Produção e evapotranspiração do melão cantaloupe, submetido a diferentes lâminas de irrigação em ambiente protegido

Abstract

Melon is the second most exported fruit in Brazil, being the state of Rio Grande do Norte the main producer in Brazil. The present study aims to determine the production and evapotranspiration of cantaloupe melon in a greenhouse. The research was carried out in a greenhouse, in the municipality of Mossoró-RN, using an automated drip irrigation system. The treatments were five irrigation depths determined in % of crop Evapotranspiration (ETc) estimated by the FAO method, distributed in: 120% (T1), 100% (T2), 80 (T3), 60% (T4) and 40% (T5). The ETc and the Culture Coefficient (Kc) were determined in the T2 and T4 treatments using calibrated automatic weighing micro-lysimeters with automatic readings. The analysis of the plant growth was verified by the weight of the Total Dry Mass (PMS) and the Foliar Area (AF). The production analysis was determined by the Average Fruit Weight per plant (PMF). The coefficient of correlation above 99% for the calibration of the micro-lysimeters showed the efficiency of the sensors of weights used in the estimation of Kc's. The mean ETc values found were 1.96 and 1.74 mm dia-1, for T2 and T4, respectively. The total irrigated leaf was 210.39 mm, slightly higher than that found by the FAO ETc that was 203.93 mm. The mean Kc results found in T2 were higher in phase I and III and lower in the final phase of culture when compared to the values of the Kc of FAO. A significant difference was obtained for PMS, with T1 and T2 treatment being statistically equal and superior to other treatments. In the case of PMF, the T1 treatment was statistically equal to the other treatments. Although there was no difference between the PMF averages, the T1 obtained a production 24.76% higher than the T5.