Sowing dates, nitrogen rates, pruning and yield of Lagenaria siceraria (Molina) Standl. in southern Italy.

Two years of trials with bottle gourd, Lagenaria siceraria (Molina) Standl., were conducted in southern Italy to evaluate the influence of two sowing dates (May and June), four N rates (100, 150, 200 and 300 kg.ha(-1) in the first year, and 0, 50, 100 and 150 kg.ha(-1) in the second year) with pruning of side shoots (first 4 or 8 basal) or main shoot (100 or 180 cm above ground level). The number of marketable fruits per plant and marketable yield was both reduced by 66% when the sowing dates were delayed. Higher marketable yields were obtained with nitrogen treatments of 100 and 150.kg ha(-1), (an average of 20.4 t.ha(-1) in 1994 and an average of 15.2 t.ha(-1) in 1995). Additionally, the 150 kg.ha(-1) N treatments decreased the time to achieve 25% of marketable yield by 5 days in 1994, and 6 days in 1995 when compared to other N rates. Pruning the first 4 basal shoots + main shoot at 180 cm above ground level in the first year or pruning the main shoot at 100 cm above ground level in the second year, decreased marketable yield by 46 and 24 %, respectively compared to the control. The yield of unpruned plants occurred earlier than for pruned plants.