Efficacy of Non-Chemical Alternatives on Blue Mold of Apple under Controlled Cold Storage Conditions

Abstract

Fruits of three apple cultivars; Golden Delicious, Granny Smith and Fuji were inoculated with blue mold, Penicillium expansum, and kept under cold storage conditions for 75 days after treatment with non-chemical alternatives and the fungicide Topsin as a standard. This aimed at providing new postharvest methods for the control of blue mold incidence and severity in apple fruits. Granny Smith showed lower sensitivity to blue mold disease than Golden Delicious but Fuji was the most sensitive to the disease in relation to fruit firmness and total soluble solid content (TSS). Dipping apple fruits in yeast (Saccharomyces cerevisiae) solution at a concentration of 1 g L -1 or in hot water at 50 °C for 1 or 5 min., or exposing them to microwave for 10 s resulted in an effective control of blue mold disease under controlled cold storage conditions. Calcium nitrate at 1 or 8 g L -1 did not result in an effective control of blue mold but increased the storability of apple fruits. Therefore, a combination of two or more of the alternatives may provide a long-lasting effective control of post-harvest blue mold affecting apple fruits.