镉胁迫对3种蔬菜种子萌发及幼苗生长的影响

Effects of Cadmium(Cd)on Seed Germination and Seedling Growth of Three Species of Vegetables

通过培养皿滤纸萌发试验,研究不同浓度镉胁迫(0、12.5、25、50、100、200mg/L)对3种蔬菜(小白菜、油麦菜和雪里蕻)种子萌发和幼苗生长的影响。结果表明,雪里蕻和油麦菜的发芽率、发芽势在镉离子浓度12.5mg/L时呈不同程度的促进效应,在200mg/L时表现为明显的抑制效应,小白菜的发芽势、发芽率在各浓度组间无显著差异;油麦菜的发芽指数最高;活力指数变化依次为雪里蕻<小白菜<油麦菜;3种蔬菜的根长、芽长均随着镉离子浓度的增加而逐渐减少,且根长的抑制率大于芽长抑制率;镉离子在3种蔬菜中的富集表现为小白菜最低,但当镉离子浓度大于25mg/L时,富集量均超过国家标准,3种蔬菜均不宜食用。

The effects of Cd^(2+) with different concentrations(0,12.5,25,50,100,200mg/L)on the germination and seedling growth of three vegetable seeds(Brassica juncea var.muLticeps,Lactuca sativa var longifoliaf.Lam and Bras⁃sica chinensis L.)were studied by Petri dish filter paper germination experiment.The results showed that 12.5mg/L Cd^(2+) could promote the germination rate and germination potential of B.juncea and L.sativa but 200mg/L Cd^(2+) showed obvious inhibitory effects.There was no significant difference in germination potential and germination rate of B.chinensis between different concentration groups.The germination index of L.sativa was the highest.The change of vitality index was B.juncea<B.chinensis<L.sativa;The root length and bud length of the three vegetables de⁃creased with the increase of cadmium concentration,and the inhibition rate of root length was greater than that of bud length.The enrichment of Cd^(2+) in B.chinensis was the lowest,but when the concentration of Cd^(2+) was greater than 25mg/L,the concentration exceeded the national standard,and the three vegetables were not suitable for eating.