| 山桃幼苗响应镉胁迫的生理机制研究 |
| |
| 引用本文： | 罗彩云,王建武.山桃幼苗响应镉胁迫的生理机制研究[J].核农学报,2019,33(10):2068-2076. |
| |
| 作者姓名： | 罗彩云 王建武 |
| |
| 作者单位： | 榆林学院/陕西省陕北矿区生态修复重点实验室,陕西榆林,719000;榆林学院/陕西省陕北矿区生态修复重点实验室,陕西榆林,719000 |
| |
| 基金项目： | 2018年国家大学生创新创业训练计划项目(201838013),榆林市科技局产学研合作项目(2015CXY-03) |
| |
| 摘 要： | 为探究山桃(Amygdalus davidiana)幼苗响应镉(Cd)胁迫的生理机制,通过盆栽试验研究了山桃幼苗在10 mg·kg-1Cd处理后1、15、30、90 d的生理响应和富集特征。结果表明,山桃幼苗叶片O2-·和丙二醛(MDA)相对含量随Cd处理时间的延长而上升,叶绿素a含量、叶绿素b含量、净光合速率(Pn)则逐渐降低。叶绿素a/b值在Cd处理后1~15 d上升,而在30~90 d下降,表明Cd处理前期对叶绿素b的影响较大,而后期主要影响叶绿素a的合成。Mg、Mn元素相对含量随Cd处理时间延长而显著降低,而Cu、Fe含量上升,表明Cd胁迫诱导的山桃幼苗叶绿素合成受限和Pn的降低与Mg、Mn的降低紧密相关,这是由于Mg、Mn分别参与叶绿素合成和光系统Ⅱ(PSII)反应过程。超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性在Cd处理1~15 d显著上升,30~90 d则逐渐降低;过氧化物酶(POD)活性则在处理1~15 d无显著性差异,在30~90 d显著上升;谷胱甘肽还原酶(GR)活性、还原型谷胱甘肽(GSH)和抗坏血酸(AsA)含量均随着Cd处理时间的延长显著上升;ATP硫酸化酶活性和半胱氨酸含量均随着Cd处理时间的延长而显著上升,硫醇代谢物非蛋白硫醇(NPT)和植物螯合素(PCs)在Cd处理前期(1~15 d)差异不显著,而在30 d后显著上升。综上,山桃幼苗在Cd处理前期主要发挥抗氧化酶(SOD、CAT)的功能,并促进抗氧化物质(GSH、AsA)的合成,而Cd处理后期,则以POD、GSH、AsA的功能为主,并增强NPT和PCs的合成,从而促进Cd向液泡中转移,这与Cd处理后期液泡中Cd含量增加的变化趋势一致。本研究结果为山桃可作为重金属植物修复材料提供了理论依据。
|
| 关 键 词： | 镉胁迫 山桃 生理机制 抗氧化酶 液泡 |
| 收稿时间： | 2019-01-07 |
Physiological Mechanism of Amygdalus davidiana Seedlings in Response to Cadmium Stress |
| |
| LUO Caiyun,WANG Jianwu.Physiological Mechanism of Amygdalus davidiana Seedlings in Response to Cadmium Stress[J].Acta Agriculturae Nucleatae Sinica,2019,33(10):2068-2076. |
| |
| Authors: | LUO Caiyun WANG Jianwu |
| |
| Institution: | College of Yulin/Shaanxi Key Laboratory of Ecological Restoration in Shanbei Mining Area, Yulin, Shaanxi 719000 |
| |
| Abstract: | To investigate the potential physiological mechanism of Amygdalus davidiana seedlings in response to cadmium (Cd) stress, a pot experiment was conducted to determine the features of physiological response and Cd enrichment characteristics in Amygdalus davidiana seedlings were analyzed. The obtained results showed that the relative content of O2-· and malondialdehyde (MDA) content in leaves of Amygdalus davidiana seedlings were increased with the Cd treatment time prolonged, while the chlorophyll a and b, and net photosynthesis rate decreased. The ratio of chlorophyll a/b was first increased at the day of 1~15 after Cd stress, while decreased during the day of 30~90. This result indicated that Cd stress mainly affect synthesis of chlorophyll b in the early days of Cd treatment, and then inhibited synthesis of chlorophyll a later. Moreover, the content of Cu and Fe were significantly increased with the Cd treatment time prolonged, while the Mg and Mn content were significantly decreased. Therefore, it was speculated that the inhibited synthesis of chlorophyll a and b, and decreased net photosynthesis rate were mainly attributed to restrained absorption of Mg and Mn under Cd stress. This is because of the critical role of Mg and Mn in process of chlorophyll synthesis and Photoreactive system Ⅱ(PSII), respectively. The activity of superoxide diamutase (SOD) and catalase (CAT) were enhanced under Cd stress at day of 1~15 d, but significantly decreased later. No significant change of peroxidase (POD) activity was observed at day of 1~15, but increased significantly at day of 30~90. On the other side, the glutathione reductase (GR), content of glutathione (GSH) and ascorbic acid increased with the Cd stress time prolonged. ATP sulfurylase activity and cysteine content in seedlings of Amygdalus davidiana were significantly increased with the Cd stress time prolonged. However, the contents of non-protein thio (NPT) and phytochelatins (PCs) were not significantly changed, but the GSH content and Glutathione reductase (GR) activity increased significantly at the early stage (1~15 d) of Cd treatment. With the treatment time prolonged, NPT and PCs content in Amygdalus davidiana seedlings significantly increased. These results indicated that the SOD, CAT, GSH and AsA play a vital role in response to Cd stress during the early stages, and the POD, GSH, AsA, NPT, and PCs mainly function in reversal of Cd stress to activate ROS scavenging system in the later stages. Consequently, the ROS scavenging and compartmentalization of Cd into vacuole were enhanced, and these results were in consistent with the change pattern of Cd content in vacuole with the Cd treatment time prolonged. The findings provide the fundamental information for application of Amygdalus davidiana seedlings in phytoremediation. |
| |
| Keywords: | cadmium stress Amygdalus davidiana lphysiological mechanism antioxidant enzymes vacuole |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
| 点击此处可从《核农学报》浏览原始摘要信息 |
| 点击此处可从《核农学报》下载免费的PDF全文 |
|
