Biological Control of Rhizopus Soft Rot on Apple, Pear and Peach by Trichoderma harzianum

This research aimed at evaluation of biological effectiveness of Trichoderma harzianum against the Rhizopus soft rot caused by Rhizopus stolonifer. Also, it aimed at determination of minimum protection period from infection with Rhizopus soft rot on three types of fruits (apple, pear, and peach). The fungus was mainly applied in form of invert emulsion (water - in - oil formulation) after being introduced into the emulsion in form of conidia in addition to using formulated and non-formulated forms of the fungus. The experiments (evaluation of efficacy) was carried out under laboratory conditions (20 + 2C and 30 + 2C). Results obtained have demonstrated that the fungus (Trichoderma harzianum) formulated in invert emulsion was effective in reducing Rhizopus soft rot lesion diameter compared to other treatments. Significant differences (P?0.05) were obtained in reducing the lesion diameters of Rhizopus soft rot treated with Trichoderma in invert emulsion in comparison with the control treatment. Results have also indicated that Trichoderma formulated in invert emulsion on unwounded apple fruits gave the longest minimum protection period against Rhizopus soft rot disease, which demonstrated the biological effectiveness of Trichoderma harzianum. Moreover, it is recommended to confirm the efficacy of the fungus against R. stolonifer especially in the formulated form under a wide range of temperatures and relative humidifies, in addition to controlled atmosphere conditions and using other fungal strains of T. harzianum against R. stolonifer in the same formulation and may be other formulations can be also tested. Using other kinds of fruits also may expand the knowledge and verify the concept of biological control.