Atemoya sap flow estimation as a function of leaf area and reference evapotranspiration

Abstract The aim of this study was to quantify the water consumption of two atemoya cultivars in irrigated orchards using the thermal dissipation probe (TDP) method, relating transpiration with leaf area and evaporative demand of the atmosphere. The experiment was carried out in two atemoya orchards with young and adult plants of ‘Gefner’ and ‘African Pride’ cultivars at the experimental field of the University of the State of Bahia, in Juazeiro-BA. Plants sap flow was determined by TDP and vegetative growth, and meteorological variables were obtained. The sap flow of young atemoya plants reached maximum values of 10.2 and 8.4 L plant-1 day-1, in ‘Gefner’ and ‘African Pride’ cultivars, respectively. In adult plants, these values were 50.1 L plant-1 day-1 in ‘Gefner’ cultivar and 98.2 L plant-1 day-1 in ‘African Pride’ cultivar. The relationship between sap flow and leaf area showed linearity only for a given leaf area range, in both cultivars and orchards. Sap flow estimated from the product between leaf area and reference evapotranspiration can be used provided that the leaf area limits in which this relationship occurs, in each variety, are considered.