Bananas are the second most important product for Colombian exports. To meet the demand of international markets, high quantities of chemical fertilizers are needed, but they represent high costs and can be dangerous for the environment. Plant growth promoting rhizobacteria (PGPR) can, at least in part, replace chemical fertilizers.
Technologists at the AGROSAVIA Institute (Colombia) have evaluated the effect of nine PGPRs of the genera Bacillus and Pseudomonas on banana growth. Banana seedlings were produced through tissue culture and acclimatized in greenhouses. The plants were inoculated with rhizobacteria and the growth parameters (plant height, number of leaves, leaf area, pseudostel thickness, fresh weight and dry weight of root and shoots) were evaluated after 55 days.
"The results showed that the two best PGPRs, Bs006 and Ps006 previously identified as Bacillus amyloliquefaciens and Pseudomonas fluorescens, were respectively able to promote banana growth in a way similar or even slightly higher than 100% of chemical fertilization. Root tissues obtained by fluorescence in situ hybridization (FISH) were selected for further characterization of radical colonization by electron microscopy and confocal microscopy", the researchers explain.
"Both rhizobacteria, P. fluorescens (Ps006) and B. amyloquifaciens (Bs006), showed the ability to colonize banana roots, but Bs006 appeared faster than Ps006 in the colonization process. This work has shown that the inoculum of rhizobacteria Bacillus amyloliquefaciens (Bs006) and Pseudomonas fluorescens (Ps006), could partially replace the chemical fertilization of banana plants obtained from tissue culture and therefore could be used for the formulation of a new biofertilizer".
