The incidence of external and internal bitter pit in `Cox's Orange Pippin' apple (Malus domestics Borkh.) fruit sprayed with normal therapeutic sprays either with or without Ca salts at 2-week intervals during the growing season was determined after 6 weeks of storage over 7 consecutive years. Following harvest, fruit was either vacuum-infiltrated with CaCI2 or received no further treatment. Although there was a tendency for fruit that had been sprayed and vacuum-infiltrated with Ca to exhibit the greatest degree of bitter pit control, this treatment was not significantly superior to Ca sprays alone. Vacuum infiltration alone reduced the disorder to a lesser extent than Ca sprays and was more effective in reducing external than internal bitter bit. The results suggest that Ca applications over the growing season are superior to postharvest vacuum-infiltration with Ca in the prevention of bitter pit.
Positions of every individual kiwifruit were mapped on each of five eight-year-old vines on a T-bar training system before harvest. The proportion of excessively soft kiwifruit (< 1.0 kgf penetrometer reading at 20C) after 130 days coolstorage at 0C on individual vines ranged from 7 to 45%. Fruit at the distal ends of fruiting canes were significantly heavier and firmer (mean wgt 108.5 gms, mean firmness 1.22 kgf) than fruit closest to the main leader (105.6 gms, 1.18 kgf). Conversely, for multiple clusters, fruit on spurs adjacent to the fruiting cane were heavier than those at the terminal end (109.9 and 103.8 gms), respectively, though firmness of these fruit did not differ significantly. The firmest fruit had less nitrogen, less potassium, less phosphorus and more calcium than the soft fruit. Potential means by which this information could be used to improve fruit storage quality will be discussed.
Integer values used to represent apricot (Prunus armeniaca L.) flower bud growth stages in a phenological scale were adjusted by a simple technique based on cumulative counts of bud observations. Adjusted stage values on a new continuous scale were calculated so that differences between consecutive values were proportional to the frequency with which buds were observed in each growth stage class during the entire assessment period. This meant that adjusted scale values were linearly related to bud development rate at 20 °C. The method was applied to a scale describing flower development from budbreak to petal fall for three cultivars of apricot growing under orchard conditions.