铅与丁草胺的交互作用对油麦菜生长和抗氧化酶活性的影响

盆栽土培试验研究了重金属铅与除草剂丁草胺的复合污染对油麦菜生长及生理生化的毒性效应.结果表明土壤铅浓度小于500mg.kg-1对油麦菜发芽率的影响不明显,铅浓度为150mg.kg-1对油麦菜株高有促进作用,但对叶片过氧化物酶（POD）和过氧化氢酶（CAT）活性有明显抑制作用.土壤铅浓度为500mg.kg-1时,油麦菜根...

The influence of Pb2+ and butachlor interaction on growth and antioxidant enzyme activities of Lactuca Sativa L.

The pot experiment was conducted to study the toxic effects of combined pollution of Pb²⁺ and butachlor on the growth and physiology of Lactuca sativa L. The results indicated that germination rates of L. sativa were not obviously affected when the Pb²⁺ concentration was below 500 mg·kg^-1. With the concentration of added Pb²⁺ of 150 mg·kg^-1, the plant height was increased, but activities of peroxidase (POD) and catalase (CAT) in leaves were evidently inhibited. When the concentration of added Pb²⁺ reached 500 mg·kg^-1, the root vitality and POD and CAT activities in leaves were inhibited; the inhibition effect was enhanced when the Pb²⁺ concentration was increased. Experiments with butachlor at concentrations of 2~6 mg·kg^-1 showed inhibition effects on plant height, biomass, root weight and vitality, and POD and CAT activities in leaves. Further experiments with combination of two pollutants showed lower germination rates of L. sativa when the concentration of complex pollution was increased. At both low and high concentrations, the root weight of L. sativa was most severely inhibited and the root vitality was least affected, but the chlorophyll content in leaves was increased. Pb²⁺ and butachlor at low concentrations had synergistic effects on the inhibition of biomass and antagonistic effects on the inhibition of root vitality, POD and CAT activities. However, at high concentrations, the two pollutants had synergistic effects on inhibition of plant height, biomass and root vitality, and antagonistic effects on inhibition of POD and CAT activities. Additionally, Pb²⁺ and butachlor demonstrated synergistic effects on chlorophyll biosynthesis.