镉锌胁迫对小麦和2种杂草种子萌发及幼苗生长的影响

Effects of Cd^(2+) and Zn^(2+) on Seed Germination and Seedling Growth of Triticum aestivum and 2 Weed Species

以蒸馏水为CK,测定重金属锌、镉单一胁迫对小麦、地肤和稗草种子萌发指标和幼苗生长指标的影响,采用隶属函数法综合评价3种植物对重金属锌、镉的耐性。结果表明:不同植物种子萌发和幼苗生长指标对2种重金属离子胁迫的响应不尽相同,随着Cd^(2+)和Zn^(2+)浓度的增加,除Zn^(2+)浓度50 mg/L下活力指数高于CK外,3种植物种子的相对发芽率、发芽指数和活力指数均有不同程度的降低。随Cd^(2+)浓度的增加,小麦和稗草幼苗的相对根长和相对芽长呈下降趋势,地肤在25 mg/L、50 mg/L的Cd^(2+)浓度处理下幼苗相对根长显著高于CK;在50,100,200和400 mg/L的Zn^(2+)处理下,稗草幼苗的相对根长显著高于CK,在50和100 mg/L的Zn^(2+)处理下稗草幼苗的相对芽长显著高于CK,在50 mg/L的Zn^(2+)处理下小麦和地肤幼苗的相对根长和相对芽长均显著高于CK。耐Cd^(2+)的强弱顺序为地肤>小麦>稗草,耐Zn^(2+)的强弱顺序为稗草>地肤>小麦。在萌发期2种杂草对Cd^(2+)和Zn^(2+)有较强的耐性,在重金属污染治理中有一定的应用潜力。

In this study,distilled water was used as CK to determine the effects of Zn^2+and Cd^2+single stress on seed germination and seedling growth of Triticum aestivum,Echinochloa crusgalli and Kochia scoparia,and the tolerance of 3 kinds of plants to Zn^2+and Cd^2+was evaluated by membership function method.The results show that the response of the seeds germination and seedling growth of different seeds are not the same under the 2 metal ions stresses.With the increase of Cd^2+and Zn^2+concentration,the relative seed germination rates,germination indices and the vigor indices of 3 kinds of plants decreased except that the vigor indices is higher than CK under 50 mg/L Zn^2+concentration.With the increase of Cd^2+concentration,the relative root length and relative shoot length of T.aestivum and E.crusgalli seedlings decrease and the relative root length of K.scoparia seedlings is significantly higher than CK under 25 and 50 mg/L Cd^2+concentration.The relative root length of E.crusgalli seedlings treated with Zn^2+of 50,100,200 and 400 mg/L are significantly higher than CK.The relative shoot length of E.crusgalli seedlings treated with 50 and 100 mg/L Zn^2+are significantly higher than CK.The relative root length and relative shoot length of Triticum aestivumt and Kochia scoparia seedlings are significantly higher than CK under the treatment of 50 mg/L Zn^2+.The resistance of seed to Cd^2+stress is ordered as K.scoparia >T.aestivum >E.crusgalli,and to Zn^2+stress is ordered as E.crusgalli >K.scoparia >T.aestivum.Comprehensive analysis shows that Kochia scoparia and Echinochloa crusgalli seeds have strong resistance to Cd^2+and Zn^2+respectively during seed germination period.