Afinidad y efecto de Azospirillum sp. en maíz

affinity and effect of azospirillum sp. in corn. the objective of this work was to determine the affinity and effect of azospirillum in corn. this bioassay was conducted in the state of mexico, méxico, during the spring - summer cycle of 2009. the root system of corn palomero toluque？o, cacahuacintle, cónico, chalque？o and h-20, and of teocintle, was collected, and after isolation and purification of strains outstanding in their nitrogenasa activity (n’asa), were reinoculated aseptically in the same varieties at the seedling stage (13 days) under hydroponic culture. root volume was determined, and also used to determine bacterial populations and n’asa at 60 dde, in corn and teocintle. azospirillum did not affect root volumen in relation to nitrogen fertilization, but the comparative study showed that strains isolated from cónico and chalque？o corn, in addition to teocintle, formed more root tissue in chalque？o corn. despite that the largest bacterial population was obtained with the strain isolated from h-28 ans inoculated on corns chalque？o, h-28 and cónico, the highest n’asa was recorded with strains isolated from h-28, palomero toluque？o and chalque？o, inoculated on corn chalque？o. there was a degree of affinity, or effect of the homologous strains, between azospirillum obtained from corns h-28 and chalque？o and their re-inoculation on the same varieties, evaluating the number of azospirills and n’asa, and a survey of azospirillum from recent corns, for ancestors of the same cereal.