【摘要】 采用溶液培养和盆栽实验研究了镉(Cd2+)和铅(Pb2+)对沙打旺种子萌发、幼苗生长、幼苗叶绿体色素含量、脯氨酸含量、抗氧化系统中的2种抗氧化酶(SOD、CAT)活性的影响。Cd2+、Pb2+实验梯度分别为:0,1,2,3,10,20和0,500,1 000,1 500 mg/kg。结果表明,随着Cd2+浓度的增大,种子发芽率、发芽势、发芽指数总体上呈先下降后上升的趋势;随着Pb2+浓度的增大,种子发芽率、发芽势、发芽指数均呈下降趋势,种子发芽进程受到严重抑制。Cd2+和Pb2+对沙打旺幼苗的株高、根长、根重和地上重产生明显的抑制作用。浓度越高,植物生长受到的影响越大。在同一浓度下,Cd2+、Pb2+对沙打旺胚根伸长抑制率大于对芽伸长的抑制率。随着Cd2+、Pb2+浓度的增大,叶绿素含量总体呈下降趋势,但Pb2+对叶绿素的影响大于Cd2+。脯氨酸含量、SOD和CAT的活性均出现低浓度(Cd2+浓度1 mg/kg,Pb2+浓度500 mg/kg)上升,高浓度(Cd2+浓度≥10 mg/kg,Pb2+浓度≥1 000 mg/kg)下降的趋势。更多还原

【Abstract】 The effects of individual Cd2+ and Pb2+ pollution on seed germination,seedling growth,chlorophyll and proline content,and of two antioxidant enzymatic activities(SOD,CAT) in the antioxidant system of A.adsurgens were tested with concentration gradients of Cd2+ and Pb2+ added to water and soil respectively.The concentrations of Cd2+ and Pb2+ were 0,1,2,3,10,20 and 0,500,1 000,1 500 mg/kg respectively.The germination percentage,germination rate and germination indexes all decreased at low Cd2+ concentrations and increased at higher concentrations.They also decreased with a concentration increase of Pb2+.With the same content of Cd2+ and Pb2+,the radicle length was more strongly inhibited than seed elongation.The seedling length,root length,root biomass as well as aboveground biomass were progressively inhibited as concentrations of Cd2+ and Pb2+ increased,but the chlorophyll content decreased.The effect of Pb2+ on the formation of chlorophyll was greater than that of Cd2+.The proline contents and the activities of SOD and CAT tended to increase at lower concentrations(Cd2+ 1 mg/kg,Pb2+ 500 mg/kg) and decrease at higher concentrations(Cd2+ ≥10 mg/kg,Pb2+ ≥1 000 mg/kg).更多还原