摘要
以洋常春藤Hedera helix扦插幼苗为材料,采用不同浓度(0,50,200,400,800μmol·L-1)的Pb(CH3COO)2溶液进行处理,通过测定其叶片叶绿素含量、叶绿素荧光参数的变化,探讨洋常春藤对重金属铅胁迫的抗逆性。结果表明,与对照相比,铅胁迫使洋常春藤叶片叶绿素含量显著下降(P<0.05),叶绿素a/b比值增加;与对照相比,Pb2和Pb3(200和400μmol·L-1)即中度铅胁迫下,洋常春藤叶片初始荧光(F0)和非光化学猝灭系数(qN)显著上升(P<0.05),光系统PSⅡ实际光合效率(Yield)、光化学猝灭系数(qP)以及光合电子传递速率(ETR)显著下降(P<0.05),而PSⅡ最大光化学效率(Fv/Fm)无显著变化;在重度铅胁迫Pb4(800μmol·L-1)下,F0及qN显著上升(P<0.05),其余指标均显著下降(P<0.05)。相关性研究表明,铅胁迫使得洋常春藤叶片的叶绿素a和叶绿素b极显著正相关;其qP与ETR极显著正相关,且两者与Yield均极显著正相关。研究发现,轻度铅胁迫Pb1(50μmol·L-1)虽使得洋常春藤叶绿素含量下降,但对其PSⅡ无明显影响,中度铅胁迫对洋常春藤PSⅡ有一定的影响,而重度铅胁迫会导致其PSⅡ明显的损伤。
In April 2016,half lignification Hedera helix branches were harvested for cutting in Kunming,Yunnan province.In June of the current year,cuttings were treated by different concentrations of Pb2+(0 as CK,50,200,400,800μmol·L-1).60 days later,determinations were implemented on chlorophyll content and chlorophyll fluorescence parameter of cuttings.The result showed that compared with the control,seedlings treated by different concentration of lead had significant low content of chlorophyll content,higher chlorophyll a/b.Under 200 and 400μmol·L-1 of lead stress,minimal fluorescence(F0),non-photo chemical quenching coefficient(qN)of seedlings increased significantly,while yield,photo chemical quenching coefficient(qP),and apparent photosynthetic electron transport rate(ETR)decreased evidently,photochemical efficiency of PSⅡin the light(Fv/Fm)had no evident change.Less than 800μmol·L-1 of lead stress,F0 and qN increased sharply,and the left index decreased evidently.Correlation analysis demonstrated that chlorophyll a had extreme significant relation with chlorophyll b,as well as qP with ETR,both qP and ETR with yield under any lead stress.The experiment concluded that 50μmol·L-1 of lead stress could decreased chlorophyll content,but had no evident effect on PSⅡ,200 and 400μmol·L-1 of lead stress had effect on PSⅡ,800μmol·L-1 of lead stress had great effect.
作者
匡经舸
李琬婷
李响
程小毛
黄晓霞
KUANG Jing-ge;LI Wan-ting;LI Xiang;CHENG Xiao-mao;HUANG Xiao-xia(College of Landscape Architecture and Horticulture,Southwest Landscape Architecture Engineering Research Center of National Forestry and Grassland Administration,Southwest Forestry University,Kunming 650224,China)
出处
《浙江林业科技》
2020年第5期1-6,共6页
Journal of Zhejiang Forestry Science and Technology
基金
云南省应用基础面上项目(2010ZC264)
西南林业大学科技创新基金项目(C16109)。
关键词
洋常春藤
铅胁迫
光合色素
叶绿素荧光参数
Hedera helix
lead stress
photo synthetic pigment
chlorophyll fluorescence parameter
