摘要
为揭示植物适应锰胁迫的生理机制,通过在不同Mn^(2+)浓度(0、1、5、10、15、20 mmol/L)下开展盐肤木(Rhus chinensis)种子萌发以及幼苗生长实验,检测锰胁迫处理7、15、30 d后幼苗生理生化特性的变化。结果表明:(1)随着Mn^(2+)浓度的升高,盐肤木种子发芽率变化不显著,在80.0%—81.6%之间,发芽势、发芽指数和活力指数则呈先升后降的趋势;其幼苗生物量也呈现先升后降的趋势;(2)随着Mn^(2+)浓度的升高与胁迫时间的延长,盐肤木幼苗叶绿素a、叶绿素b含量均呈现先增加后降低的趋势,类胡萝卜素含量呈现下降的趋势;(3)胁迫7 d时,随着Mn^(2+)浓度的升高,盐肤木幼苗超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性均显著上升;胁迫15、30 d时,高Mn^(2+)浓度(15—20 mmol/L)下POD、CAT活性则均降低;(4)胁迫7 d时,随着Mn^(2+)浓度的升高,可溶性糖、可溶性蛋白、游离脯氨酸含量升高;胁迫15、30 d时,在Mn^(2+)浓度为20 mmol/L时可溶性蛋白与游离脯氨酸含量显著降低;(5)随着Mn^(2+)浓度的升高与胁迫时间的延长,丙二醛(MDA)含量均升高。研究说明盐肤木具有较强的耐受锰胁迫能力,它可通过增强抗氧化酶活性、积累渗透调节物质含量来应对锰胁迫。
Screening candidate plants and revealing their stress-resistant mechanism are the key to phytoremediation.In order to reveal resistance and the physiological adaptation mechanism of Rhus chinensis to manganese(Mn)stress,the experiments on seed germination and seedling growth of R.chinensis were carried out in this study.We examined the germination and growth of R.chinensis seeds under different Mn^(2+)concentrations(0,1,5,10,15,20 mmol/L),as well as the changes of physiological and biochemical characteristics in leaves of R.chinensis seedlings after 7,15 and 30 days of manganese stress treatment.The results showed that:(1)with the increase of Mn^(2+)concentrations,the germination rate of R.chinensis seeds did not change significantly,ranging from 80.0%to 81.6%,while germination potential,germination index and vigor index increased at first and then decreased;other biomass indexes of R.chinensis seedlings showed a pattern of increased at first and then decreased.(2)The contents of chlorophyll a and chlorophyll b in leaves of R.chinensis seedlings increased at first and then decreased with the increase of Mn^(2+)stress concentration and the extension of stress time,and the carotenoid content showed a downward trend after 30 days of Mn stress.(3)After 7 days of Mn stress,with the increase of Mn^(2+)concentration,the activities of superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT)in leaves of R.chinensis seedlings increased significantly(P<0.05);after 15 and 30 days of Mn stress,all activities of SOD,POD and CAT increased significantly(P<0.05)at low concentration,while at high concentration(15 and 20 mmol/L),the activities of POD and CAT decreased significantly(P<0.05).(4)After 7 days of Mn stress,the contents of soluble sugar,soluble protein and free proline in leaves of R.chinensis seedlings increased significantly(P<0.05)with the increase of Mn^(2+)concentration.After 15 and 30 days of Mn stress,the contents of soluble protein and free proline decreased significantly(P<0.05)when Mn^(2+)concentration was 20 mmol/L,but the soluble sugar did not decrease significantly.(5)With the increase of Mn^(2+)stress concentration and the extension of stress time,the content of malondialdehyde(MDA)in leaves of R.chinensis seedlings increased significantly(P<0.05)after 15 and 30 days of Mn stress.The results of this study show that R.chinensis has a strong ability to withstand manganese stress,which mainly responds to external manganese stress by enhancing the activity of antioxidant enzymes and accumulating a large number of osmotic adjustment substances in plants.
作者
王悟敏
匡雪韶
胡佳瑶
刘文胜
WANG Wumin;KUANG Xueshao;HU Jiayao;LIU Wensheng(School of Life Sciences and Technology,Central-South University of Forestry and Technology,Changsha 410004,China)
出处
《生态学报》
CAS
CSCD
北大核心
2022年第9期3706-3715,共10页
Acta Ecologica Sinica
基金
国家自然科学基金项目(42177018)
湖南省自然科学基金项目(2021JJ31147)
湖南省教育厅项目(20C1917)。
关键词
盐肤木
锰胁迫
种子萌发
幼苗生长
生理特性
Rhus chinensis
manganese stress
seed germination
seedling growth
physiological characteristics
