Aislamiento y caracterización de microorganismos entomopatógenos en dos sistemas de producción agrícola familiar representativos de la comunidad Gaushi.

Abstract

This research aimed to isolate and characterize entomopathogenic microorganisms from two family farming systems (organic-conventional) in Gaushi community. Composite soil samples were taken using the L-sampling technique. The "bait-insect" method proposed by Zimmermann, 1986 adapted by Meyling, 2007 was applied for the induced infection getting 19 fungal and 10 bacterial isolates with entomopathogenic characteristics from a total of 173 isolates. For statistical analysis, a bifactorial Complete Randomized Design DCA was applied. Mortality tests were carried out with suspensions of 10 to seven bacteria/ml and spores/ml for 5 and 14 days respectively to select the most effective isolates. For the lethal dose (LD) 50 and TL 50, concentrations ranging from 10^6,10^7,10^8 and 10^9 spores/ml were used, and Probit was used for statistical analysis. For effective isolates, morphological and molecular characterization was performed. The most effective isolates showed a 100% mortality on the fifth day and these were GSCC3R2-A1 with a LD50 of 1.87 x 10 at eight spores/ml and GSOC2R2-A1 with a LD50 of 5.34 x 10 at eight spores/ml corresponding to Beauveria bassiana, GSCC2R2-A5 with an LD50 of 4.44 x 10 at eight spores/ml and GSOC3R2-A3 with an LD50 of 3.09 x 10 at eight spores/ml corresponding to Metarhizium anisopliae. These species could be confirmed by molecular analysis. It is concluded that in the family agricultural production systems of this community there is the presence of entomopathogenic microorganisms, and these are considered as a local alternative for the biological control against the attack of pests reducing the agricultural productivity of the area, therefore, it is recommended to include the isolates of greater effectiveness obtained in the elaboration of bio inputs.