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Hybrid squash (Cucurbita maxima L. cv. Delica) was grown at five levels of nitrogen (N) at each of five levels of potassium (K), and at five levels of phosphorus (P) at each of two levels of N at Pukekohe, New Zealand. Destructive samples were taken on three occasions during early growth and fresh weight, dry weight, and nutrient contents were measured. The fruit was harvested, and yields and nutrient contents determined, when the crop was mature. Nutrient supply strongly affected plant growth and tissue nutrient concentrations measured 16 days after emergence. Growth differences were maintained until harvest, but differences in tissue nutrient concentrations declined during growth. Fruit yields closely reflected the differences in early growth, increasing from 29 to 38 t/ha with N additions up to 160 kg/ha, from 25 to 38 t/ha with K additions up to 320 kg/ha, and from 22 to 45 t/ha with P additions up to 320 kg/ha. Yield differences were mainly attributable to fruit number per plant, rather than to fruit size. Nutrient removals in the harvested fruit were up to N 179, K 203, and P 36 kg/ha.

Two melon (Cucumis melo L. var. reticulatus) cultivars, 'Prince PR' and Tenkei', were grown under PVC cloches at Pukekohe, New Zealand, with nitrogen (N) fertiliser applied at 30 or 120 kg/ha, and with vines pruned to varying extents to modify the total number offruit retained on each plant. Yields and quality of fruit at maturity were determined. Increasing the N application from 30 to 120 kg N/ha increased total fruit yields by 11 % and 28% for 'Prince PR' and 'Tenkei' respectively, and increased marketable yields by 20% and 34%. Largest total fruit yields were recorded where the vines were not pruned. However, average fruit sizes decreased as the number of fruit per plant increased. Highest marketable yields for both cultivars were recorded where four vines per plant were retained. Pruning the vines increased the proportion of marketable yield harvested in the first cut, indicating that fruit maturity was also advanced. None of the treatments significantly affected fruit sugar contents.

Reducing sugar (glucose and fructose) and sucrose are the major free sugars (total sugars) in the carrot root. Striking genetic variation exists for the reducing sugar/total sugar ratio (percentage of reducing sugar). Inbred carrot lines with high and low percentages of reducing sugar were used as parents in establishing various F1, F2, F3 and backcross populations to study the inheritance of root sugars. It was determined that a single major gene regulates the reducing sugar to sucrose balance in carrot roots with dominance for high percentage of reducing sugar. We propose that this gene be designated Reducing sugar, symbolized Rs. This relationship is of interest since sugars in the carrot root are a major storage carbohydrate and a primary component of carrot flavor.

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