Screening And Controlling Efficacy Of Antagonistic Trichoderma To Tomato Leaf Mold In Xinjiang

Tomato leaf mold is one of the plant diseases that world-wide distribution. It caused by Fulvia fulva (attach to Hyphomycetes,Passalora Fries).Such disease not only threats the production of tomatoes in the green house, but also produces the production and affects the quality of tomatoes seriously. It’s mainly relying on chemical control for controlling this disease, Currently. But, long-terms of using chemical pesticides would bring great harm to the ecological environment and resistance problems. Therefore, It becomes the hotspot to research and develop new biological pesticides.Biocontrol trichoderma and its metabolites showed strong antagonism to a variety of pathogenic fungi. This article aimed at tomato leaf mold; select the high efficiency biocontrol Trichoderma strains for the tomato leaf mold inhibition, to isolate the Trichoderma from soil and leaves surface, compare the impact of the most commonly used fungicide:arbendazim, mancozeb,speed antidotes and metalaxyl to the Trichoderma strains; carry out the investigation of the drug resistant Trichoderma bacteria and methyl thiophanate control of tomato leaf mold synergy-together. Use tomato as the host plant and tomato fulva as the indicator strain, the common thiophanate methyl as the testing agent; we studied their indoor antibacterial properties and in vivo anti-synergy effect at different concentrations. The results show as follows:1. Selecting strains of Trichoderma TCYF4 has significant inhibition to the tomato leaf mold, spore suspension of 4.553 × 106 spores/mL, the percentage of mycelial growth inhibition is 67%, and its inhibitory effect was a positive correlation between the spore concentration and effect time.2. Thiophanate-methyl, carbendazim, mancozeb, procymidone, metalaxyl and other common pesticides has certain Inhibition on Trichoderma’s growth, thiophanate methyl treating of Trichoderma has the greatest impact, and the impact of mancozeb on Trichoderma is the fairly limited. The order of spraying pesticides has certain influence on the growth of Trichoderma.3. At 25℃,The thiophanate-methyl has the inhibitory effect on the strain spore of Trichoderma TCYF4-1, and the higher the concentration, the stronger the inhibition rate.Trichoderma highly sensitive to thiophanate-methyl fungicide. There was absolutely no growth on determined strains when the concentration was 800 ug/mL.Considering the comprehensive evaluation based on the drug concentration and the inhibition rate, we suggest to keep the concentration of thiophanate-methyl below 317 μg/mL because of the obvious inhibitory effect of Thiophanate-methyl on the strain spore of Trichoderma TCYF4-1 in the low-concentration limit. The Trichoderma is sensitive to the Thiophanate-methyl fungicide, and the test shows that the strain spore does not grow at all. The synergy test in laboratory shows that collaborative using the Trichoderma TCYF4-1 and the wettable powder of 70% Thiophanate-methyl significantly increases antibacterial effect the antibacterial effect of the Trichoderma. The test of cooperatively preventing the leaf mold via using the drug-resistant Trichoderma and Thiophanate-methyl concludes that the effect of controlling the Cladosporium fulvum by using the 1000-time compound of 90% Trichoderma TCYF4-1 (1×108 CFU/g) and 10% of 70% Thiophanate-methyl shows the better-performing.