Development Of The Biocontrol Agents Of FO47

Non-pathogenic Fusarium oxysporum FO47 was screened out of the soil, its mainly mechanism was competition and induction. Biocontrol agent FO47 could be used to prevent soil-borne diseases which were caused by the Fusarium oxysporum and Fusarium moniliforme, at the same time, it also had an effect on cucumber downy mildew. In this study, we used liquid and solid two-phase fermentation process, optimized solid-state fermentation of biocontrol agent FO47, and screened out the carriers, which had improved the containing condition of FO47.As a consequence, we developed it into granules and then measured its growth-promoting effect and disease prevention . Meanwhile, we continued our experiment to tirtura more complex combinations with biocontrol agents to test their synergistic function, providing the theoretical basis for the development of biocontrol agent FO47.1,With LgCFU as an indicator, we used orthogonal design L16 (45) test to optimize the solid-state fermentation of biocontrol agent FO47. The optimum medium for solid-state fermentation is: wheat bran 83%, the corn flour 17%, sugar 2.9%, peptone 7%, cottonseed skin 4%, pH 6.0, initial moisture content 60%, the seed age 96h, inoculum 20%. Using the optimized regimen solid culture, we significantly increased the number of the biocontrol agent.2,Using Petri dish culture experiments, we carried out the process of screening the solid support of FO47, and we selected non-cultivated loess, chitosan, diatomite and so on. Then we carried our research to the heat treatment of five carriers and gradually filter out the most suitable carrier. The optimal vector of biocontrol FO47 identified as kaolin, chitosan and chitin. After that, we mixed the three carrier with biocontrol FO47 according to certain proportion, measured at different temperatures and different times. As a result, kaolin is the best strain of storage at 4℃. The three carriers had the role of UV protection, and the best protective effect is kaolin .3,Using the three carriers of the granules, we developed FO47 1, 2, 3, testing its prevention of Fusarium Wilt of Watermelon. And their disease control effects of FO47 1, 2, 3 were 42.22%, 73.42% and 71.53% respectively. They were all better than FO47 powder effect. 4,Also, we tested the growth condition of F104 in the bran, slag and other kinds of mushrooms, and further selected the most suitable substrate: wheat bran + corn flour (5:3), the initial moisture content was 70% and inoculums was 30 %.5,We combined the biocontrol agent actinomycete F104 and non-pathogenic Fusarium oxysporum FO47 to form a complex agent, measured its promoting effect on seedling growth. The result was better than the effect of single powder. Especially, it provided a theoretical basis for further compound development of agents.