Effect of Supplementary Irrigation on Agronomical and Physiological Traits in Durum Wheat (Triticum durum Desf.) Genotypes

Drought, one of the abiotic stresses, is the most significant factor restricting crop production in large agricultural fields of the world. Wheat is generally grown on arid-agricultural fields. Drought often causes serious problems in wheat production. Ten durum wheat (Triticum durum Desf.) genotypes were tested under rain-fed (T0) and three irrigated treatments (T1 = 50 mm at Booting stage, T2 = 50 mm at Booting and 15 mm at heading stages and T3 = 50 mm at Booting and 30 mm at heading stages) in semi-arid conditions of Eastern Algeria. Grain Yield, components of yield, heading evolution, leaf relative water content, leaf specific weight, grain filling rate and duration and chlorophyll content were measured. The irrigation treatments affect significantly all characters. Application of 50 mm of irrigation at booting stage increased significantly grain yield by 23%, compared to rain-fed treatment. Another supplementary irrigation of 15 or 30 mm, at heading, increased significantly grain yield by 45 and 61%, respectively. Stressed condition affects negatively thousand kernel weights (105%). In addition, combined analysis of variance showed high genetic variation for all parameters measured, excepted leaf relative water content and leaf specific weight, when measured at heading stage suggesting the possibility of selecting tolerant genotypes for drought tolerance under semi arid condition.