本文選題：向日葵　切入點(diǎn)：鍶　出處：《環(huán)境科學(xué)學(xué)報(bào)》2017年12期

【摘要】：為探明向日葵(Helianthus annuus L.)對(duì)金屬鍶的富集特征和耐受機(jī)制,本試驗(yàn)施加不同濃度鍶(25、150、750和1500 mg·kg-1)土培處理30 d,研究了向日葵幼苗體內(nèi)鍶的富集和分配特征及對(duì)植物生長和膜脂過氧化產(chǎn)物MDA(丙二醛)含量、SOD(超氧化物歧化酶)、POD(過氧化物酶)、CAT(過氧化氫酶)活性的影響.結(jié)果顯示:(1)向日葵幼苗的根長、株高、根生物量和地上生物量隨著土壤中金屬鍶濃度的升高呈先增加后降低的趨勢(shì);(2)向日葵的根、莖、葉均能富集金屬鍶,不同器官表現(xiàn)為根葉莖.向日葵的生物富集系數(shù)與不同器官金屬鍶富集濃度呈顯著負(fù)相關(guān),且根部金屬鍶濃度與富集系數(shù)的相關(guān)性最強(qiáng);(3)MDA含量隨著鍶濃度升高呈先減少后增加的趨勢(shì),而抗氧化酶SOD、POD和CAT活性均隨著鍶濃度升高呈先增加后減少的趨勢(shì).SOD和POD活性在高濃度金屬鍶處理中受到了抑制,而高水平的CAT活性表明向日葵清除活性氧的能力增強(qiáng).以上結(jié)果表明,向日葵的根、莖、葉均能積累鍶,根部的富集能力最強(qiáng),且根部的抗氧化酶系統(tǒng)對(duì)金屬鍶脅迫更為敏感,其中較高的CAT活性表明在向日葵耐受鍶脅迫機(jī)制中起到關(guān)鍵作用.此研究為金屬鍶污染土壤的植物修復(fù)以及向日葵對(duì)鍶的耐受機(jī)制提供理論依據(jù).
[Abstract]:In order to study the enrichment characteristics and tolerance mechanism of strontium in helianthus annuus L., In this experiment, the enrichment and distribution of strontium in sunflower seedlings and the content of MDA-malondialdehyde (MDA) in plant growth and membrane lipid peroxidation were studied after 30 days of soil culture treatment with different concentrations of Sr 25150750 and 1500 mg kg-1. The superoxide dismutase (superoxide dismutase) and POD (superoxide dismutase) were used to study the effect of soil culture on plant growth and membrane lipid peroxidation. Effects of Oxidase CAT (catalase) activity. The results showed that the root length of sunflower seedlings, Plant height, root biomass and aboveground biomass increased first and then decreased with the increase of the concentration of strontium in soil. The bioconcentration coefficient of sunflower was negatively correlated with the concentration of strontium in different organs. The correlation between strontium concentration and enrichment coefficient was the strongest, and the MDA content decreased first and then increased with the increase of strontium concentration. The activities of SOD and CAT increased first and then decreased with the increase of strontium concentration. The activities of SOD and POD were inhibited by high concentration of strontium. The high level of CAT activity indicated that the ability of scavenging reactive oxygen species was enhanced. The results showed that the roots, stems and leaves of sunflower could accumulate strontium, the enrichment ability of roots was the strongest, and the antioxidant enzyme system of the roots was more sensitive to strontium stress. The higher activity of CAT indicates that it plays a key role in the tolerance mechanism of sunflower to strontium stress, which provides a theoretical basis for the phytoremediation of soil contaminated by strontium and the tolerance mechanism of sunflower to strontium.
【作者單位】： 河南科技大學(xué)農(nóng)學(xué)院;中國科學(xué)院生態(tài)環(huán)境研究中心城市與區(qū)域生態(tài)國家重點(diǎn)實(shí)驗(yàn)室;河南科技大學(xué)食品與生物工程學(xué)院;
【基金】：河南科技大學(xué)青年基金項(xiàng)目(No.2014QN065);河南科技大學(xué)學(xué)科提升振興A計(jì)劃項(xiàng)目(No.13660001) 國家自然科學(xué)基金(No.U1304326)~~
【分類號(hào)】：X173;X591
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本文編號(hào)：1666781