碘甲磺隆钠盐对土壤中过氧化氢酶活性及呼吸作用的影响

通过模拟实验研究了除草剂碘甲磺隆钠盐对土壤中过氧化氢酶活性和土壤呼吸作用的影响。结果表明,在施用量超过田间推荐用量7倍的浓度范围内,碘甲磺隆钠盐对土壤中过氧化氢酶活性的影响不明显;当其浓度为1mg/kg时,在不同培养时间下,碘甲磺隆钠盐施用后对土壤过氧化氢酶活性的影响呈现出轻微的抑制-激活-恢复的过程;在不同土壤类型中,碘甲磺隆钠盐对土壤过氧化氢酶的抑制性随土壤有机质的增加、pH值的降低而加强;碘甲磺隆钠盐对土壤呼吸作用有一定的影响,浓度愈大,土壤呼吸强度初期抑制愈强,随着时间的推移,逐步由抑制转为一定程度的刺激作用,到12天后施药土壤与对照组土壤的呼吸强度基本上趋于一致。实验结果表明,碘甲磺隆钠盐对土壤微生物影响较小,属于低毒或无实际危害的农药。

EFFECTS OF IODOSULFURON-METHYL-SODIUM ON CATALASE IN SOIL AND SOIL RESPIRATION

Effects of iodosulfuron-methyl-sodium on catalase in soil and soil respiration were studied by simulation in laboratory. The results showed that when the concentration of iodosulfuron-methyl-sodium was 7 times as high as is recommended for field application also had no significant effect on soil catalase activity; But when the concentration was 1mg/kg, the catalase activity of soil was slightly inhibited at first, then stimulated, and at last restored; In the different soils, the higher the organic matter and the lower the pH, the greater the effect of the substance on catalase activity. Iodosulfuron-methyl-sodium also had some effects on soil respiration. The higher the concentration of the substance, the greater the influence in the early days. But as time went by, inhibition was gradually replaced by stimulation. After 12 days respiration of the soil treated with iodosulfuron-methyl-sodium was similar to that in CK. Results of the experiments showed that iodosulfuron-methyl-sodium did little harm to soil microorganisms, and it was a kind of herbicide of low toxicity or no-real harm.