Study On Isolation, Identification And Biological Control Effect Of Trichoderma T43

Trichoderma is the most widely used biocontrol fungi, it can not only prevent plant disease, but also can promote plant growth. Trichoderma play a vital role in plant protection against soil-borne pathogens, improving agricultural ecosystem, keeping the plants microecosystem biodiversity and maintain sustainable development. The aim of the study is screen anti-microorganism Trichoderma for plant disease control.By the methods of mycelium growth rates screening and confront culture screening compound screening system, screening out a Trichoderma strain T43 from 34 strains Trichoderma strains, it exhibited strong antagonistic activities against Fusarium oxysporum f. sp. cucumerinum Owen, Rhizoctonia solani Kuhn and Fusarium oxysporum Schlecht., inhibitory rate reached 81%,77% and 79%. The results showed that Trichoderma T43 is a biocontrol fungi.Trichoderma T43 was identified as Trichoderma viride on the basis of the morphology and DNA sequence analysis of ITS rDNA molecular biology identification. The investigation of Trichoderma T43 biological characteristics showed that, the best hypha growth condition is PDA medium, maltose, peptone, Fe, pH=5 and 24h dark treatment, the best hypha accumulation condition is NA medium, glucose, beef extract, Mg, pH=7 and 24h light treatment.Trichoderma T43 not only have broad-spectrum control, showed antibiosis against fourteen different plant fungal pathogens, such as Fusarium oxysporum f. sp. cucumerinum Owen, Fusarium oxysporum Schlecht, Fusarium oxysporum f. sp. Vasinfectum, Fusarium graminearum, Geotrichum candidum, Vermicularia capsici Syd, Gloeosporium fructigenum, and bacteriostatic rate all above 70%, but also have high inhibitory effect, and had 88% suppressive rate to Cytospora mandshurica Miura.Trichoderma T43 can promote the germination and growth of cucumber seed and wheat seed. Trichoderma T43 has best promoting effect on the growth of cucumber root in the spores concentration of 1×105 per milliliter which was increased by 9%, and it has best promoting effect on the growth of wheat bud and root in the spores concentration of 107 per milliliter which was increased by 29% and 18%. The growth-promoting effect is different on seed by different treatment of T43 fermentation liquor. The growth-promoting effect of fermentation liquor and fermentation liquor by suction filtration show a parabolic trend, and the seed grows rate gradually increase as the concentration increase of fermentation liquor by autoclaving.The middle-pressure liquid chromatography analysis on non-volatility metabolite of Trichoderma T43 showed that Trichoderma T43 at least nine components, and each component has antibacterial effect to Fusarium oxysporum f. sp. cucumerinum Owen, component ? has best antibacterial effect and its inhibition zone reach up to 30.7 mm.