二甲基二硫熏蒸对保护地连作土壤微生物群落的影响  

Effects of dimethyl disulfide on microbial communities in protectorate soils under continuous cropping

作　　者：王方艳[1] 王秋霞[1] 颜冬冬[1] 毛连纲[1] 郭美霞[1] 燕平梅[1] 曹坳程[1] 

机构地区：[1]中国农业科学院植物保护研究所,北京100193

出　　处：《中国生态农业学报》2011年第4期890-896,共7页Chinese Journal of Eco-Agriculture

基　　金：国家自然科学基金项目(40871131);现代农业产业技术体系北京市创新团队基金项目资助

摘　　要：随着保护地高附加值经济作物的连年栽培,土传病害问题愈发突出,熏蒸剂也因此得以更广泛的应用。但鉴于熏蒸剂的广谱性,在杀死有害生物的同时,不可避免地对非靶标生物产生一定的影响。为明确溴甲烷替代药剂二甲基二硫(dimethyl disulfide,简称DMDS)熏蒸对土壤微生物群落的影响,本研究在室内条件下采用BIOLOG方法,测定不同浓度DMDS熏蒸对保护地连作土壤微生物群落的影响。研究结果表明:不同浓度DMDS(170.00 mg.kg-1、85.20 mg.kg-1、42.50 mg.kg-1、21.30 mg.kg-1和10.62 mg.kg-1)熏蒸处理对镰孢菌属(Fusarium spp.)和疫霉菌属(Phytophthora spp.)的LC50(抑制中浓度)分别为42.08 mg.kg-1和115.15 mg.kg-1。DMDS熏蒸后恢复培养0 d取样,温育120 h时,170.00 mg.kg-1、42.50 mg.kg-1和10.62 mg.kg-1的DMDS处理土壤的AWCD值(平均每孔颜色变化率,average well-color development,AWCD)分别比空白对照升高8.46%、6.02%、19.31%,表明DMDS促进了土壤微生物的生长。恢复培养14 d后,各处理土壤微生物的AWCD值恢复至对照水平。多样性指数分析显示,DMDS熏蒸后恢复培养0 d时,土壤微生物群落的Shannon指数、Simpson指数均高于空白对照,McIntosh指数与对照无显著性差异;恢复培养7 d后,Shannon指数与Simpson指数恢复至对照水平。主成分分析结果显示,DMDS熏蒸后恢复培养0 d时,各处理间微生物对碳源的利用方式差异显著,恢复培养14 d后,DMDS对微生物碳源利用方式的影响逐渐减弱,恢复至对照水平。结果表明,DMDS熏蒸处理对土壤微生物的生长具有促进作用,影响了微生物对碳源的利用方式,但在恢复培养14 d后,被干扰的土壤微生物逐渐恢复至对照水平。DMDS熏蒸处理在有效防控土传病原真菌的同时,不会对土壤微生物群落产生明显的扰动影响,对环境较安全。Soil fumigants are widely used to protect agricultural and high-value cash crops from soil-borne diseases.As broad-spectrum agents,however,fumigants also have side effects on non-target organisms.Dimethyl disulfide（DMDS） is a new alternative to methyl bromide（MeBr） that reduces plant fungal pathogens and nematodes.DMDS is therefore recommended by the Methyl Bromide Technical Options Committee of the United Nations Environment Program（UNEP）.This study was an attempt to identify the effects of DMDS on microbial communities in protectorate soils under continuous cropping.The efficacy of DMDS was evaluated by bio-assay in the laboratory.The efficacy of DMDS on the Fusarium spp.and Phytophthora spp.was observed after fumigations.The LC50 of DMDS with different concentrations（170.00 mg·kg 1,85.20 mg·kg 1,42.50 mg·kg 1,21.30 mg·kg 1 and 10.62 mg·kg 1） was 42.08 mg·kg 1 and 115.15 mg·kg 1,respectively to Fusarium spp.and Phytophthora spp.Microbial community structures after DMDS fumigation were evaluated using BIOLOG Ecoplates under laboratory conditions.Compared with the un-treated/control plants,the average well color development（AWCD） of the DMDS 10.62 mg·kg 1,42.50 mg·kg 1 and 170.00 mg·kg 1 respectively increased by 8.46%,6.02% and 19.31%,0 day after fumigation and 120 h after sample incubation.AWCD increased by 1.87%,3.47% and 8.01%,respectively,240 h after incubation;which indicated that DMDS promoted the growth of microbes.AWCD of treated samples were close to the control at 14 days after fumigation.The indices of Shannon and Simpson at 0 day after fumigation were higher than that of the control,recovering to the levels of the control 7 days after fumigation.Based on McIntosh index,there was no significant difference between the fumigation treatments and the control.Principal component analysis of sub-strate reaction reflected that the use of carbon sources by microbial community was obviously different in the treatments immediately after fumigation.It was,however,close to the contro

关 键 词：二甲基二硫 土壤微生物群落 镰孢菌属 疫霉菌属 BIOLOG方法 Shannon指数 Simpson指数 McIntosh指数 AWCD值 

分 类 号：S154.3[农业科学—土壤学]