La création de variétés résistantes: Cas du riz et de la pyriculariose

Abstract

Knowledges obtained about rice (Oryza sativa) domestication and the distribution- of the rice blast fungus (Pyricularia oryzae) proove a long coevolution of the plant and its parasite. Analysis of rice resistance to blast demonstrates the occurence of complex mecanisms. So far monogenic specific resistance genes have not been useful because of their fast breakdown due to the development of virulent races. Study about mecanisms of variability of P. oryzae demonstrates that they are similar to ones of others Ascomycetes. So usual strategies of breeding for resistance can be applied. Obtention of rice varieties with a high level of partial polygenic resistance has led to the success of their cultivation. © Société botanique de France, 1989.