Prohexadione Calcium and Naphthalene Acetic Acid Sprays Improve Fruit Size and Maintain Fruit Quality of 'Castlebrite' Apricot

Several orchard management practices and postharvest strategies have been adopted to increase productivity and maintain fruit quality. Growth regulator sprays have been widely used to improve the size of stone fruits. The aim of this study was to evaluate the effect of sprays of different combinations of prohexadione-calcium (P-Ca) and naphthalene acetic acid (NAA) on 'Castlebrite' apricot trees, particularly on tree yield and maintain fruit quality after a cold storage period. The treatments were: T0 = control; T1 = P-Ca spray with 10 cm-long shoots, spray with P-Ca 10 d after, and spray with P-Ca 20 d after; T2 = NAA spray with 10 cm-long shoots, spray with P-Ca and NAA 10 d after; T3 = NAA spray with 10 cm-long shoots; T4 = NAA spray with 10 cm-long shoots, spray with NAA 10 d later. The harvested fruit was stored in cold storage chamber for 0, 20 and 40 d, and then evaluated the quality attributes. Fruit quality was evaluated instrumentally and by sensory analysis conducted by a trained panel and a consumer test. Sprays that combine P-Ca and NAA induced a significant increase in mean fruit mass and yield compared to the control. Negligible differences were observed in the acceptability and sensory quality of the fruit.