Actividad insecticida de extractos liquénicos de Physcia sp. en larvas de Tecia solanivara Insecticidal activity of lichen extracts from Physcia sp.in Tecia solanivara larvae

Abstract

Los extractos obtenidos con solventes de diferente polaridad (eter de petroleo (EEP), acetona (EA) y metanol (EM)) de Physcia aipolia, fueron evaluados como posibles sustancias insecticidas frente a larvas de Tecia solanivara, la mayor plaga que enfrenta el cultivo de la papa. Para realizar el estudio, se utilizo la tecnica de exposicion a superficies tratadas con insecticidas formulados. Se prepararon ocho diferentes concentraciones de las sustancias a ensayar comprendidas entre 5,0x104 y 5,0x10-10 μg/mL, la mortalidad de las larvas se registro transcurridas 24 horas de la aplicacion de los mismos. Los resultados revelaron actividad insecticida en EA a partir de 5,0x10-6 μg/mL, en EEP a 5,0 x10-2 μg /mL, y EM a 5,0 x102 μg/mL. El analisis de los datos detecto diferencias estadisticamente significativas entre los tratamientos evaluados con el testigo por debajo de 5,0 μg /mL. Los datos obtenidos representan una contribucion en el campo de los productos naturales puesto que hasta la fecha no se han encontrado estudios que reporten actividad larvicida en Tecia solanivora utilizando extractos del genero ni de la especie. Palabras claves: Insecticida, liquen, Physcia, Tecia solanivora. Abstract The extracts obtained with solvents of different polarity (petroleum ether (EEP), acetone (EA) and methanol (EM)) of Physcia aipolia, were evaluated as possible insecticidal substances against larvae of Tecia solanivara, the largest pest facing the crop of the potato. To carry out the study, the technique of exposure to surfaces treated with formulated insecticides was used. The substances to be tested were prepared at eight different concentrations ranging from 5.0x10-4 to 5.0x10-10 μg / mL, larval mortality was recorded 24 hours after application of the substances. The results showed insecticidal activity in EA from 5.0 x 10-6 μg / mL, in EEP at 5.0 x 10-2 μg / mL, and EM at 5.0 x 10 2 μg / mL. The analysis of the data detected statistically significant differences between the treatments evaluated in relation to the control. The data obtained represent a contribution in the field of natural products since to date no studies have been found that report larvicidal activity in Tecia solanivora using extracts of the genus or of the species. Keywords: Insecticide, lichen, Physcia, Tecia solanivara.