The objective of this work was to evaluate the effect of five trickle irrigation frequencies to obtain high yields and maximum water use efficiency in a melon crop cultivated in sandy soil of the Coastal Tablelands of Piauí, Brazil. The experiment was carried out in an experimental area of Embrapa Meio-Norte in Parnaíba, Piauí State, Brazil, latitude 3º5' S, longitude 41º47' W and altitude 46.8 m. A randomized block with five treatments and six replications was used, with irrigation frequencies of 0.5, 1.0, 2.0, 3.0 and 4.0 days. The total and commercial yield and water use efficiency were evaluated. The highest total yield (77.985 kg ha-1) and the maximum water use efficiency by melon crop (282.83 kg ha-1 mm-1) were obtained with an irrigation frequency of one day. The irrigation frequencies of 3 and 4 days or higher are not recommended for the melon crop, and if the water is scarce an irrigation frequency of one day should be used.
drip irrigation; muskmelon; irrigation interval
