Development Of Antagonist Compound Bacterium Bungicide On Main Oil-tea Camellia Diseases

As a new 'green pesticide',microbial pesticide has gradually replaced old pesticides for its high quality,low toxicity and vestigital,and eco-friendliness.Actinomycetes,distributed abroad in nature,could produce many effective metabolic and control plant diseases caused by fungus,which is an significant resource of microbial pesticides.Bacteria are the main microbial group applied to produce microbial pesticide,which is also widely used with good effect.Strain CF17 was identified as the streptomyces albulus,separated and filtered from the actinomycetes of rhizosphere soil in Hunan oil-tea camellia base,which exerts good antagonism effect on main disease of oil-tea camellia.Strain Z26 was also filtered from that soil and identified as the bacillus brevis.CF17 and strain Z26,which have good antagonism effect on oil-tea camellia disease,were used as materials to investigate its fermentation technology of compound bacteria,antibacterial spectrum and stability,and complex microbial inoculants.The main results are as follows:1.Investigation on fermentation condition optimization of the actinomycetes CF17 and its compound bacterium:Since actinomycetes CF17 and bacteria Z26 have good antagonism effect on a variety of camellia diseases,the influence of the biological activity of composite probiotic fermented liquid caused by different nutrition factors,such as fermentation culture medium and carbon nitrogen source,and non-nutritional factors,such as incubation time,inoculation quantity,liquid volume,initial pH,combined incubation time,proportion of vaccination and inoculation interval time are researched with dry weight of fermented liquid bacteria and the antibacterial rate as main measures for developing and utilizing them.The results show that optimization fermentation broth of the compound bacteria consists of 15 g glucose,10 g soy flour,1 g NaC15g,1 g yeast extract,1 g CaC031g,1000 ml distilled water,pH7.0,10%inoculation amount,100 ml for liquid loading capacity,1:3 as inoculation proportion,5 days for inoculation interval time,28?,and oscillation 7 d with 160 r/min.2.Research on compound bacterium antibacterial spectrum and antibacterial stability of fermented liquid.Since actinomycetes CF17 and bacteria Z26 have good antibacterial effect on main oil-tea diseases,the cross crossover method and drilling method were adopted.The results showed that the compound bacteria had a strong antibacterial effect on camellia blight bacteria,colletotrichum camelliae mass,Oiltea camellia root rot fungus,and cunninghamia lanceolata anthrax bacteria.The antibacterial rate can reach more than 90%.It also have good bacteriostatic effect(bacteriostatic rate 83.57%)on soft rot of oiltea camellia.However,it didn't show antibacterial effect on walnut shell shuttle spore bacteria and chestnut branch blight pathogen.After composite probiotic fermented liquid was treated with different acid and alkali,heat and UV radiation,the results showed that compound fermented is not stable under acid alkali and ultraviolet irradiation condition,and with poor thermal stability.3.Production of Compound bacterium fungicide.According to the biological characteristics of antinomies CF17 and bacteria Z26,the composite fermented liquid was used to make water dispersible granule.After determination of biocompatibility,diatomite,wetting agent sodium dodecyl sulfate(SDS),sodium lignin sulfonate dispersant,STPP,sodium tripolyphosphate,adhesive polyvinyl alcohol,polyethylene glycol,soluble starch,disintegrating calcium chloride,ammonium sulfate and sodium chloride were preliminary screened.Since having little influence on bacteriostatic activity and colony growth of composite strain,they were used in the next step.With wetting,dispersion,suspension,disintegrating time as the main measures,by means of wetting agent,dispersant,binder,disintegrating agent and other additives screening,the composition and content of water dispersible granule of the compound bacteria were finally comfirmed:raw powder 40%,wetting agent sodium dodecyl sulfate 4%,dispersant sodium lignin sulfonate 5%,disintegrating agent ammonium sulphate 4%,binder polyethylene glycol(peg)2%,water addition between 16-20%,carrier kaolin 100%as complement.Pot experiment and the control effect test indicated that the compound bacteria fungicide had good treatment effect and prevention effect on the blight bacterium of oil tea.500 times of compound bacteria fungicide had good prevention effect on diluent(over 80%),which was superior to carbendazim on control efficiency,and can effectively promote the growth of camellia seedlings.