Improving water productivity of Crops in the Mediterranean region: case of cereals
Mohammed Karrou, Mohamad El Mourid. (17/5/2009). Improving water productivity of Crops in the Mediterranean region: case of cereals. Lebanon.
Water scarcity and drought are the main constraints of crop production in the Mediterranean basin. However, the situation is more alarming in the southern and eastern parts of the basin. Although many technologies have been developed by scientists in the region to cope with these environmental problems, the difference between the farmers' and potential achievable yields remain in general highly significant in both rainfed and irrigated areas. A large dissemination of the improved management packages can help close the observed yield gap. Moreover, because water shortage and drought will be more intense in the Mediterranean due to the effects of the global warming, the increase of land productivity should not be anymore the only objective, but more emphasis has to be put also on the improvement of the productivity per unit of water consumed by the crop. This will ensure water saving and higher global production. In this paper, the concepts of water use efficiency will be presented and strategies of water productivity increase will be discussed. In the rainfed areas, these strategies are based on better crop and soil management and the improvement of genetic makeup of the cultivated plants to capture more water for use in transpiration, to use CO2 more effectively in producing biomass and to convert more of the biomass into grain or other harvestable products. In the irrigated zones, water losses at different steps of water use in crop production should be reduced and water productivity has to be increased by the application of the required amounts of water and nitrogen at critical stages. Moreover, supplemental irrigation and wide spaced furrows and raisedbed planting irrigation technologies should be used to save water and irrigate more area. Finally, varieties with higher water and nitrogen use efficiencies should be developed.