土壤和叶际微生物对啶虫脒的降解作用

深入研究了土壤、叶际原位和叶际可培养微生物对啶虫脒的降解作用及各条件下降解效果的差异.结果表明,不同环境下的微生物对啶虫脒有不同程度的降解效果.原位叶际微生物对啶虫脒降解影响的程度较小,在灭菌处理与对照叶面中啶虫脒的半衰期分别为8 1 d和6 6d.相对而言,土壤和叶际分离培养微生物对啶虫脒降解作用更加显著,在自然土壤和灭菌土壤中啶虫脒的降解半衰期分别为5.0 d和39.6d,相差为8倍;和原位叶际微生物相比,在油菜叶培养基中微生物的生物量大幅度提高,同时,对啶虫脒的降解效果也更加显著;在灭菌处理的豆叶培养基中(CK),啶虫脒42d的降解率为16.5%,相同时间内非灭菌处理的叶际分离微生物降解率高达95%,其降解速率与培养基中的微生物量呈正相关性,叶际和土壤中都存在能降解啶虫脒的微生物.

Acetamiprid degradation by microbes of the soil and phyllosphere

Acetamiprid is chloronicotinoid insecticides,its degradation by microorganisms under different conditions of laboratory reared soil,in situ phyllosphere,and mixed microbial culture from the phyllosphere was investigated.Microbes of the phyllosphere in situ were less effective in degrading acetamiprid than the other treatments.The half-lives were 8.1 d in sterilized and and 6.6 d in unsterilized treatments.Acetamiprid could be degraded more quickly by microbes from soil and mixed microbial enrichment culture from the phyllosphere.The half-life of acetamiprid was 5.0 d in unsterilized soil,8 times faster than in sterilized soil(half life = 39.6 d).Compared to the in situ phyllosphere,mixed microbial culture from the phyllosphere had increased microbial mass,and showed a more rapid acetamiprid degradation with a degradation rate of 95% over 42 d,while in the sterilized control treatment only 16.5% acetamiprid could be eliminated.The degradation rate correlated positively with microbial mass in phyllosphere enrichment media,which is evidence for the existence of acetamiprid degrading microorganisms in both the phyllosphere and in soil.