Abstract
The Gharb plain in Morocco suffers from water excess in winter and from water deficit during the spring and summer. This explains the low profitability of the investments in irrigation agreed by the Moroccan state and low yields of winter crops. Furrow irrigation systems may be a way to increase water productivity by improving the surface drainage in winter, and by irrigating the crops efficiently in spring and summer. The aim of this study was to assess the hydraulic performance of furrow systems and its agronomic impacts based on an experimental and a modelling approach. Yields were simulated for a series of 11 climatic years (1995–2006). Results clearly showed the advantage of the furrow system whatever the sowing dates. These results confirmed that to improve the water productivity of winter crops in the context of the Gharb scheme, attention has to be paid to surface drainage. Copyright © 2009 John Wiley & Sons, Ltd.