Giant reed genotypes from temperate and arid environments show different response mechanisms to drought.

Studies at the root level and how the root-shoot interactions may influence the whole crop performance of giant reed (Arundo donax L.) under limited water conditions are largely missing. In the present study, we illustrate the effects of water stress on some phenotypic traits at the root-shoot levels of two giant reed genotypes (from Morocco and Northern Italy) that were reported to have different adaptive hydraulic stem conductivities despite the limited genetic variability of the species.