The Rate of Water Loss in Relation to Internodes Position and Wood Maturity in Vine Chords

Abstract

The purpose of study was to assess the rate of water loss from the strings of vines in relation to internodes position on vine chords and degree of wood maturity. The biological material was represented by Burgund vine cultivar, to which were analyzed individually all internodes distributed on the chord length (internodes number IN2-19). The rate of water loss and associated parameters (maximum rate of water loss - RWLMax, total drying time - T, time to achieve RWLMax - tRWLMax) were determined from the Burgund vine cultivar, in controlled condition. Parameters studied were associated with dry matter content (refractometric method), degree of maturity of the wood, and internodes positions on chord. RWL Max had higher values in the basal internodes (IN2; RWL Max = 0.252±0.005 g/min) and lower in the apical internodes (IN17-19; RWLMax = 0.202±0.011 g/min). RWLMax distributions values, according to the position of internodes on chord was described by a third degree polynomial function, statistical safety (R2 = 0.949, p<0.01). Dry substance content in internodes (sugar) was correlated with the total time of water loss (T; R2 = 0.945), the time to reach the maximum rate of water loss (tRWLMax; R2 = 0.855), and maximum rate of water loss (RWLMax; R2 = 0.984).