Effects of Increasing Doses of Nitrogen Fertilization on Winter Melon Production in the Western Coast of Sicily

The winter melon is largely grown in the open field in the Mediterranean island of Sicily on about 6000 hectares. Nitrogen fertilization is a key aspect of a winter melon cultural system as it can dramatically improve fruit production and play a crucial role on fruit quality attributes such as fruit size, colour and uniformity. An experiment was performed to determine the influence of increasing doses of nitrogen fertilization on fruit yield and quality of winter melon. The trial was conducted in the north-western coast of Sicily near Buseto Palizzolo in the province of Trapani, 250-m elevation. Plug type transplants cv. Helios were planted in the first week of May. A transparent polyethylene film was applied for mulching. The crop received by preplant broadcasting 150 kg ha-1 P. Nitrogen (0, 50, 100, 200 or 300 kg ha-1) and K (250 kg ha-1) were applied by fertigation throughout the season. The lowest yield (17.6 t ha-1) was recorded in absence of nitrogen fertilization. Applying 50, 100 and 200 kg ha-1 N resulted in 26.0, 27.6 and 27.7 t ha-1 fruit production, respectively. Yield was highest (31.8 t ha-1) at 300 kg ha-1 N. Individual fruit weight increased as the dose of nitrogen fertilization increased reaching 2500 g at the highest doses. Total soluble solids (TSS) decreased as nitrogen fertilization increased.