中文摘要：

从生长健康的药菊根际土壤分离筛选获得一株对其连作土传枯萎病致病菌（尖孢镰刀菌菊专化型）具有较强拮抗作用的细菌a4,并通过盆钵和田间小区试验研究其生防效果。结果表明,拮抗菌a4对药菊枯萎病病原菌的抑制率达71%。盆栽试验中,施用a4二次发酵的生物有机肥（CK＋BOF1）,未发生药菊枯萎病,而对照植株则完全发病;对照植株根际土壤尖孢镰刀菌的数量为CK＋BOF1处理的6.5倍。田间小区试验,苗床育苗和移栽时都施用BOF并加灌a4发酵液的处理（n＋F＋a4）,根际土和非根际土中病原菌的数量分别为2.0×103和2.8×103cfu/g,而对照则分别为1.4×104和1.2×104cfu/g。n＋F＋a4处理生长120 d的药菊生物量（干重）为对照的4.47倍,生防效果达93.2%。采用苗床育苗和移栽时都施用高效拮抗菌的方法,能有效防止枯萎病发生,促进药菊植株生长,提高产量。

英文摘要：

In this experiment,one of antagonistic bacteria named a4 was isolated from the soil which collected from the rhizosphere of regular growing medicinal chrysanthemum,its resistance against the pathogen（Fusarium oxysporum f.sp.Chrysanthemi） was screened respectively by the improved confront culture method,and its biocontrol effect on the medicinal chrysanthemum fusarium wilt was examined by the pot experiment and the field plot trials.Results showed： 1）The inhibition rate of a4 against the pathogen was 71%.2） In the pot experiment,the wilt disease incidence of the treatment adding a4（CK＋BOF1） was 0% compared to 100% in control.The number of the pathogen in rhizosphere soil of control was 6.5 fold higher than that of CK＋BOF1.3） In the field trial,the number of the pathogen was 2×103 cfu/g in rhizosphere soil and 2.8 ×103 cfu/g in the bulk soil in the treatment of（n＋F＋a4）,which were applied BOF in nursery soil and added antagonistic bacterial a4 into transplanted soil,it was significantly lower than control（1.4×104 cfu/g in rhizoplane soil and 1.2×104 cfu/g in the bulk soil）.4） Biomass of medicinal chrysanthemum was significantly increased in the treatment of n＋F＋a4 comparing with control,the root biomass increased 92%（fresh weight） and 84%（dry weight）;while the fresh weight of shoot increased 77% and dry weight increased 69%.During 120 day experiment period,the control efficiency of n＋F＋a4 on medicinal chrysanthemum fusarium wilt was 93.2%.and the biomass with it was 24.5 g/plant（DW）,was significantly higher than that of control（5.46 g/plant,DW）.Results suggested that applying BOF both in nursery and transplanting can effectively prevent the occurrence of medicinal chrysanthemum fusarium wilt disease,promote the growth of medicinal chrysanthemum plant,and increase its yields,thus easing continuous monocropping obstacles.