The objective of this study was to evaluate the diversity of Gluconacetobacter diazotrophicus isolates from different sugarcane (Saccharum spp.) varieties. This study was developed using 123 strains from the internal tissues of stems and roots, isolated from 80 species and hybrids of sugarcane, originated from different countries and maintained in two germoplasm collections localized in Bahia and Rio de Janeiro States. Five isolates obtained from coffee plants (Coffea arabica), two from pineapple (Ananas comosus), one from Pennisetum purpureum and 10 strains, which present different electrophoretic patterns, were used in the comparison. Cluster analysis of enzyme-linked immunosorbent assay (ELISA) results suggested that variations were not correlated with the plant species, sugarcane variety, geographic origin, parts of plants nor with sampling time. High nitrogen doses lowered the diversity of G. diazotrophicus.
ELISA; biological nitrogen fixation; endophytic bacteria
