Preharvest and storage quality of ‘Braeburn’ apple fruit grown under water deficit conditions

Abstract

Six-year-old ‘Braeburn’ apple trees (Mains domestica Borkh.) on MM 106 rootstock were studied to determine the influence of withholding irrigation on fruit composition both before harvest and during storage. Trees were either fully irrigated (I) according to commercial practice, or not irrigated (NI). Rainfall was excluded from the rootzone of all NI trees and three of the six I trees from 105 days after full bloom (DAFB). The NI trees had lower leaf water potential (?) than I trees from 110 DAFB. Fruit were sampled at 2-week intervals from 130 DAFB until 192 DAFB. Some fruit picked at 192 DAFB were placed in cold storage lor 12 weeks at 0°C. Fruit were analysed at 3-week intervals until 84 days in storage. No difference in fruit weight or crop load was observed between treatments. Before the final harvest, NI fruit had higher concentrations of total soluble solids (TSS), titratable acidity (TA), sucrose, sorbitol, and total soluble sugars, and a lesser concentration of nitrogen than I fruit. Soluble sugar levels increased during storage for I and NI fruit. However, larger increases in the concentrations of fructose, sucrose, and total soluble sugars occurred in the NI compared to I fruit. No difference in the concentration of Ca, Mg, K, and P was observed between treatments. The observed differences in composition preharvest and during storage of the I and NI fruit indicate an improvement of some attributes in NI fruit. © 1996 Taylor & Francis Group, LLC.