Influence of Fruit Maturity on the Effect of Postharvest Calcium Treatment on Decay of Golden Delicious Apples. W. S. Conway, USDA, ARS, Horticultural Crops Quality Laboratory, BARC-West, Beltsville, MD 20705. C. E. Sams, USDA, ARS, Horticultural Crops Quality Laboratory, BARC-West, Beltsville, MD 20705. Plant Dis. 69:42-44. Accepted for publication 14 June 1984. 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, 1985. DOI: 10.1094/PD-69-42.

Golden Delicious apples harvested at three stages of fruit maturity were pressure-infiltrated (68.95 kPa) at harvest with 0, 2, 4, 6, or 8% solutions of CaCl₂ and stored at 0 C. After 4 mo, the fruits were removed from storage, wound-inoculated with Penicillium expansum, and incubated for 7 days at 20 C. Fruits were then rated for decay severity and injury and analyzed for calcium content. Fruits harvested 2 wk before the prime harvest period and infiltrated with 8% CaCl₂ solution had twice as much calcium in the flesh as untreated fruits, 25% less decay, and little injury. Fruits picked at prime harvest and infiltrated with 8% CaCl₂ solution had five times the flesh calcium concentration of untreated fruits, 57% less decay, and showed extensive superficial injury. Fruits picked 2 wk after prime harvest and infiltrated with 8% CaCl₂ solution had seven times the flesh calcium concentration of untreated fruits and 67% less decay, but injury extended into the cortex.

Keyword(s): Malus pumila.