Wheat Culture Water Needs Diagnosis Carried Out in the Sidi Bel Abbes Semi Arid Valley

The Useful Agricultural Area Management Mode in the region of Sidi Bel Abbes reveals prima facie an underutilization of the region’s agricultural potential cause of low rainfall level and particularly random distribution often results in a situation of cruel water stress throughout the phenological stages of cereals.

Some daily, monthly and decadal climate parameters, as rainfalls, Potential Evapotranspiration, Maximal Evapotranspiration and temperature and their evolution studies, related to the different stages of development of this culture, helps to identify the phases during which water consumption is really urging. Knowledge of this plant high water demand allows us to target the best moment to palliate those needs to enhance the final productivity of this crop in the plain of Sidi Bel Abbes northwestern Algeria at the Mediterranean Sea. Works during the 2007 - 2011 campaign on “Waha” durum variety showed that the wheat water needs are bound to variations in the intensity of the climatic demand. This one, taken over from planting to heading stage reached an amount of 396 mm while durum wheat evoluting in terms of maximum irrigation consumes an equivalent of 351.5 mm average of water. This sentence implies the importance of the water problem facing the cereal, especially those of short cycle in the semi arid areas. Durum wheat consumes an average 74% of its needs, worth of 268.60 mm of water over a period from the third decade of March to the first half of May when the rainfall recorded during the same period with an average of 34.46 mm, covers only 13% of total crops water requirements. The large amount of this deficit clearly accused justifies the very pronounced low grain yields recorded in the region. Hence, the productivity of this crop depends crucially on the choice of a tolerant genotype to semi arid conditions on one hand and the use of supplemental irrigation on the other hand taking into account the requirements of the culture. Wheat crop coefficients determined for the region permit an efficient irrigation application