Summary Completely matured tamr stage dates are widely available and consumed throughout the year. However, for some date varieties, the earlier khalal stage crunchy fruit is considered a premium product. This work examines the use of modified atmosphere packaging to extend the shelf life of khalal dates under refrigerated conditions. Modified atmosphere packaging with 10% or 20% CO2 in air was successful in reducing the rate of the ripening processes while control‐packaged dates showed signs of ripening development such as significant weight loss and darkening in date colour (identified visually and as low lactic acid bacteria measurements at 18 and 27 days after packaging), similar to that observed in tamr stage fruit.

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The effect of soil-applied nitrogen on the growth and yield of 12-year-old apricot Prunus armeniaca cultivar Moorpark trees growing on an orthic Tenosol in the Riverland region of South Australia was studied over 3 years. The experiment was set up in a randomised complete block design with 6 annual rates of nitrogen (0, 250, 500, 750, 1000 and 1250 g/tree.year) applied in the form of ammonium nitrate. Application was split into 30% at budburst, 30% 6 weeks after budburst and 40% after harvest. Growth in trunk circumference was significantly greater at 750 and 1000 g/tree.year than at the other rates of nitrogen. In years 1 and 2, the weight of water shoot growth removed at pruning was significantly higher at nitrogen rates of 750–1250 g/tree.year than from trees that received no nitrogen. It is suggested that for Moorpark apricots growing on an orthic Tenosol, applying nitrogen at rates of 750 g/tree.year and above produces levels of water shoot growth that are undesirable for tree management. Nitrogen application resulted in darker and more vivid green leaves as measured with a Minolta Chroma Meter. Concentration of nitrogen in mid-shoot leaves was increased with increase in applied nitrogen. Fruit size was significantly increased by applied nitrogen in year 1, but fruit size was not significantly affected in years 2 and 3. Nitrogen application increased fruit set in the second and third year. Yield of fresh fruit was not significantly affected in the first year, but was in subsequent years with the maximum yield obtained at a rate of 1000 g/tree.year of nitrogen in both years. Yield of dried fruit followed similar trends to that of fresh fruit. Fruit maturation was delayed by 4 to 8 days by nitrogen application. After 3 years, applying nitrogen at 1250 g/tree.year the pH of soil in the top 15 cm was 4.7 compared with 6.7 where no nitrogen was applied.

Summary. Thinning at full bloom was compared with thinning at 3 stages of fruit development and the effects on size, total soluble solids level (TSS) and yield of apricots are reported. In 2 seasons separate branches of 9-year-old Moorpark apricot trees were hand-thinned to a density of 1 blossom or fruit per 50 mm of fruiting wood. Times of thinning were at full bloom, 5–15 mm size fruit, stone tip hardening and 21 days post stone tip hardening. These treatments were compared with an unthinned control. Experimentation was carried out at Loxton, South Australia. All thinning treatments reduced the yield of fresh fruit. Thinning reduced yield of dried fruit irrespective of timing in the first season but only at the 5–15 mm diameter fruit timing in the second season. Total soluble solids level of the fruit was increased by thinning which tended to improve drying ratio. Compared to the unthinned control all thinning treatments increased the size of fresh fruit. Mean fruit weight and diameter progressively decreased as thinning was delayed from full bloom till stone tip hardening. Thinning at full bloom produced higher yields of 35-mm-grade dried fruit than other treatments. To achieve the greatest benefit from thinning it should be carried out at blossoming.

The effects of soil applications of nitrogen on the quality of fresh and dried fruit from 12-year-old apricot Prunus armeniaca cultivar Moorpark trees growing on an orthic Tenosol in the Riverland region of South Australia were studied over 3 years. The experiment was set up in a randomised complete block design with 6 annual rates of nitrogen (0, 250, 500, 750, 1000 and 1250 g/tree.year) applied in the form of ammonium nitrate. Application was split into 30% at budburst, 30% six weeks after budburst and 40% after harvest. Firmness of fruit was significantly reduced as the rate of applied nitrogen increased. The flesh of individual fruits ripened more evenly when 0 or 250 g nitrogen/tree.year was applied, compared with rates in the range 500–1250 g nitrogen/tree.year. Application of nitrogen significantly increased the pH of fruit. The total soluble solids level of fruit from trees that received 0 or 250 g nitrogen/tree.year, was significantly lower than from trees that received 750 or 1250, but not 1000 g nitrogen/tree.year. Application of nitrogen did not significantly affect the concentration of sulfur dioxide in fresh fruit measured after sulfuring, but the concentration of sulfur dioxide in fruit at the completion of drying was significantly increased. The application of nitrogen did not affect the drying ratio of fruit. Nitrogen application increased the rate of darkening of dried apricots in storage in each of the three years. Relationships were found between time taken for dried apricots to darken to an unacceptable level and nitrogen concentration in harvested fruit. It is suggested that to assist in the management of darkening of dried apricots in storage, annual nitrogen application rates on an orthic Tenosol need to be below 500 g/tree.year and ideally below 250 g/tree.year.