Hongo endomicorrízico y bacteria fijadora de nitrógeno inoculadas a Coffea arabica en vivero

endomycorrhizic fungi and nitrogen-fixing bacteria inoculated in coffee nurseries. in order to study the effect of bio-fertilization of coffea arabica l. with azospirillum brasilense and glomus intraradice a trial was established in a nursery at the experimental station rosario izapa, chiapas, mexico from september 2005 to april 2006. we used a andosol-mollic soil typical of the soconusco coffee region of chiapas, mexico. a. brasilense had a concentration of 100 x 106 bacteria per gram of peat and the mycorrhizal fungi of 40 spores per gram of soil with 95% infection of the root system of onion. the treatments were the microorganisms alone, the combination of both, and the control without microorganism, which were arranged in a randomized complete block design. morphological and physiological yield components were evaluated every 30 days from the second month to seven months. the content of n, p and ca in plant tissue was determined. the results were analyzed statistically and differences between treatments were compared according to tukey 5%. the results indicate a differential response of microorganisms. a. brasilense induced greater root development and the double symbiosis g. intraradices + a. brasilense enhanced the development of stems and leaf blades. the content of n, p and ca are presented in a manner consistent with g. intraradices.