百菌清对土壤微生物数量和酶活性的影响

在模拟土壤生态系统中研究了百菌清对土壤微生物数量和酶活性的影响。结果表明,百菌清对细菌表现出明显抑制效应,药剂处理21d后才有所恢复;百菌清对放线菌影响小于细菌,14d后开始恢复;百菌清对真菌影响不明显。百菌清处理后对土壤酸性磷酸酶、碱性磷酸酶、脲酶均产生一定的抑制作用,但这种抑制作用只是暂时的,随着时间的延续逐渐恢复;蔗糖酶对低浓度百菌清表现出一定的抗性;百菌清对过氧化氢酶的影响与其他酶不同,表现出先抑制后刺激的作用。

Effects of Chlorothalonil on Soil Microbial Populations and Enzyme Activities

The effect of chlorothalonil on soil microbial populations and enzyme activities was investigated in a microcosm mimicing soil ecosystem. The results showed that the bacteria were inhibited significantly after the application of chlorothalonil, and then recovered at 21d; the effect of chlorothalonil on actinomycetes in soil was less than on bacteria, and the populations of actinomycetes recovered after 14d; however, no significant inhibition of fungi caused by the fungicide was observed. The activities of acid phosphatase, alkaline phosphatase and urease in soil treated with chlorothalonil were all inhibited in the first intervals of chlorothalonil treatments.and subsequently recovered to the similar levels of the controls without chlorothalonil. Invertase was resistant to chlorothalonil at the low concentrations. The impact of chlorothalonil on catalase differed from the above soil enzymes. The activities of catalase in soil treated with chlorothalonil was inhibited in first stages of the treatment and enhanced subsequently.