放线菌菌株HJG-5生防剂型的研制及对黄瓜枯萎病的防治效果

Preparation of Biocontrol Agent of Actinomycetes Strain HJG-5 and Its Control Effect on Cucumber Fusarium Wilt

放线菌HJG-5是一株对多种植物病原真菌具有较强抑制作用的肉桂栗色链霉菌(Streptomyces cinnamocastaneus)。通过单因素分析与正交组合试验,筛选其固体发酵基质,优化发酵条件,研制了两种不同的剂型,并测定菌剂对黄瓜枯萎病的防治效果。结果表明,菌株HJG-5最适固态发酵基质为大米粉,固态发酵优化配方为:麦芽糖(碳源)50 mg/g,胰蛋白胨(氮源)50 mg/g,接种量0.8 mL/g,培养时间120 h,pH 7.5;菌剂的助剂优化配比为:高岭土(载体)100 mg/g,羧甲基纤维素钠(分散剂)20 mg/g,海藻酸钠(保护剂)20 mg/g,研制出粉剂和颗粒剂两种剂型。盆栽防治试验显示,施用7 d和14 d后,粉剂和颗粒剂对黄瓜枯萎病的防效达60%以上;施用28 d后,两种剂型对病害的防效达50%以上,显著高于50%多菌灵可湿性粉剂,但又显著低于10%苯醚甲环唑水分散粒剂。放线菌菌株HJG-5生防剂型对黄瓜枯萎病具有较好的防治效果及进一步开发利用价值。

Endophytic actinomycete strain HJG-5 is Streptomyces cinnamocastaneus that has strong stability and good inhibitory effect on various pathogens.The solid fermentation matrix of strain HJG-5 was screened out,fermentation conditions was optimized and two kinds of formulation were prepared by one-way analysis of variance(ANOVA)and orthogonal combination test,and then the control effect on cucumber Fusarium wilt was determined.The results showed that the optimum solid-state fermentation matrix for strain HJG-5 was rice flour,the final optimized formula of solid-state fermentation was as follows:maltose(carbon source)50 mg/g,tryptone(nitrogen source)50 mg/g,inoculation amount 0.8 mL/g,culture time 120 h and pH value 7.5,the optimum formula of adjuvant was as follows:Kaolin(carrier)100 mg/g,sodium carboxymethyl cellulose(protecting agent)20 mg/g and sodium alginate(dispersing agent)20 mg/g based on solid-state fermentation,finally,so the formulations of powder and granule were prepared.The control effect of powder and granule on cucumber Fusarium wilt in the pot experiment was more than 60%on the 7th and 14th day,and more than 50%on the 28th day.The effects were higher than that of 50%carbendazim WP and significantly lower than that of 10%phenylethoxazole WDG.In conclusion,the biocontrol agent of actinomycetes strain HJG-5 has an better control effect on cucumber Fusarium wilt,which is worth further being developed and utilized.