EVALUATION OF TRICHODERMA ISOLATES FOR BIOLOGICAL CONTROL OF WHEAT FUSARIUM FOOT AND ROOT ROT

Trichoderma harzianum strains 22, 35, 43, 122, and T. virens 63 and 85 were evaluated as potential biological agents for control of wheat Fusarium root rot caused by F. graminearum. Mycelial growth of F. graminearum B-63 was reduced by cell free and volatile metabolites of Trichoderma harzianum and T. viride strains by 23.12 to 43.22%. Trichoderma harzianum strain 43 significantly (P≤0.05) reduced the incidence (7.66%) and severity (3%) of disease, 42 days after inoculation and increased the 1000 grain weight in greenhouse conditions by 64% over the Fusarium inoculated control, almost at the level of non inoculated control. For confirmation of the greenhouse tests, the selected antagonists were re-examined in field trials. The Trichoderma harzianum strain 43 also reduced the disease incidence (10%) and severity (4.42%), and increased the yield of wheat in field conditions at more than double compared with the Fusarium inoculated control and at the level of non inoculated control (3.85 vs. 1.69 and 3.88 t ha -1 respectively).