Native Bacterial Consortium as a Biofertilizer Strategy in the Cultivation of the Fedearroz 2020 Rice Variety

The use of plant growth-promoting bacteria is a sustainable strategy for reducing dependence on chemical fertilizers in agricultural production.This study evaluated the biofertilizer potential of native bacteria in rice plants (Oryza sativa L.) var.Fedearroz 2020, isolated from rhizospheric soils at the La Victoria experimental center (Monteria, Colombia).Ten samples were collected from soil at a depth of 15cm, which were mixed and used for the isolation of microorganisms in Burk's medium.Biological nitrogen fixation, phosphate solubilization, and indole-3-acetic acid production were evaluated.Five treatments were arranged in a completely randomized block design: inoculation of the bacterial consortium at concentrations of 10 -6 , 10 -⁷, and 10 -⁸CFU mL -1 , chemical fertilization (urea, DAP, KCl), and a control without fertilization or inoculation.Isolate C1 showed the highest nitrogen fixation (3.831mg L -1 ), while C2 showed the highest phosphate solubilization (3171.2mgL -1 ) and indole-3-acetic acid production (35.99mgL -1 ).Molecular characterization identified C1 as Herbaspirillum sp. and C2 as Klebsiella sp., with no evidence of antibiosis.Inoculation of greenhouse plants with the bacterial consortium promoted significant increases in height, root length, number of tillers, fresh and dry weight, number of panicles, number of grains, grain yield, and nitrogen content, with no statistical differences compared to chemical fertilization.These results demonstrate the potential of the Herbaspirillum-Klebsiella consortium as a biofertilizer alternative in rice under controlled conditions.