Variability of pearl millet downy mildew (Sclerospora graminicola) and its implications for breeding for stable and durable resistance

Abstract

Ten pearl millet genotypes (Pennisetum glaucum (L.) R. Br.) were tested for downy mildew (Sclerospora graminicola (Sacc.) Schroet.) reaction in the field at four locations in West Africa and in the greenhouse at Reading University, UK, using collections of the pathogen from the same areas. Some of the test entries showed different reactions at different locations and when inoculated with different isolates. It was found that different pathotypes of S. graminicola exist in West Africa (ICRISAT, 1987). The pathotypes from Bawku Manga (Ghana) and Samaru (Nigeria) were more virulent than the ones from Kamboinse (Burkina Faso) and Bengou (Niger). The breeding line IKM/CVP 39/83/84/351 showed stable resistance over all locations and all isolates at Reading.

Keywords:

• Downy mildew
• Sclerospora graminicola
• pearl millet
• variability
• West Africa

Notes

National Institute of Agricultural Botany, Huntingdon Road, Cambridge, CB3 0LE, UK.