乙草胺、甲胺磷及其复合对土壤真菌种群的毒性效应  

Toxic Effects of Acetochlor, Methamidophos and Their Combinations on Soil Fungi

作　　者：李新宇[1] 张惠文[1] 吴敏娜[1] 张勤[1] 张成刚[1] 

机构地区：[1]中国科学院沈阳应用生态研究所,辽宁沈阳110016

出　　处：《农业环境科学学报》2008年第5期1842-1847,共6页Journal of Agro-Environment Science

基　　金：国家基础研究项目(2004CB418503);沈阳应用生态研究所博士启动基金(C17DC06SBS31001)

摘　　要：农药的施用会对土壤非靶向微生物的数量、种群结构产生影响,目前关于这方面的研究主要集中在土壤细菌,而真菌的较少。以从中科院海伦生态站采集的农田黑土作为实验土壤,采用室内模拟和PCR-DGGE(变性梯度凝胶电泳)的方法,考察北方常用的除草剂乙草胺和杀虫剂甲胺磷对真菌多样性和种群结构的影响。设定对照,乙草胺3个浓度单独处理(50、150、250mg·kg-1),甲胺磷3个浓度单独处理(50、150、250mg·kg-1)和它们复合的9个处理,共16个处理。结果表明,乙草胺单独作用时,增加了土壤真菌的多样性,并且对真菌多样性和种群结构的影响在第1周尤为显著,处理8周后呈恢复的趋势。甲胺磷单独作用时对土壤真菌多样性起抑制作用,使真菌种群结构发生了改变,随着培养时间的延长,其对真菌影响也逐渐减弱,真菌种群多样性和结构在处理8周后可部分恢复。乙草胺与甲胺磷相复合时,土壤真菌多样性的变化因两种农药浓度组合的不同而不同。在培养初期多数复合处理降低了土壤真菌的多样性,至末期时多数处理可增加真菌的多样性。对种群结构的影响在第1周时,中、高浓度甲胺磷与乙草胺的复合以甲胺磷为主导因子,第8周时乙草胺与低、中浓度甲胺磷复合时起到主导作用,经8周培养后,各复合处理土壤真菌种群结构并未恢复到对照水平,复合处理比单因子的生态效应要强,作用方式更复杂。Pesticide application has negative effects on the diversity and population structure of non-target soil microbes. Many studies have been made on the effects of pesticides on soil bacteria, but less on soil fungi. With the farmland black soil at Hailun Ecological Experimental Station under Chinese Academy of Sciences in Heilongjiang Province of Northeast China as test object, a laboratory incubation test was conducted to investigate the effects of acetochlor and methamidophos, the commonly used pesticides in North China, on the diversity and population structure of soil fungi. 16 treatments were installed, i.e., 3 concentrations （50, 150 and 250 mg·kg^-1） of acetochlor, 3 concentrations （50, 150 and 250 mg·kg^-1） of methamidophos, 9 combinations of each concentration of acetochlor and methamidophos, and CK, and soil samples were taken at a 7 day- interval during the incubation for PCR-DGGE analysis. The results showed that acetochlor increased the diversity of soil fungi, and its effects on the fungal diversity and population structure were most obvious in the 1^st week of incubation but less remarkable after 8 weeks. Methamidophos decreased the diversity and altered the population structure, but the effects were weakened with time, and a partial recovery of the diversity and population structure was observed after 8 weeks. As for the combinations of acetochlor and methamidophos, most of them decreased the fungal diversity in the early period of incubation but increased it by the end of the incubation. The effects also differed with the concentrations of the two pesticides in the combinations. In the 1^st week of incubation, medium and high concentration methamidophos in their combinations with acetochlor played dominant role; while in the 8^th week, acetochlor in its combinations with low and medium concentration methamidophos was the leading factor. After 8 weeks incubation, the population structure of soil fungi under the effects of the combinations of acetochlor and methamidophos was still not restor

关 键 词：变性梯度凝胶电泳 土壤真菌 复合污染 乙草胺 甲胺磷 

分 类 号：X592[环境科学与工程—环境工程]