Production and application of Trichoderma harzianum Tr6 for control of damping-off caused by Phytophthora drechsleri and growth promotion on cucumber

Trichoderma is one of the important biocontrol agents for certain plant disease that control with different mechanisms. This fungus similar to other biocontrol agents is under the influence environmently factors. Medium is one of these factors. This study was investigated effect of the medium (Mol.C.B.M.) containing Sugar beet molasses, Corn steep liquor, Baker’s yeast and Malt extract as the liquid medium and two solid media including: Wheat bran (W.b.) and Wheat seed (W.s.) on sporulation, biocontrol efficacy of Trichoderma harzianum Tr6 against Phytophthora drechsleri and growth promotion of the plant. The media were inoculated with 1ml of suspension containing 108 spores of the antagonist and were maintained in an incubator a light intensity of 206 Lux and at 28°C for 10 days. The medium Mol.C.B.M. of biomass had the most effect on sporulation (1.83×1010 spore/gdw), disease control (62.5%), height, fresh and dry weight of shoots and roots of the plant. But percentage inhibition was lesser than solid media at laboratory surveys.Therefore, the medium Mol.C.B.M. was efficient to encompass the objectives of this study.