干旱区生态环境知识资源中心(Arid): 胡杨异形叶抗氧化能力的比较

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	胡杨异形叶抗氧化能力的比较
其他题名	Comparative study on antioxidant capacity of heteromorphic leaves of Populus euphratica
	李萍萍; 曾明; 李文海; 赵媛媛; 郑彩霞
来源期刊	北京林业大学学报
ISSN	1000-1522
出版年	2019
卷号	41 期号:8 页码:76-83
中文摘要	【目的】胡杨是我国西部荒漠地区抗逆性较强的树种,具有异叶性。前人的研究发现,胡杨叶片从披针形叶到锯齿卵圆形叶其结构趋于旱生性,且抗性逐渐增强。本文拟从活性氧清除机制着手,深入探讨胡杨异形叶的抗氧化能力,以期阐释其抗逆性的生化机制。【方法】以成年胡杨披针形叶、卵圆形叶和锯齿卵圆形叶3种典型形态叶为试验材料,对其·O_2~-产生速率、MDA含量、抗氧化酶(SOD、POD、CAT、APX、GR)活性和抗氧化物质(黄酮、类胡萝卜素、AsA、GSH)含量随季节(5、7和9月)变化的规律进行了比较研究。【结果】(1)·O_2~-产生速率随季节而变化,·O_2~-产生速率在锯齿卵圆形与卵圆形叶中递增,在披针形叶中先增后减;MDA含量在锯齿卵圆形叶中递减,在卵圆形叶中先减后增,而在披针形叶中持续递增。值得注意的是,9月份披针形叶中·O_2~-产生速率最低而MDA含量最高。(2)锯齿卵圆形叶与卵圆形叶的SOD活性先降后升而CAT活性先升后降,POD活性持续升高而GR活性递减。APX活性在锯齿卵圆形叶中先升后降,在卵圆形叶中一直升高。而披针形叶的SOD、POD、CAT、APX和GR活性均呈先升后降的变化趋势。整体而言,锯齿卵圆形叶的抗氧化酶活性 >卵圆形叶 >披针形叶。其中,POD活性差异最为明显。(3)黄酮和类胡萝卜素在7月份大量积累,9月份AsA含量最高而GSH含量最低。黄酮和类胡萝卜素含量在锯齿卵圆形与卵圆形叶中先增后减,在披针形叶中递增;AsA含量在锯齿卵圆形与卵圆形叶中递增,在披针形叶中先减后增;3种形态叶的GSH含量均递减。(4)锯齿卵圆形叶中·O_2~-产生速率与POD活性及AsA含量呈极显著正相关(P < 0.01),卵圆形叶中·O_2~-产生速率与POD和APX活性及类胡萝卜素和AsA含量存在极显著正相关(P < 0.01),披针形叶中·O_2~-产生速率则与POD、CAT和APX活性及黄酮和类胡萝卜素含量都存在极显著正相关(P < 0.01)。【结论】胡杨3种形态叶的抗氧化能力不同。锯齿卵圆形叶抗氧化能力最强,卵圆形叶次之,披针形叶最弱。3种形态叶随季节变化的抗氧化应答机制也存在差异。夏季锯齿卵圆形叶与卵圆形叶中以POD、CAT和APX作为主要清除ROS的抗氧化酶,秋季则以高活性的SOD和POD作为主要的抗氧化酶。同时,秋季卵圆形叶中APX活性也维持在较高水平。而披针形叶中以SOD、POD、CAT、APX和GR协同清除ROS。此外夏季胡杨叶片大量积累黄酮和类胡萝卜素消除ROS;秋季则通过AsA-GSH循环清除更多的ROS。
英文摘要	[Objective] Populus euphratica, commonly known as a desert poplar, is a pioneer tree species with stress resistance and heteromorphic leaves in western China. Previous studies have demonstrated that the structural characteristics of the diversiform-leaves of P. euphratica are related to its eco-adaptability. In the present study, to elucidate the regulation mechanisms of stress tolerance, we focused on the antioxidant capacity for three types of heteromorphic leaves of P. euphratica. [Method] In this paper, the changes of ·O_2~-production rate, MDA content, antioxidant enzyme activities (SOD, POD, CAT, APX and GR) and antioxidative substance contents (flavone, carotenoid, AsA and GSH) in lanceolate leaves, ovate leaves and dentate broad-ovate leaves, three typical morphological leaves of adult P. euphratica, were studied in different seasons. [Result] The results were as follows: (1) the ·O_2~-production rate and MDA content: with the change of seasons, the rate of ·O_2~-production was progressively increased both in dentate broad-ovate leaves and ovate leaves. While it firstly increased and then decreased in lanceolate leaves. The content of MDA decreased in dentate broad-ovate, firstly decreased and then increased in ovate leaves, while it increased in lanceolate leaves all the time. It is noteworthy that compared with the other types of leaves, ·O_2~-production rate was the lowest while MDA content was the highest in lanceolate leaves in September. (2) The activities of antioxidant enzymes: with the change of seasons, both in dentate broad-ovate leaves and ovate leaves, the activity of SOD firstly decreased and then increased, while the activity of CAT firstly increased and then decreased. There was a progressively increase of the activity of POD, and a decrease of the activity of GR. The activity of APX firstly increased and then decreased in dentate broad-ovate, and it progressively increased in ovate leaves. Remarkably, the activities of SOD, POD, CAT, APX and GR in lanceolate leaves all firstly increased and then decreased. Overall, the activities of antioxidant enzymes were the highest in dentate broad-ovate leaves, followed by ovate leaves, and was the lowest in lanceolate leaves. Furthermore, the difference of POD activity was the most obvious among the three types of leaves. (3) The antioxidative substance contents: in the three heteromorphic leaves of P. euphratica, a large amount of flavone and carotenoid accumulated in July, and AsA content was the highest while GSH content was the lowest in September. The contents of carotenoid and flavone firstly increased and then decreased both in dentate broad-ovate leaves and ovate leaves, while they were increased in lanceolate leaves.
中文关键词	胡杨 ; 异形叶 ; 抗氧化酶 ; 抗氧化剂
英文关键词	Populus euphratica heteromorphic leaf antioxidase antioxidant
语种	中文
收录类别	CSCD
WOS类目	FORESTRY
WOS研究方向	Forestry
CSCD记录号	CSCD:6571273
来源机构	北京林业大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/316271
作者单位	北京林业大学生物科学与技术学院, 北京 100083, 中国
推荐引用方式 GB/T 7714	李萍萍,曾明,李文海,等. 胡杨异形叶抗氧化能力的比较[J]. 北京林业大学,2019,41(8):76-83.
APA	李萍萍,曾明,李文海,赵媛媛,&郑彩霞.(2019).胡杨异形叶抗氧化能力的比较.北京林业大学学报,41(8),76-83.
MLA	李萍萍,et al."胡杨异形叶抗氧化能力的比较".北京林业大学学报 41.8(2019):76-83.