Identificación de microorganismos presentes en el suelo de páramo bajo tres tipos de vegetación en Tisaleo, Tungurahua

Abstract

Some inhabitants of the Tisaleo town carry out grazing and livestock raising activities, which generates a loss in the diversity of vegetation species and microorganisms. This study aimed to identify microorganisms present in the moorland soil of the Tisaleo town under three types of vegetation: cushion, shrubby and herbaceous. The research developed was experimental, with a Completely Randomized Design (CRD), in which three types of soils were considered based on their vegetation cover, with five concentrations (10-1, 10-2, 10-3, 10-4, 10-5) and three repetitions. For this purpose, 1 kg samples were collected of soil taken at 10 cm under the three types of vegetation cover, each composed of 50 subsamples. Microorganisms were isolated through serial dilutions. For the identification of fungi and bacteria, a culture medium containing Potato Dextrose Agar (PDA) without antibiotics was prepared. Subsequently, the morphotypes of the microorganisms found were identified through cultural and morphological characterization. Colony Forming Units (CFU) were quantified per ml or gram sample after eight days of inoculation. According to the results, there was a predominance of bacteria (99.44% of the total) and a small proportion of fungi (0.56%). The morphotypes of bacteria were smooth bright yellow colony (44.62% of the total), flat irregular cream colony (39.33%) and other colonies that individually represented less than 5%. For its part, the fungal species found were Aspergillus sp. (50% of the total), Purpureocillium sp. (18.1%), Bauveria bassiana (16.55%), Aspergillus niger (12.5%) and Penicillium sp (2.85%). In conclusion, the soils under herbaceous vegetation were the ones that presented the greatest biological diversity due to having a greater number of colonies of bacteria and fungi, followed by the soils under shrub vegetation, and finally those under cushion vegetation.