Determinación de la Concentración Letal 50 (cl50) en la Lombriz Californiana, Eisenia Foetida (Lombricidae) de Dos Fungicidas de Uso Agrícola con el mismo Principio Activo (Difenoconazol)

Abstract

Through acute toxicity tests are evaluated the CL50 of the fungicide Difenoconazole 250 EC in the californian red worm (Eisenia foetida), which is widely used in the field of agriculture to control diseases in cereal crops, vegetables, vegetables, among others; where your application can cause effects on organisms not targets. To carry out the study was taken as reference the methodology of the EPA (OPPTS 850.6200), with a completely randomized experimental design, in which there was a control and five concentrations for each fungicide, each with 4 replicas, for a total of 44 experimental units, with 10 individuals each. The experimental units were made up of PET containers with a volumetric capacity of 1 liter, which contained 500 g of soil from a tomato crop Gaunza in the village of the municipality of Guateque, Boyacá; this container was covered with linen cloth to avoid direct contact with the light and the exchange of oxygen. For both the preensayo as for the bioassay was calculated the water retention capacity of the soil, to obtain a percentage moisture content of 70%. For the concentrations used in the preensayo was taken as the basis of a technical opinion and in this way obtain a reference concentration for the final trial. Then, it was determined the final concentrations (0,04, 0,128, 0,217, 0,306 y 0,395 0,5 ), once the monitoring was completed, the lethal concentration 50 of the two pesticides was determined, obtaining a concentration of 0.3911 0,5 for the pesticide 1, while for the 2 0,3647 0,5 To verify that the physico-chemical parameters do not affect the mortality of the worms there was a correlation between these variables getting that there is no relationship between them. On the other hand, we calculated the area under the curve for all replicas, and an analysis of variance 2 concluding that the pesticide is more toxic than the pesticide 1, because it requires less concentration to get to the same mortality and weight in the pesticide 2 is most affected at lower concentrations.