Micromorphometric changes in trunk diameter in relation to mild water stress in field grown vines

Abstract

Continuous measurement of micro variations in the diameter of woody organs provides an early detection of mild water deficits in field grown vines. Trunk diameter variations gives more reliable data than cane diameter variations. Water deficit induces trunk shrinkage and increases the Daily Contraction Amplitude/Potential Evapo Transpiration ratio (DCA/PET). This does not occur on irrigated control vines. Moreover, micromorphometry appears to be an accurate technique for detecting short-term water deficits, because the measurements are continuous. Major constraints in the use of micromorphometry on field grown vines include the positioning of sensor needles on the trunk and the need to maintain fragile equipment permanently in the vineyard. Additionally, this method does not quantify water deficits.