Caracterización de bacterias endófitas de raíces de Macleania rupestris para la identificación de cepas promotoras de crecimiento vegetal

Abstract

The soil harbors a large number of microorganisms, which can establish symbiotic relationships, well known between microorganisms and plants, however, little is known about the interactions between Macleania rupestris and the microorganisms associated with it. M. rupestris, locally known as "joyapa" is a native species belonging to the family Ericaceae, which presents an edible berry of great ecological importance. In order to identify cultivable plant growth-promoting microorganisms, bacteria were isolated from joyapa roots and the ability of the isolates to solubilize phosphates and produce Indole Acetic Acid (IAA) was evaluated under in vitro conditions. Twelve of the 20 bacterial isolates showed phosphate solubilization halos when seeded on NBRIP medium and none showed AIA production when evaluated by staining with Kovacs reagent. The strains that showed positive results for the phosphate solubilization test were inoculated on joyapa seedlings to evaluate their effect on development. After 12 weeks, plant growth (final size minus initial size), number of leaves, root length and dry weight were recorded. The results showed statistically significant differences in 8 strains for the growth variable, in dry weight 5, and 3 strains for the root length variable, surpassing the control in both cases. The results show the ability of bacterial isolates associated with M. rupestris to solubilize phosphates under in vitro conditions and show the positive effects that some of them have on the plant development of this species