毛竹对铀胁迫的生理响应与富集特性研究  

Physiological Response and Enrichment Characteristics of Phyllostachys pubescens to Uranium Stress

作　　者：苟志坤 陈鹏 徐刚[1] 樊伟 龚小强 曹颖[1] 胡尚连[1] GOU Zhikun;CHEN Peng;XU Gang;FAN Wei;GONG Xiaoqiang;CAO Ying;HU Shanglian(Lab of Plant Cell Engineering,College of life Science and Engineering,Southwest University of Science and Technology/Engineering Research Center for Biomass Resource Utilization and Modification of Sichuan Province,Mianyang,Sichuan 621010)

机构地区：[1]西南科技大学生命科学与工程学院,植物细胞工程实验室/四川省生物质资源利用与改性工程技术研究中心,四川绵阳621010

出　　处：《核农学报》2024年第2期404-411,共8页Journal of Nuclear Agricultural Sciences

基　　金：四川省应用基础研究项目(2022NSFSC0093);四川省“十四五”重点攻关项目(2021YFYZ0006)。

摘　　要：为了探究毛竹(Phyllostachys pubescens)对水体铀污染的富集能力,于水培条件下,开展不同浓度铀胁迫对毛竹幼苗的生理影响以及铀富集特征研究。结果表明,随着铀浓度的增加,毛竹叶片的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)和胞间CO_(2)浓度(Ci)均呈现先升高后降低的趋势,其中最高铀浓度400 mg·L^(-1)下的Pn、Tr、Gs分别较对照显著下降了39.71%、18.81%和36.25%,而Ci上升并不明显;毛竹根、茎、叶铀含量逐渐增加,铀转移系数整体呈现先上升后下降的变化趋势,而富集系数整体呈下降态势。此外,毛竹根富集系数高于茎、叶的富集系数,而茎杆的转移系数小于叶部转移系数,但毛竹根、茎、叶对铀的富集和迁移能力不同,较高的根系富集能力可减轻铀对茎叶的毒害作用。在400 mg·L^(-1)铀处理条件下,毛竹地上部和地下部干重、叶绿素a和叶绿素b含量以及超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)活性均较对照显著减少,而丙二醛(MDA)含量却显著增加,说明毛竹对铀具有较强耐受性及较高的富集能力。本研究结果可为毛竹应用于铀污染水体修复提供一定的理论依据和应用价值。In order to investigate the enrichment ability of bamboo(Phyllostachys pubescens)to uranium pollution in water,the physiological response and uranium enrichment characteristics of Phyllostachys pubescens seedlings at different concentrations of uranium stress were studied under hydroponic conditions.As the results,with the increase of uranium concentration,the values of net photosynthetic rate(Pn),transpiration rate(Tr),stomatal conductance(Gs),and intercellular CO_(2)concentration(Ci)in the bamboo leaves increased first and then decreased.Compared to the control group,the values of Pn,Tr,Gs at the highest uranium concentration of 400 mg·L^(-1)decreased greatly by 39.71%,18.81%and 36.25%,respectively,while the increase of Ci concentration was not significant.The uranium contents in the roots,stems,and leaves of bamboo increased gradually,and the uranium transfer coefficient increased and then decreased,but the overall enrichment coefficient showed a downward trend.In addition,the enrichment coefficient of bamboo roots was significantly higher than that of stems and leaves,while the transfer coefficient in stems was smaller than that of leaves.However,the enrichment and migration ability in the bamboo roots,stems and leaves to uranium was different,and a high root enrichment ability could reduce the toxic effect of uranium on stems and leaves.Under 400 mg·L^(-1)uranium treatment,the aboveground and underground dry weight,chlorophyll a and chlorophyll b content,as well as the activities of superoxide dismutase(SOD),peroxidase(POD),catalase(CAT),and ascorbic acid peroxidase(APX)of bamboo decreased dramatically,while the content of malondialdehyde(MDA)increased,indicating that the bamboo had strong tolerance and high enrichment ability to uranium.This study provide a certain theoretical basis for the application of bamboo in the remediation of uranium contaminated water bodies.

关 键 词：毛竹幼苗 铀胁迫 光合作用 抗氧化酶 富集特性 

分 类 号：S795[农业科学—林木遗传育种]