Condition For Producing Xylanase And Induced Resisitance In Rice By Biocontrol Agent Trichoderma Strains

The induction of resistance in plants by Trichoderma spp as biocontrol agents has been poorly studied compared with rhizo-bacteria. In this work, four Trichoderma strains were used to research the condition for producing xylanase in laboratory, and the induced resistance of rice (Oryza sativa L. ) to Rhizoctonia solani by conidial suspension and crude xylanase of Trichoderma NF₉ was observed.The results obtained are as follows:1. The optimal condition for producing xylanase in laboratory: for strain NF9 : initial pH 5.0, 30℃, 72h;for strainP₁ : pH 4.0, 27℃, 84h;for strain CT₂₂ : pH 5.0, 27℃, 84h;for strain TC₃ : pH 4.0, 30℃, 96h. Among the four Trichoderma strains tested NF₉ was the best one for producing xylanase.2. The induced resistance of rice to Rhizoctonia solani by conidial suspension of and by crude xylanase of Trichoderma NF₉ was observed.3. Trough the methods of fluorescence quantify RT-PCR, the chitinase gene Rcht2 overexpression in rice plants induced by conidial suspension and crude xylanase of Trichoderma NF₉ was detected.