Growth-promoting rhizobacteria as a strategy to improve water stress tolerance in banana (Musa spp.) during nursery

Abstract

The cultivation of Musa spp. is facing increasing losses due to erratic rainfall in tropical growing regions, making it necessary to explore biological alternatives that reduce dependence on irrigation without compromising seedling development. The effect of a consortium of plant-growth-promoting rhizobacteria, capable of forming biofilms in the rhizosphere, on the morphophysiological development of Williams banana seedlings subjected to three levels of water availability during the nursery phase was evaluated. A completely randomised design was used, comprising six treatments and three replicates, with assessments of height, pseudostem diameter, number of leaves, relative chlorophyll content and fresh root weight. The treatments without bacterial inoculation consistently outperformed the inoculated treatments for all variables with statistical significance, achieving the highest performance under the least water-limiting conditions. Inoculation did not induce any detectable improvements in any of the morphological or photosynthetic variables assessed. These results suggest that, under the conditions tested, seedling development depended primarily on intrinsic physiological mechanisms in response to water deficit, rather than on the activity of the bacterial consortium.