HARVEST MATURITY, CONDITIONING TEMPERATURE, AND ETHYLENE TREATMENT INFLUENCE INDUCTION OF RIPENING CAPACITY IN 'D'ANJOU' PEAR FRUIT
The relationship between dAnjou pear fruit maturity at harvest and postharvest conditioning necessary to induce ripening capacity at -0.5, 5, or 10°C was studied at two locations in Oregon. Fruit were harvested weekly for five weeks beginning at 66.7 N and conditioned for 10, 20, 30, 40, 50, or 60 d at each temperature. After 7 d ripening at 20°C, fruit firmness was measured and the conditioning duration corresponding to fruit softening to ≤17.8 N was calculated. At -0.5°C, ~60 d were required to induce ripening capacity in fruit harvested at initial maturity. This decreased to a minimum of ~22 d when pears were harvested 28 d later. At 5°C, fruit harvested at initial maturity required ~30 d to achieve ripening capacity, while those harvested 28 d later needed only 2 d. At 10°C, fruit harvested at initial maturity required ~18 d to achieve ripening capacity; pears harvested 21 and 28 d after initial maturity required less than 10 d at 10°C. The relationship between harvest timing and the conditioning duration necessary to induce ripening at each temperature was well-described by second-order polynomial regression. Using this relationship, the conditioning duration necessary to induce ripening capacity in dAnjou pears at -0.5, 5, or 10°C corresponding to specific harvest timings can be calculated from the regression equations. dAnjou pear fruit harvested at 66.7 N treated with 100 ml L-1 ethylene at 20°C for 24 h required additional conditioning of 30 d at -0.5°C, 20 d at 5°C, and 7 d at 10°C to develop ripening capacity. After 48 h in ethylene an additional 20 d at -0.5°C, 8 d at 5°C, and 4 d at 10°C were required. Ethylene treatment for 72 h required no additional conditioning.
Sugar, D. and Einhorn , T.C. (2011). HARVEST MATURITY, CONDITIONING TEMPERATURE, AND ETHYLENE TREATMENT INFLUENCE INDUCTION OF RIPENING CAPACITY IN 'D'ANJOU' PEAR FRUIT. Acta Hortic. 909, 719-724
Pyrus communis, pear ripening