Production and Testing of Biopesticide for Control of Postharvest Mold Infections on Fresh Fruits of Apple and Pear

Abstract

The present research aimed at producing a biopesticide with proper formulation of invert emulsion (water-in-oil type) and effective strain of Trichoderma harzianum then, testing it against pathogens of postharvest mold infections ( Botrytis cinerea & Penicillium expansum ) on fresh fruits of apple and pear. The proper formulation of invert emulsion (IE#3) used for biopesticide production has the following ingredients (100% w/w): soybean oil (28.50%), coconut oil (19.50%), oil-soluble emulsifier: Tween 20 (2.0%), glycerine (4.25%), water-soluble emulsifier: dehymuls k (0.75%) , sterile distilled water (22.5%) and conidial suspension of the effective strain of T. harzianum “TrichoPAL1” in water (22.5%, concentration 1 × 10 7 conidia/ml ). Testing efficacy of the produced biopesticide has indicated a significant reduction in the disease lesion diameter of mold infections on wounded apple and pear fruits stored at 20 ℃ ± 1 ℃ compared to the untreated fruits or control (reduction from up to 38.75 to about 7.50 mm, respectively, according to the type of mold infections and fruit type ). Also, the treatment with the produced biopesticide has resulted in a long protection period from mold infections on wounded and un-wounded fresh fruits of apple and pear stored under controlled and semi-commercial conditions (up to 2.5 months according to the type of mold infections and fruit type). In conclusion, the overall results have demonstrated the effectiveness of produced biopesticide on stored fruits under controlled and semi-commercial conditions therefore, it is recommended to test this effectiveness on marketed fruits stored under variable conditions before applying it at a large scale.