Effect of Different Levels of Nitrogen on Yield of Colocasia (Colocasia esculenta) at District Malakand Dargai

摘要

A field experiment was conducted to evaluate the response of colocasia (Colocasia esculenta) to different levels of 0, 60, 90, 120 and 150 kg N ha-1 under farmer’s field condition at Garhi Usmani Khel, District Malakand Dargai during 2013. The experiment was laid out in Randomized Complete Block design with three replications and treatment plot size of 2.74 × 2.43 m2. All levels of N in the form of urea along with uniform basal doze of 90 kg P₂O₅ ha-1 as Triple Super Phosphate (TSPPP) were applied to soil at time of seed bed followed by thorough mixing. Seeds of colocasia c.v. local variety were sown in these plots with row spacing of 30 cm and plant to plant distance of 12 cm in February, 2013. The results showed that application of N produced significantly higher colocasia tuber yield, number of tubers plant-1, 1000-tubers weight and size of tubers (mean length and diameter) over control but the differences among levels of N were nonsignificant. However, some parameters like tuber yield was maximum at 60 kg N ha-1 and tuber size especially the length of colocasia tuber was maximum at 150 kg N ha-1 suggesting that the response of each parameter was different to N levels. Based on maximum relative yield (100%) and increase over control (46.1%) still at lower N levels of 60 kg N ha-1, this level seems to be appropriate level for colocasia under the prevailing soil and climatic conditions.