Submitted to: Postharvest Biology and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 10, 2007
Publication Date: September 1, 2007
Citation: Conway, W.S., Janisiewicz, W.J., Leverentz, B., Saftner, R.A., Camp, M.J. 2007. Control of blue mold of apple by combining controlled atmosphere, antagonist mixtures and sodium bicarbonate. Postharvest Biology and Technology. 45:326-332.
Interpretive Summary: It is imperative to find alternatives to chemical control to reduce losses due to postharvest decays. There has been an increasing demand by consumers to reduce residues on produce due to health and environmental concerns and many fungi are becoming resistant to commonly used fungicides. Alternatives to chemical control, when used alone, are usually not as effective as fungicides. To increase effectiveness, we combined three alternative control methods: biological control using two yeasts alone or in a mixture, sodium bicarbonate solutions, and controlled atmosphere storage. When combined, these treatments resulted in better control of blue mold decay of apple than any of the treatments used alone. The apple industry may find that integrating biological control, sodium bicarbonate solutions, and controlled atmosphere storage may be a useful alternative to postharvest decay control using fungicides.
'Golden Delicious' apples were wound-inoculated with Penicillium expansum, treated with various combinations of sodium bicarbonate and two antagonists, and stored in air or controlled atmosphere (1.4% O2, 3% CO2). The fruit were stored for 2 or 4 months at 1°C. The antagonists survived and their populations increased in both air and controlled atmosphere storage (CA). The antagonists alone reduced decay but tended to be somewhat more effective when combined. Sodium bicarbonate tended to reduce lesion size when used with each antagonist alone or combined. Storage under CA conditions also increased the effectiveness of each antagonist, alone or in combination. The only treatment that completely eliminated decay caused by this pathogen was the combination of the two antagonists and sodium bicarbonate on fruit stored under CA conditions. The proper combination of alternative control measures could help reduce our dependency on fungicides.