Pumpkin (Cucurbita maxima) is a popular low country vegetable in Sri Lanka and it has become a fundamental crop species in the farming systems of dry and intermediate zones. Introduced hybrid pumpkin varieties are becoming popular in Sri Lanka because of the higher yield. However, there is no fertilizer recommendation for hybrid pumpkin. Local farmers apply high dosages of Nitrogen(N), Phosphorus(P) and Potassium(K) levels which causes increased cost of production and reduced profit. Therefore, a field experiment was conducted to identify the effects of higher N, P and K levels on yield of hybrid pumpkin. The hybrid variety Arjuna was tested under eight different fertilizer levels where the Department of Agriculture (DOA) recommendation was taken as the control and one and half times of that was used as the higher levels of N, P and K. The experiment was arranged in a confounding design with three replicates with two blocks per each. Reproductive parameters and yield parameters viz. yield, number of fruits per vine, fruit width and diameter were recorded. The tested fertilizer levels did not show any significant effect on reproductive parameters and yield parameters of hybrid pumpkin, thus, indicating that the application of higher dosages of N, P and K is not economical. Hence, the DOA fertilizer recommendation is adequate for hybrid pumpkins though the yield is higher when compared to local pumpkin varieties.
O P G Pushpakumari1, K P D Siriwardhane2 and R H M K Ratnayake1
1Department of Horticulture and Landscape Gardening, Wayamba University of Sri Lanka, Sri Lanka
2Regional Agricultural Research and Development Center, Sri Lanka.