乙草胺的微生物降解及其对土壤磷脂脂肪酸特性的影响  

Microbial degradation of acetochlor in mollisol and the effects of acetochlor on the characteristics of soil phospholipid fatty acids

作　　者：冯慧敏[1] 何红波[1] 白震[1] 武叶叶[1] 郭柏栋[1] 张明[2] 张旭东[1] 

机构地区：[1]中国科学院沈阳应用生态研究所 [2]辽宁大学,沈阳110036

出　　处：《应用生态学报》2008年第7期1585-1590,共6页Chinese Journal of Applied Ecology

基　　金：国家重点基础研究发展规划项目(2005CB121104);中国科学院沈阳应用生态研究所创新领域前沿资助项目(SLYQY0602)

摘　　要：通过监测不同培养条件下(灭菌、加选择抑菌剂、未灭菌)土壤中乙草胺残留数量和培养期间微生物标识物磷脂脂肪酸(PLFAs)含量的变化,探讨了以田间推荐量施用乙草胺时,不同微生物群落对乙草胺降解的相对贡献以及乙草胺对黑土微生物群落结构的影响.结果表明:乙草胺易于被微生物降解,其中,细菌对乙草胺的降解作用显著大于真菌,而真菌对乙草胺有更强的耐受能力.施入乙草胺后,各磷脂脂肪酸数量发生了显著变化,C14∶0、C16∶0和C18∶0所指示的土壤微生物量均有所下降;细菌PLFAs数量在培养初期显著降低,而后与对照的差异显著减小,表明细菌活性随着乙草胺的降解有所恢复;在施用乙草胺后的整个培养过程中,土壤真菌PLFAs数量始终低于对照,暗示着乙草胺对真菌的抑制可能是长期而不可逆的.An incubation test was conducted with mollisol applied with recommended amount of acetochlor under the conditions of sterilization,microbial inhibitor addition,and non-sterilization.During incubation,the residual amount of acetochlor and the dynamics of soil phospholipid fatty acids（PLFAs）were determined to study the relative contribution of soil microbes on the degradation of applied acetochlor,and the effects of acetochlor on the soil microbial community structure.The results showed that acetochlor was easy to be degraded by soil microbes,and bacteria contributed more than fungi.After applying acetochlor,the contents of various PLFAs changed evidently,and the soil microbial biomass indicated by C14∶0,C16∶0 and C18∶0 was decreased.The bacterial PLFAs decreased significantly at the beginning of the incubation,but had less difference with CK（no acetochlor application）later,suggesting that bacterial activity was restored along with the degradation of acetochlor.The content of fungal PLFAs in the soil samples applied with acetochlor was lower than that of CK,implying that the inhibition of the herbicide to fungi was chronic and irreversible.

关 键 词：乙草胺 降解 磷脂脂肪酸 微生物群落 真菌 细菌 黑土 

分 类 号：S154.3[农业科学—土壤学]