Abstract

Rice is the staple food and economic lifeline of Asia. The genus Oryza has two cultivated species and 22 wild species with 10 different genome types. The cultivated rice, Oryza sativa L., is a true diploid with 24 chromosomes but the wild species are either diploid or allo-tetraploid. The wild species have numerous valuable traits such as resistance to biotic stresses, tolerance to abiotic and environmental stresses, and increasing yield potential of rice. We have moved the genes from distantly related wild species into cultivated rice by using the tools of modern biotechnology and have enriched the gene pool of rice. We are beginning to understand the functional characteristics of some key resistance genes. This will enhance our understanding on gene transfer mechanisms from wild species to cultivated rice.