Improvement of fruit quality and storage potential of 'Braeburn' apple through deficit irrigation

We explored the potential of deficit irrigation (DI) applied at different t imes during the growing season for improving fruit quality and storage pote ntial of 'Braeburn' apple growing in a commercial orchard. Because DI often reduces fruit size, effects of fruit size on fruit quality were also exami ned. The irrigation treatments were: commercially irrigated control (C), ea rly deficit irrigation (EDI) applied from 63 to 118 d after full bloom (DAF B), and late deficit irrigation (LDI) applied from 118 DAFB to final harves t on 201 DAFB. Both EDI and LDI improved fruit quality in terms of increase s in: dry-matter concentration (DMC) at harvest, flesh firmness, total solu ble solids, and total soluble sugars both at harvest and after storage. The DI fruit had less weight loss during storage than did C fruit. Deficit irr igation affected the concentrations of a few individual aroma volatiles but not total volatile concentration. Incidence of physiological disorders was not affected by irrigation treatments. Mean fruit weight was lower in DI t han in C but the difference was not significant. Among the quality attribut es studied, only firmness and DMC were affected by fruit size with their va lues being higher in smaller fruit.