CALIBRATION OF THE THERMAL DISSIPATION PROBE FOR ATEMOYA: (Annona squamosa x A. cherimola)

Abstract

When determining plant transpiration (TR) using the thermal dissipation probe method, it is necessary to calibrate the sap flow (SF) estimation equation for each species under study, and thus obtain reliable information about the water demand of crops. This study aims to calibrate the equation used to determine SF using the thermal dissipation probe for atemoya cultivation. The experiment was conducted in the experimental field of the Universidade do Estado da Bahia, Juazeiro, Northeast Brazil. Atemoya plants in the initial phase of development were transplanted into 21.5-l pots arranged on weighing platforms that acted as lysimeters. The SF was determined by the thermal dissipation probe method using 1-cm-long probes. The angular coefficient of the Granier equation was adjusted by minimizing the absolute deviations between the accumulated daily SF and TR measured using the lysimeter. The results demonstrated that the application of the Granier method is satisfactory for estimating the TR of the atemoya and that it is necessary to adjust the angular coefficient of the equation. The mean absolute error between SF and TR was 3.1%.