Water requirements, water and radiation use efficiency: parameters in order to evaluate the introduction of new crops in the Mediterranean environment.

摘要

Field studies were conducted under a typical Mediterranean climate in southern Italy during 1992-95 on three crops: kenaf [Hibiscus cannabinus], sweet sorghum and Jerusalem artichoke. The relationships between crop water use, light interception andcrop dry matter production were examined on Vertisols. A comparison between the values of WUE (Water Use Efficiency) and of RUE (Radiation Use Efficiency) allowed an evaluation of the crops capacity to utilize water and the energy resources of the environment. Sweet sorghum provided higher values of WUE and RUE (4.8 kg/m3 and 3.3 g/MJ, respectively), than kenaf with 2.3 kg/m3 of WUE and 2.6 g/MJ of RUE and Jerusalem artichoke with 2.5 kg/m3 and 2.0 g/MJ, respectively. Intense irrigation regimes are necessary to obtain high crop yields of kenaf and sweet sorghum. For Jerusalem artichoke, water use could be reduced by 50% (from 556 mm to 264 mm) and tuber dry matter production decreased by only 17.2%.