Productivité de l’eau du blé dur irrigué face à la variabilité climatique

The objective of this work is the estimation for irrigated durum wheat of water productivity (WP) levels and gross margin of economic return in relation to regional pedoclimatic variability. The analysis is based on data obtained from monitoring production plots located in nine governorates in Tunisia over eight cropping seasons. Farmers'intra and inter-regional performances are evaluated through technical efficiency scores, using DEA (Data Envelopment Analysis) calculation method. The results obtained on a total number of 373 cases show mid-efficiency of farmers. Pedoclimatic factors seem to be responsible for the decrease of WP by up to 30%. The gross margins increase by 360DT/ha for each unit increase of WP till 12kgha(-1)mm(-1). The breakeven point calculated for variable costs increases by 0.2t/ha when the intra-regional efficiency is increased by 0.1 unit.