The Alvim phytotensiometer is largely used to measure the variation of tree trunck turgescence, which is reduced during the day as a response of the net effect of crown transpiration, and increased during the night due to the recovery which may be total or partial, depending on soil moisture and on the capacity of the plant in relation to water absorption. The readins of the manometer are relative and in many cases do not correspond to the data obtained by other transpiration rate measurements. The present paper consideres a new interpretation of the observed curves, applying them for different kinetic regions, through linear regression functions. From these regressions, the slopes were used as comparative parameters of the trunck turgescence intensity changes, using different plants under different environmental conditions.
phytotensiometer; turgescence; linear regression; angular coefficient