Abstract

Water deficit is one of the important factors limiting crop production in arid and semi-arid regions. This research was conducted in 2007 and 2008 to investigate field performance of three chickpea cultivars (Hashem and Arman from kabuli and Pirooz from desi type) under well watering (I₁: 70 mm evaporation from class A pan), gradual water deficit (I₂ and I₃: 70…90…110…130 and 70…100…130 mm evaporation, respectively) and severe water stress (I₄: 130 mm evaporation). Results showed that with increasing irrigation intervals, leaf proline content increased, while LAI and grain yield were decreased. These reductions were only significant under severe water deficit (I₄) as compared with well watering (I₁). No significant differences in chlorophyll content and quantum yield (F_v/F_m) were recorded among irrigation treatments. LAI, chlorophyll content and grain yield of kabuli type cultivars were more than those of desi type cultivars. It was concluded that gradually increasing irrigation intervals can prevent significant reductions in LAI and grain yield, due to drought hardening of chickpea plants.

Key words: Chickpea, gradual water deficit, grain yield, LAI, proline, quantum yield.