Aislamiento y caracterización de bacterias diazotróficas del género Azotobacter, y su efecto sobre el crecimiento y desarrollo en maíz, variedad INIAP 182, en la Estación Experimental La Argelia

Abstract

This research aimed to evaluate the effect of diazotrophic bacteria on morphological parameters and biomass in the maize variety INIAP 182 "Almendral". The diazotrophic bacteria used in the experiment in a greenhouse and in interaction with the cultivation of maize, were those that presented the best morphological, physiological characteristics, and those genetically identified by means of molecular biology studies and corresponded to N-fixing bacteria as in the case of Azotobacter y Beijerinckia. A total of 6 treatments were conducted in the research, T1 (Pin2-Azotobacter vinelandii), T2 (C5 - Azotobacter vinelandii), T3 (Pin7 - Beijerinckia fluminensis), T4 (C3 - Azotobacter vinelandii), T5 (Control) and T6 (fertilization). From the results it was observed that there was a great variability of rhizosphere microorganisms resulting in five bacterial genera Rhizobium, Azotobacter, Stenotrophomonas, Sphingomonas and Beijerinckia. In the quantification analysis and production of indole acetic acid (IAA), 100% of the bacterial isolates were able to produce (AIA), while none of the strains tested were capable of solubilizing inorganic phosphorus. In the evaluations pertaining to the morphological parameters, plant height and number of leaves at 30, 60, and 90 days following sowing (DAS) and parameters of biomass (PFR, PFF, PSR and PSF), the best results obtained were with the T4 (C3-Azotobacter vinelandii) treatment.