New Ascochyta resistant lentil varieties

Abstract

Ascochyta blight, caused by the fungus Ascochyta babae f.sp. L. is the most important lentil disease in Saskatchewan. Laird lentil is grown on 70 to 80% of the lentil area in Saskatchewan. It has extra large seeds that often command a premium in many export markets. When Laird was registered in 1978, it had some resistance to Ascochyta blight, but Morrall at the University of Saskatchewan has shown that the Ascochyta has become more aggressive on Laird lentil in recent years. The other major lentil variety in Saskatchewan is Eston and it always has been rated susceptible to Ascochyta. In addition, the summers since 1990 have been relatively cool and moist in most of the lentil growing area of Saskatchewan, resulting in several Ascochyta infection in many lentil fields. This has necessitated spraying of many of these fields with Chlorothalonil (Bravo), sometimes twice, in order to minimize losses in yield and quality. Fungicide spraying is expensive and may cause environmental damage. Breeding of Ascochyta resistant cultivars is the least costly and most environmentally benign method of controlling Ascochyta blight of lentil.