Two-Year Old Giant Reed Ecotypes Adaptation to Drought

Morpho-physiological traits that convey two years-old giant reed (Arundo donax) ecotypes (Moroccan and Northern Italy) high drought tolerance and water use efficiency (WUE) have been evaluated in large rhizotrons under semi-controlled environmental conditions. No large differences between the two ecotypes tested was evident in terms of plant height, number of tillers or biomass production. However, an interesting physiological parameter that distinguished both ecotypes under drought was the predawn leaf water potential (LWP), which was closely related to photosynthesis and stomatal conductance but not to the photochemical reactions of photosynthesis. Stomatal control and LWP could be important attributes to improve drought tolerance in giant reed.