The objective of this work was to evaluate the relation between nitrogen distribution in plants of sugarcane, and the colonization by Gluconacetobacter diazotrophicus and Herbaspirillum spp. The experimental design was a split plot, with four genotypes of sugarcane: SP70-1143 and SP79-2312 (hybrids), Krakatau (Saccharum spontaneum L.) and Chunnee (Saccharum barberi Jesw.), and four times of harvest: 90, 180, 360, 540 days after planting, and four replications. The parameters evaluated were: nitrogen percentage, nitrate, free amino-N, and the most probable number of Gluconacetobacter diazotrophicus and Herbaspirillum spp. population. The percentage of nitrogen showed higher values at 90 days after planting in leaves and apical stems, and the largest concentrations of amino-N occurred in the roots, basal stems, and leaves of SP79-2312 variety and in apical stems of the Chunnee genotype. The largest nitrate accumulation was observed in the basal and intermediary stems, mainly in SP79-2312 variety. Proteic-N was the main component of the total nitrogen content, with the same tendency in different parts of the plant. Highest value of G. diazotrophicus population occured in the roots of SP70-1143, SP79-2312, Krakatau and in the four genotypes of Herbaspirillum spp.
sugarcane; plant nutrition; endophytic bacteria
