Fruit Physiological Disorders
Apple: Bitter Pit
Fruit located on vigorous, leafy, upright growing branches have a greater potential to develop bitter pit than does fruit that develops from spurs or on horizontal wood near the tree's main frame. Young trees that are just coming into bearing are the most susceptible. Immature fruit are more susceptible to bitter pit than fruit harvested at the proper harvest maturity. Older trees, which are less vigorous and produce larger crop loads, reduce their susceptibility to bitter pit except in the very sensitive cultivars.
Highly Susceptible Cultivars
Less Susceptible Cultivars
Preharvest sampling for bitter pit is possible. Two weeks before harvest select large fruit from upright limbs of light cropped, vigorous trees. Dip the fruit in a solution of 2,000 ppm ethephon in water (about 1½ teaspoons of ethephon to one gallon of water) to hasten the ripening process. Hold the fruit for two weeks at room temperature. If bitter pit develops, delay the harvest as long as possible. Cool the harvested fruit as soon as possible and delay the packing for at least four weeks. The delay will allow the bitter pit to fully develop. The affected fruit is then removed during the packing process.
Integrated Pest Management For Apples and Pears. University of California, Division of Agriculture and Natural Resources, Publication 3340, 1991. ISBN 0-931876-94-X, Library of Congress Catalog Card No. 91-65337.
Bitter Pit of Apples. University of California Cooperative Extension Publication, Division of Agricultural Sciences, Leaflet 2712, 1975.
Date1991 & 1975
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How to Cite
Author(s) names. Initial publication or update date (located at the bottom). Title. Link to the specific Fruit Physiological Disorders webpage (Accessed date)
Example: Mitchell, F. G., G. Mayer, and A. A. Kader. 1980. Injuries cause deterioration of sweet cherries. California Agiculture 34(3):14-15.