Tabasco pepper transpiration by the heat dissipation probe method

Abstract

Methods of heat supply in the trunk have been widely used to estimate transpiration of woody plants; however, there are few studies about its effectiveness in small plants. This study aimed to calibrate the Heat Dissipation Probe (HDP) method to estimate transpiration and study the influence of natural thermal differences, the estimation of the conductive area and the placement of sensors to estimate transpiration in Tabasco pepper plants. Heat dissipation probes were installed in twenty nine 8-month-old plants, planted in beds, in a greenhouse. The equation for sap flow estimation was calibrated with standard lysimetric measurements in one of the representative plants. The angular coefficient of the equation for estimating sap flow was adjusted by minimizing the absolute deviations between the sap flow and daily transpiration measured in the lysimeter. After ten days of sap flow measurements, all plants were cut above the installation location of the upper probe; images of certain areas were generated and the dimensions of the regions present in the stem were determined. The HDP method with original calibration adjustment, correction of natural thermal differences and with a small sampling to determine the conductive area of the xylem is accurate to estimate the transpiration of Tabasco pepper plants.