The extraspecific transfer of genes into cultivated plants is of considerable interest both in basic and applied terms (Sears, 1956; Riley and Kimber 1966). The wild grass Aegilops ventricosa has been recognised for almost 30 years as an important potential donor of genes that determine characters of agronomic interest. More specifically, Sprague (1936) discovered in this species a high level of resistance to the fungus Pseudocercosporella herpotrichoides, which causes eyespot disease. This disease is responsible for considerable lodging and reductions of yield in extensive áreas of wheat cultivation. The level of resistance of wheat cultivars is too low, even among the less susceptible ones (Capelle Desprez and Cerco) and no single genes for resistance had been described in any species. Attemps to transfer resistance from Ae.ventricosa to wheat had been only partially successful. The purpose of this paper is to review work carried out in our laboratory for the past 12 years on the transfer of genes between these two species. This work has led to the recent demonstre^ tion of a major dominant gene for resistance, which confers a high level of resistance to cultivated wheat
