Bacteria associated with sugarcane in Northeastern Brazil

Abstract

Sugarcane has a high demand in nitrogen, increasing costs and causing damages to the environment. It is necessary to find alternatives to reduce nitrogen fertilizers use. Diazotrophic bacteria have capacity to promote growth in grass with potential to fix N 2 and solubilize inorganic phosphate. This study aimed to evaluate bacterial community associated with different sugarcane varieties in Northeastern Brazil, select bacteria with plant growth-promoting characteristics, and identify endophytic and epiphytic bacterial lineages in sugarcane. Endophytic bacteria of leaves and roots and epiphytic bacteria of rhizoplane were isolated from three sugarcane commercial varieties and selected for their capacity to fix N 2 and solubilize inorganic phosphate. Bacterial strains from different morphological groups were isolated and a sample of 27 strains with potential for the simultaneous development of these characteristics were selected and identified. The bacterial community that interacted with sugarcane was more associated with rhizoplane and roots regions than with leaves, and had a high potential to fix N 2 and solubilize inorganic phosphate. Bacterial lineages were mainly from genera Pantoea sp. and Burkholderia sp., but there were also genera Enterobacter sp., Klebsiella sp. and Pseudomonas sp. and two lineages at the species level: Pantoea stewartii and Burkholderia cenocepacia.

Associative diazotrophic bacteria inoculated in sugarcane cultivars: implications on morphophysiological attributes and plant nutrition

“…A large diversity of diazotrophic bacteria can establish an association with sugarcane, including strains of the genera Azospirillum, Burkholderia, Herbaspirillum, Gluconacetobacter, and Stenotrophomonas (Baldani and Baldani, 2005;Silva et al, 2016). Gluconacetobacter diazotrophicus is an endophytic diazotrophic bacterium isolated from sugarcane roots and stems (Cavalcante and Döbereiner, 1988).…”