Evaluación de la actividad insecticida de extracto acuoso y alcohólico de Ruda (Ruta graveolens), Marco (Ambrosia arborescens Mill.), Chilca (Baccharis latifolia), Romero (Rosmarinus officinalis), utilizados para controlar el pulgón (Brevicoryne brassicae) en cultivo de col (Brassica olerasia var capitata) en Riobamba.

Abstract

The objective was to evaluate the insecticidal activity of the aqueous and alcoholic extracts of Ruda (Ruta graveolens), Marco (Ambrosia arborescens), Chilca (Baccharis latifolia), Romero (Rosmarinus officinalis) used to control the aphid (Brevicoryne brassicae) in crops of cabbage (Brassica oleracea var. capitata). The vegetal material was gathered in Riobamba canton at 2764 m.a.s.l, from Chimborazo province. The conditioning was carried out in the laboratories of the Escuela Superior Politécnica de Chimborazo and field. The extraction of extracts were obtained by cooking and maceration (alcoholic) and was dried in a rotavapor at 40 °C. From those extracts, the insecticide activity was determined through the experimental method using the mixture of extracts from the four (4) plants in equal fractions of aqueous and alcoholic extract at different concentrations; 10%, 15% and 20%, and we gauged with non-chlorinated water. The insecticide activity was determined by adding the extracts to the plant, triplicate tests. It was observed that at 45 days there was already an increment of the aphids’ population in the cabbage. It was possible to determine that the one with the best insecticidal activity was the CHLORPYRIFOS and of the extracts were the T1 (10% alcoholic extract) from the fourth application until the seventh (7) application due to they presented a higher activity than the other treatments. The T2 (Witness) was the one that showed the highest growth in the population of aphids. Therefore, the insecticide of the mixture of (Ruda, Marco, Chilca and Romero) in the alcoholic extract at 10% is considered the best treatment. And due to its easy degradation is not harmful to the health of consumers, emulsifiers must be used to improve the dissolution of metabolites in alcoholic extracts, and the appearance of the product changes so much the smell, taste, and aroma are more pleasant to taste.