VIEW ARTICLE

Postharvest Pathology and Mycotoxins

Prestorage Heat Treatment for Control of Decay of Pear Fruit. R. A. Spotts, Oregon State University, Mid-Columbia Agricultural Research and Extension Center, Hood River 97031; P. M. Chen, Oregon State University, Mid-Columbia Agricultural Research and Extension Center, Hood River 97031. Phytopathology 77:1578-1582. Accepted for publication 24 June 1987. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/Phyto-77-1578.

The effects of prestorage heat treatment and relative humidity during heating on fruit quality and incidence of decay of pear fruits caused by Botrytis cinerea, Mucor piriformis, Penicillium expansum, and Phialophora malorum were studied. Heating of fruit at temperatures from 21 to 38 C for 1–7 days significantly reduced decay caused by P. malorum, and large decreases in decay occurred after 1, 3, and 5 days heating at 32, 27, and 21 C, respectively. Prestorage heating was less effective for decay control in overmature than optimum mature fruits. Dessert quality of fruits heated to 32 and 38 C was not acceptable because proper ripening was inhibited. Less Mucor rot occurred when fruits were heated at 90 than at 100% relative humidity, but relative humidity from 80 to 100% during heating did not affect decay caused by B. cinerea, P. expansum, or P. malorum. Although heating reduced incidence of decay caused by M. piriformis and P. malorum, decay caused by B. cinerea was not affected and was increased in fruits inoculated with P. expansum. When fruits were both wounded and inoculated after heating, no control of decay occurred. However, heating wounded fruits reduced Mucor rot and Phialophora side rot even when fruits were inoculated after heating, indicating that apart from direct effects on the pathogen, heating may promote a wound healing response.