除草剂苯磺隆对麦田土壤酶活性的影响

为了评价施用苯磺隆对土壤环境的生态效应，在大田条件下，研究了苯磺隆对麦田土壤酶活性的影响。结果表明，苯磺隆对土壤过氧化氢酶活性具有激活作用，且浓度越高，激活作用越强；对土壤脲酶活性的影响表现为0.13、0.25和0.50 g·kg-1浓度处理轻微激活，1.00 g·kg-1浓度处理抑制；苯磺隆在处理初期抑制土壤多酚氧化酶活性，喷药后10 d开始激活，至30 d逐渐恢复至清水对照水平；苯磺隆对土壤蔗糖酶活性具有抑制作用。苯磺隆对各土壤酶活性的影响均为短期效应，除1.00 g·kg-1浓度处理外，其余处理酶活性在试验后期均能逐渐恢复至对照水平，对麦田土壤生态系统相对安全。

Effects of Tribenuron methly on Soil Enzymes Activities in Wheat Field

The effects of tribenuron-methly on soil enzymes activities in the field of wheat planted after rice harvest were studied under field conditions to evaluate its environment ecological effects. The concentration of tribenuron-methly was 5 levels,0(water,CK), 0.13, 0.25, 0.50 and 1.00 g·kg~(-1). The differences of activity among enzymes in soil treated with tribenuron-methly were significant. Soil catalase activity was stimulated by tribenuron-methly, and the higher the concentration of tribenuron-methly was, the greater the stimulation was. Urease activity was slightly stimulated by low concentration of tribenuron-methly (0.13、0.25 and 0.50 g·kg~(-1)), but was depressed by high concentration (1.00 g·kg~(-1)). Polyphenol oxidase activity was inhibited in the first 5 day after treatment (DAT), but the inhibition gradually decreased and which was stimulated from the 10th DAT, then the activities stabilized at the control level on the 30th DAT. Invertase activity was inhibited by tribenuron-methly. The effects of tribenuron-methly on activities of soil enzymes were short term effect, they could recover during the period of the experiment (except for 1.00 g·kg~(-1)). It was suggested that lower dosage of tribenuron-methly was relatively safe to soil ecosystem in wheat field.