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Incidence of scald in nontreated and DPA (2000 mg·liter-1)-treated `Delicious' apples (Malus domestics Borkh.) was assessed after 8.5 months in 1.5% or 0.7% O2 plus 1.5% CO2 at 0.2C, with and without C2H4 scrubbing. Incidence of scald was high in non-DPA fruit held in 1.5% O2, and DPA treatment reduced scald in fruit held in 1.5% or 0.7% O2. Scald control was better with 0.7% O2 and no DPA `treatment than with 1.5% O2 and a DPA dip. Ethylene scrubbing had no effect on scald in fruit held in 0.7% or 1.5% 02. Susceptibility of fruit to scald-and flesh browning exhibited seasonal variation, which was related to the differences in fruit maturity and the amount of watercore at harvest, respectively. Chemical name used: diphenylamine (DPA).

Summerland McIntosh apple trees (Malus domestica Borkh.)on M.9 rootstock were fertigated for the first 3 yr after planting with all combinations of two rates of N (23.5 and 47.0 g tree−1) and three rates of P (0, 17.5 and 35 g tree−1). During this period, soil pH (0.01 M CaCl2) beneath and near the drip emitters declined from 5.8 to < 4.0. Rate of fertigated N had few measurable effects on the trees. In contrast, fertigated P increased first-year tree vigour, second-year tree yield, and sometimes leaf Ca and Mg and leaf and fruit P concentrations. None of these nutrient concentrations were near critical values. Fertigated P also decreased leaf concentrations of K and Cu, which reached deficiency after 3 yr, and did not ameliorate the decline in tree vigour attributed to soil acidification. Increased Mn concentration in leaves was the most distinctive plant indicator of soil acidification, while decreased leaf K was the most important basic cation affected. Fruit Ca was not affected by the decrease in soil Ca availability. Key words: Vigour, yield, fruit Ca, leaf K, Mn and Cu

Gala' apples from n~o Summerland sites were harvested at two harvest dates for two growing seasons (1994, 1995) and stored for 6 months in air and controlled atmosphere (CA). At harvest maturity indices were recorded. Afrer storage, -flesh firmness, titratable acidity and soluble solids were determined and sensory attributes were evaluated by a trained sensory panel. In both years, analyses of variance showed apples picked at commercial harvest were signijicantly more crisp, firm, and sour and less fruity and sweet than apples harvested two weeks later. Apples stored for 6 months in CA were more crisp, firm, juicy and sour, had fewer off--flavors, and had greater overall acceptability than apples stored in air. Apples held at 1.2% 0, for 6 months were more crisp than apples stored at either 2.5% 0, or 5 % Q , while apples stored at 5.0% 0 were significantly less firm, juicy, and sour than apples stored using the other 0, concentrations. Apples stored at either I . 2 % and 2.5 % 0, had signrficantly more fruity flavor than apples stored at either 5.0% 0, or in air.