided a theoretical support for the plant physiological and ecological effects of strontium.