Una estrategia para mejorar la fijacion de nitrogeno

The different stages of a technique developed by CIAT to increase the N fixation of beans are indicated. In stage 1L, the effectivity of native rhizobial strains is assessed; bean nodulation and N fixation are recorded. In stage 1R , rhizobial strains are isolated, purified, authenticated in the lab. As a result, 50 rhizobial strains have been isolated and inoculants prepared. In stage 2, genotype/soil combinations are studied to improve the effectivity of symbiosis through (1) inoculation, which improves the strain component, and (2) plant breeding to increase plant N-fixing capacity. Stage 3 involves on-farm testing of these improved combinations and stage 4 consists of the release and commercialization of the inoculants. Brief reference is made to results obtained in Colombia and El Salvador using this technique. (CIAT)