Cd、Pb复合胁迫对狼尾草种子萌发及幼苗生长的影响  

Effects of Combined Stress of Cd and Pb on Seed Germination and Seedling Growth of Pennisetum alopecuroides

作　　者：国伟强 杜雪 彭玉兰 李源恒 赵春莉[1] 曲同宝[1] GUO Weiqiang;DU Xue;PENG Yulan;LI Yuanheng;ZHAO Chunli;QU Tongbao(College of Horticulture,Jilin Agricultural University,Changchun 130118,China)

机构地区：[1]吉林农业大学园艺学院,长春130118

出　　处：《种子》2021年第11期91-96,共6页Seed

基　　金：国家自然科学基金(42077443);吉林省科技发展计划项目(20190303078 SF)。

摘　　要：为探讨Cd、Pb单一胁迫及复合胁迫对狼尾草(Pennisetum alopecuroides)种子萌发及幼苗生长的影响,采用培养皿发芽法,测定不同处理下狼尾草发芽率、发芽指数、根长、芽长、可溶性蛋白含量、丙二醛(MDA)含量、SOD和POD活性。结果表明,低浓度(≤20 mg·L^(-1))Cd单一胁迫促进狼尾草种子萌发及幼苗生长,高浓度则存在明显的抑制作用;Pb单一胁迫抑制狼尾草种子萌发及幼苗生长;Cd、Pb复合胁迫比单一胁迫抑制作用更明显,胁迫浓度为Cd 80 mg·L^(-1)+Pb 1 000 mg·L^(-1)时狼尾草种子发芽率、发芽指数、根长、芽长达到最低值,与对照相比分别下降了41.54%、41.54%、89.62%、75.40%。狼尾草幼苗可溶性蛋白含量、SOD活性在Cd、Pb单一胁迫下呈先升后降趋势,在复合胁迫下持续降低;狼尾草幼苗MDA含量、POD活性随着胁迫浓度的升高呈上升趋势。狼尾草对2种重金属均有一定的耐受性,且耐性表现为耐Cd大于耐Pb。To investigate the effects of single and combined stress of Cd and Pb on seed germination and seedling growth of Pennisetum alopecuroides, the germination rate, germination index, root length, bud length, soluble protein content, malondialdehyde(MDA) content, SOD and POD activities of P. alopecuroides under different treatments were determined by germinating method in petri dish. The results showed that low concentration of Cd(≤20 mg·L^(-1)) promoted seed germination and seedling growth, while high concentration inhibited seed germination and seedling growth, while the single stress with Pb inhibited seed germination and seedling growth of P. alopecuroides. The inhibition effect of combined stress of Cd and Pb was more obvious than that of single stress under the stress concentration being 80 mg·L^(-1)Cd with 1 000 mg·L^(-1)Pb, the seed germination rate, germination index, root length and bud length reached the lowest value. Compared with the control, the scores decreased by 41.54%, 41.54%, 89.62% and 75.40% respectively. The soluble protein content and SOD activity of P. alopecuroides seedlings increased first and then decreased under single stress of Cd and Pb, and continued to decrease under combined stress, while MDA content and POD activity of P. alopecuroides seedlings increased with the increase of stress concentration. There was a certain tolerance to both heavy metals, and the tolerance was Cd>Pb.

关 键 词：重金属 复合胁迫 狼尾草 种子萌发 生理特性 

分 类 号：S543.9[农业科学—作物学]