Study On Biocontrol Mechanism Of Trichoderma Viride On Rhizoctonia And Trichoderma Preparation

Antagonistic mechanism of isolate TCS-1 of Trichoderma viride onRhizoctonia and effect of TCS-1 on wheat were screened in the paper. On thebase of research on mechanism of competition,hyperparasitism and antibioticaction, the experiment was further carried out in zymin level.ExtracellularPolygalacturonase(PG) activities of Rhizoctonia and higher inhibition on PGactivities by extracellular metabolite of isolate TCS-1 were testified. Effects ofTCS-1 on defense enzymes,chlorophyl content and growth of wheat wereinvestigated. The fermentation conditions were further optimized by orthogonaldesign.Isolate TCS-1 was screened from eight isolates by testing and comparingtheir antibiotic action through the antagonistic culture with three isolates ofAG-D of Rhizoctonia cerealis and one isolate of AG1-IA of R.solani. It wastestified that extracellular metabolite of TCS-1 had obviously agonistic effecton Rhizoctonia, which vared as the producing time of extracellular metabolite,TCS-1 belongs to Trichoderma viride by identification. The very fermentationcondition of TCS-1 was brown sugar as carbon sources , ammonium sulfate asnitrogen, bitter salt as inorganic salt, 4/6 as ratio of carbon and nitrogen,5 as pH,27.5℃as temperature,6 days as culture time.TCS-1 can accelerate the growth of wheat in the condition of illuminationincubator and greenhouse, height and weight of wheat both increased than thecomparison, and the colour of leaf of wheat treated with TCS-1 intensified, andthe main root of wheat treated with TCS-1 became thickset, the lateral rootsbecame more and stronger. Otherwise TCS-1 also can obviously improve thechlorophyl content of wheat.Effects of TCS-1 on defense enzymes of wheat were investigated. Themensuration of enzymes activities showed the fermented broth of TCS-1 with...