The objective of this work was to evaluate the effect of four doses of nitrogen (N) and four doses of potassium (K2O) applied through drip irrigation in the melon cultivated in a sandy soil of Costal Tablelands of Piauí. The experiment was carried out at the experimental area of EMBRAPA Meio-Norte, in Parnaíba - Piauí, Brazil (3º5' S e 41º47' W), in a completely randomized block design, in 4 x 4 factorial with three repetitions. The doses used were: 100, 160, 220 and 280 kg ha-1 of N and 100, 190, 280 and 370 kg ha-1 of K2O. The dry matter production, mean weight of the fruit and commercial yield of melon were influenced by N and K2O doses and the interaction between them. The leaf area was influenced by nitrogen dose only. The higher values of dry matter production (93 g plant-1), average fruit weight (1.85 kg) and commercial yield of melon (48.13 t ha-1) were obtained with N and K2O doses of 100 and 190 kg ha-1, 220 and 190 kg ha-1 and 100 and 370 kg ha-1, respectively. The highest leaf area (12,017.40 cm² planta-1) was registered with the application of 100 kg ha-1 of N. Dose of 100 and 160 kg ha-1 of N in combination with 370 kg ha-1 of K2O produced the maximam commercial yield of melon.
Cucumis melo; plant nutrition; drip irrigation
