铜-磺胺嘧啶复合胁迫对蔬菜种子发芽的急性毒性效应

研究了黄潮土中常用兽药磺胺嘧啶(SD)与重金属铜(Cu)单一及复合污染对小白菜和西红柿种子发芽(发芽率、根伸长、芽伸长)的影响,分析了土壤中药物浓度与作物生长抑制的剂量-效应关系及复合污染的毒性效应。结果表明,无论是在Cu或SD单一污染物作用下,根伸长和芽伸长抑制率与污染物浓度显著相关(P0.01),发芽抑制率与污染物浓度不相关(P0.05);污染物对根伸长及芽伸长的抑制高于对种子发芽的抑制;SD对2种作物的毒性效应明显强于Cu,SD对小白菜和西红柿根伸长的ID50(抑制率为50%时污染物浓度)分别为1.7和33.6 mg·kg~(-1),而Cu为273.6和457.7 mg·kg~(-1)。Cu-SD复合污染,对西红柿的根和芽伸长的拮抗作用显著(P0.01);但对小白菜来说,在低浓度Cu(100 mg·kg~(-1))作用下,二者的联合拮抗作用不显著(P0.05),随Cu的增加,拮抗作用显著(P0.01)。

Acute Toxic Effect of Cu-Sulfadiazine Combined Stress on the Germination of Vegetable Seeds

This study reported the single and joint effects of commonly used sulfadiazine (SD) veterinary drug and copper (Cu) on the seed germination (including germination rate, root and shoot elongation) of pakchoi and tomato in yellow fluvo-aquic soil, analyzed the dose-response relationship between the drug concentration in soil and inhibitory action on crop growth, as well as toxic the effect of combined pollution. The results indicated that the inhibitory rate of root and shoot elongation correlated significantly with pollutant concentration (P <0.01), the inhibitory rate of germination and pollutant concentration were uncorrelated (P >0.05), whether in the presence of individual Cu or SD; the inhibitory effect of pollutants on root and shoot elongation was much stronger than that of on the seed germination; the toxic effect of SD was much stronger than that of Cu, the ID₅₀ (half inhibition concentration) values of SD on root elongation of pakchoi and tomato were 1.7 and 33.6 mg·kg^-1, respectively, while Cu were 273.6 and 457.7 mg·kg^-1. The antagonism effect of Cu-SD combined pollution on the root and shoot elongation of the tomato was remarkable (P <0.01); but for the pakchoi, the combined antagonism effect was not significant when the Cu concentration was lower than 100 mg·kg^-1 (P >0.05), the antagonism effect was gradually notable as the increasing of the Cu concentration (P <0.01).