Transfer of a dominant gene for resistance to eyespot disease from a wild grass to hexaploid wheat

Abstract

Eyespot disease, caused by the fungus Pseudocercosporella herpotrichoides, is responsible for considerable lodging and reductions of yield in extensive areas of wheat cultivation in North and South America, Europe, New Zealand, Australia and Africa¹. The level of resistance of wheat cultivars is too low, even among the less susceptible ones (that is, Cappelle Desprez and Cerco) and no genes for resistance have to date been characterized in any species. Sprague² found a high level of resistance to this disease in the wild grass Aegilops ventricosa and several workers have attempted its transfer to cultivated wheat with only partial success^3–5. We report here a major dominant gene for resistance, which has been transferred from tetraploid Ae. ventricosa (genomes D^vD^vM^vM^v) to hexaploid wheat, Triticum aestivum (AABBDD), using tetraploid wheat, Triticum turgidum (AABB), as a ‘bridge’ species.