Effect of Temperature on Development of Premature Ripening in ‘Bartlett’ Pears1

Abstract

Abstract Premature ripening, a physiological disorder of ‘Bartlett’ pears, was induced experimentally by use of temperature controlled limb cages. Exposure to 65° day and 45° F night temperatures for 3-31 days prior to harvest caused an early acceleration in ethylene production and occurrence of the climacteric rise in respiration. These changes were accompanied by fruit softening, increases in soluble pectin and protein N, a more rapid decline in malic acid as well as a decrease in the rate of citric acid accumulation. Treatments with gibberellic acid (GA 3 ), 100 ppm, and succinic acid 2,2-dimethyl hydrazide (Alar), 1000 ppm, counteracted the effect of cool temperature exposure and retarded premature ripening. The disorder did not develop in fruit maintained at 75° day and 60° night temperatures during the experiment.