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ameter) and between 25 May and 31 August (sap flow). The variables derived from the
dendrometers raw data are seen in Table 1.
Table 1 – Variables derived from dendrometer raw data
The sap flow (SF) is presented as the daily harmonic mean of the flow rates (L dm-2 h-1 )
recorded during 24 hour periods.
The raw data was statistically analyzed to objectively determine the trend variations on
stem growth, on sap flow and how close they track each other. The method used was
the cumulative sum chart (CumSum) defined as (Eriksson et al., 2006):
??????= ,?=1-?-(,?-?.??).
The CumSum at time step m is the sum of the differences between the previous observations
and , the estimated mean value of all observations. The CumSum chart is a
statistical process control tool, which detects up or down drifts and abrupt changes in
the mean (Korpela et al., 2010).
The five vines on the vicinity of the one fitted with dendrometer and sap flow, were
sampled for their berries to determine their growth.
3 - RESULTS AND DISCUSSION
The dendrometer data shows that the irrigated vine had a stem cumulative growth during
the measurement period of 202.34 m and the rain fed had -209.21 m. The variation
pattern of stem diameter showed that the fluctuations of the rain fed plant were more
accentuated than those of the irrigated vine. Thus, the rain fed vine had an average of
56.29 m for MSD, 55.44 m for DR that resulted in a negative DG of -0.60 m. The
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