This study, was carried out to determine effects of some growth regulators applications on storage period on Valencia orange. In the first year of experiments fruits were treated with 0 ppm 2,4-D and 200 ppm 2,4-D. In the second year, 0, 100, 200, 400 ppm 2,4-D, 200 ppm 2,4-D + 100 ppm GA3 and 400 ppm 2,4-D +100 ppm GA3 combinations were applied after harvest. The fruits were wrapped with hutbak paper and were put in cardboard boxes and then were placed in a cold store set at +4°C temperature with 85-90% relative humidity for five months. Fruit quality criterias as Juice Rate (%), acidity(%), pH, TSS(%) and physiological and pathological losses were determined at monhly intervals during storage period. Results of the research showed that 200 ppm 2,4-D + and 2,4-D + GA3 treatments were the most effective for keeping the green button and reducing fruit rotting. Growth regulator treatments were given succesful results on five months storage of orange fruit in suitable conditions.

This study, was carried out to determine effects of some growth regulators applications on storage period on Valencia orange. In the first year of experiments fruits were treated with 0 ppm 2,4-D and 200 ppm 2,4-D. In the second year, 0, 100, 200, 400 ppm 2,4-D, 200 ppm 2,4-D + 100 ppm GA3 and 400 ppm 2,4-D +100 ppm GA3 combinations were applied after harvest. The fruits were wrapped with hutbak paper and were put in cardboard boxes and then were placed in a cold store set at +4°C temperature with 85-90% relative humidity for five months. Fruit quality criterias as Juice Rate (%), acidity(%), pH, TSS(%) and physiological and pathological losses were determined at monhly intervals during storage period. Results of the research showed that 200 ppm 2,4-D + and 2,4-D + GA3 treatments were the most effective for keeping the green button and reducing fruit rotting. Growth regulator treatments were given succesful results on five months storage of orange fruit in suitable conditions.