Reduction of Mycoflora and Control of In-Shell Weevils in Pecans Stored Under High Carbon Dioxide Atmospheres. John M. Wells, Plant Pathologist, Southeastern Fruit and Tree Nut Research Laboratory, USDA, SEA/AR, P.O. Box 87, Byron, GA 31008. Jerry A. Payne, Entomologist, Southeastern Fruit and Tree Nut Research Laboratory, USDA, SEA/AR, P.O. Box 87, Byron, GA 31008. Plant Dis. 64:997-999. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1980. DOI: 10.1094/PD-64-997.

High carbon dioxide (CO₂) atmospheres reduced the mycoflora and controlled in-shell weevils in pecans stored under accelerated storage conditions of 7 C and 65% relative humidity. After 5 mo in atmospheres of 21% oxygen (O₂) and 30% CO₂, pecan weevil mortality was 100%, total mycoflora isolated from kernels was significantly reduced, and off-flavors had not yet developed in the kernels. In atmospheres of 3 and 10% CO₂ (plus 21% O₂) or in 1% O₂ (with or without 30% CO₂), weevil mortality was less than 100%. Objectionable off-flavors developed in high CO₂ atmospheres after 6 mo. Alternaria and Pestalotia spp. were the fungi most frequently isolated from pecans held in air. After 5 mo in high CO₂ atmospheres, Alternaria, Penicillium, and Fusarium spp. were the most frequently isolated fungi.

Keyword(s): Carya illinoensis, controlled atmospheres, Curculio caryae, modified atmospheres, storage fungi.