The ratio between root and leaf dry weight was always greater in non-irrigated than irrigated plots. (Dichio, B. et al). Root explored a soil volume range from 0.5 m3 in the first year to 16.8 m3 in the seventh year for irrigated plots and from 0.5 m3 to 13.4 m3 for non-irrigated ones.
In non-irrigated plots, canopy growth was drastically reduced while root growth was not restricted as significantly, probably as a defense strategy against water deficit, making for a better root/leaf ratio and consequently greater water availability to the leaves.

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