Effect of gibberellic acid on rind quality and storage of coastal Navel oranges

Abstract

The effects of gibberellic acid (GA3), at various concentrations and application times, on the susceptibility of the rind to injury, the incidence of physiological disorders, and the storage life of Washington Navel oranges were examined over three seasons. Susceptibility of the rind to injury, the incidence of water spot, puffing and creasing, and green mould wastage in stored fruit were reduced by GA3 treatment. Resistance of the rind to puncture increased with increasing GA3 concentration. Early May sprays were more effective than early June sprays in increasing. the resistance of the rind to puncture and decreasing the incidence of puffing and creasing. Split applications were no more effective than single applications at the combined concentrations. There were no undesirable effects on internal fruit quality. Although colour development was delayed by GA3 treatment, with late harvest colour development progressed to a commercially acceptable level while internal fruit quality was still satisfactory.