Eficiencia degradativa de tres especies de hongos benéficos Aspergillus Niger, Thichoderma Harzianum y Paecilomyces Lilacinus sobre suelos contaminados con petróleo en la parroquia San Carlos del cantón Joya de los Sachas.

Abstract

The objective of this research was to determine the degrading efficiency of three beneficial fungus species on oil contaminated soils in San Carlos parish, Joya de los Sachas Cantón. The research was carried out in the Biological Sciences Laboratories of the Faculty of Natural Resources of Escuela Superior Politécnica de Chimborazo with the use of 3 species of fungi (Aspergillus niger, Thichoderma Harzianum and Paecilomyces lilacinus), 2 culture media Potato Dextrosa Agar (PDA) and contaminated soil (CS), 3 concentrations ((10

xviii 7 , 10 8 , y 10 9 ), and 3 replicates (R1, R2, R3) giving a total of 54 experimental units. It was compared its development expressed in colonies diameters (cm ) carried out in 54 petris boxes with the use of Sterilized Soil and Non- Sterilized Soil. It achieved a greater growth of the species of fungi with the use of Sterilized Soil. As results obtained from the degradation efficiency with the three fungal species, 37.65% were obtained for Aspergillus niger, 32,76% for Thichoderma harzianum and 29,59% for Paecilomyces lilacinus. The process developed by applying the three benefical fungal species shows a 100% efficiency in the hydrocarbon degradation by reducing their initial concentration of 5080 ppm to values <1000 ppm, which is why the three species of fungi are highly effective in degradation of hydrocarbons generating in the inhabitants of the zone a social, economic and environmental benefit. Concluding that numerically Aspergillus niger, is more efficient than Thichoderma harzianum and Paecilomyces lilacinus. For future research on soils contaminated with oil by the use of microorganisms is recommended to perform with different species of fungi to know their different effectiveness.