Improved sources of resistance to ascochyta blight in chickpea

Successful chickpea production in western Canada typically requires multiple applications of fungicides to minimize the severity of ascochyta blight (AB) caused by Ascochyta rabiei (Pass.) Lab. Although planting resistant cultivars could be economical and environmentally safer than fungicide use, varieties with a high level of resistance are not available. The objective of this research was to identify potentially useful parents for breeding programs aimed at the northern Great Plains by assessing the AB reaction of 12 desi and 12 kabuli chickpea varieties for their AB reaction on leaves, stems and pods under two fungicide regimes. The experiment was conducted at Swift Current and Shaunavon, Saskatchewan, in 2004 and 2005. Differences in AB severity on leaves, stems and pods, seed yield and 1000-seed weight occurred among varieties at all site-years tested. The variation was greater among kabuli varieties than desi varieties. Ascochyta blight severity was generally lower under the high fungicide regime. A positive correlation in AB severity on leaves, stems and pods was observed, suggesting a lack of organ-specific reaction. Several promising varieties that combined improved levels of AB resistance, high yield, and large seed size were identified.