AISLAMIENTO DE BACTERIAS (FNVL Y SF) EN UN HAPLARGIDS VENEZOLANO

Abstract

In order to evaluate their potential to be used as biofertilizers, through a greenhouse bioassay with tomato seedlings, free-living Nitrogen-fixing (FNVL) and Phosphorus-solubilizing (SF) bacterial strains were selected from the rhizosphere of three types of land use in the “El Cebollal” sector of the Miranda municipality of Falcón state, soil samples were collected in the different types of land use (TUT) such as: Aloe vera under organic management (TUT1), Melon conventionally managed (TUT2) and the natural forest of the area (TUT3), which were processed for the isolation and selection of the strains in the Biofertilizers laboratory of the INIA-Maracay. TUT2 and TUT3 have affected the populations of FNVL bacteria, which is due to the fact that in TUT2 the salinity is high due to the excessive use of chemical fertilizers and water with a high saline content, in TUT3 the organic matter content is high. but with a moderate saline content compared to TUT1 in which greater development of the strains was obtained, as well as, the pH may be inhibiting solubilization, which may be affecting the levels of bacterial biomass, however the SF populations , were less affected by the adverse conditions of the environment, in addition they presented optimal development and excellent potential for the production of biofertilizers, according to the results obtained in the bioassay, where the variables: length of the roots of the seedlings and number of plants with the appearance of the first true leaf at seven days, showed highly significant differences, therefore we conclude that the FNVL strain from TUT1 and all the SF strains evaluated, have the potential to stimulate plant growth, fix Nitrogen and solubilize Phosphorus, therefore both can be selected to be used as biofertilizers