Actividad insecticida de una emulsión aceite/agua del aceite esencial de Eucalyptus tereticornis

Introduccion: el aceite esencial extraido de especies del genero Eucalyptus, entre estas Eucalyptus tereticornis, ofrece un importante potencial para el control de hongos patogenos e insectos plaga y de importancia medica. Objetivo: evaluar la actividad anti-insecto (aguda, cronica y repelente) de una emulsion aceite/agua del aceite esencial de Eucalyptus tereticornis, en funcion de su composicion quimica y fraccionamiento. Metodos: se prepararon emulsiones aceite/agua con aceite esencial previamente extraido, separado y caracterizado, y 2 de sus fracciones (A y B). Se evaluo su actividad anti-insecto mediante bioensayos con Drosophila melanogaster. Se determino la fitotoxicidad foliar sobre plantulas de Phaseolus vulgaris. Resultados: el aceite completo mostro considerable actividad repelente e insecticida aguda que guarda relacion con su composicion quimica. La actividad insecticida aguda de las fracciones disminuyo de manera notable con respecto a la mostrada por el aceite completo, sin embargo, no se observaron efectos significativos sobre la actividad repelente. En ningun caso se presento fitotoxicidad foliar sobre frijol. Conclusion: el aceite esencial de esta especie de eucalipto posee actividad anti-insecto considerable y podria formularse directamente como insecticida para el control de insectos de interes agricola y medico. Introduction: the essential oil extracted from Eucalyptus species, including Eucalyptus tereticornis, offers significant potential for control of fungal pathogens and insect pests and medical importance. Objectives: to evaluate the anti-insect activity (acute, chronic and repellent) of an oil/water emulsion of Eucalyptus tereticornis essential oil in terms of their chemical composition. Methods: oil/water emulsion was prepared with essential oil previously extracted, separated and characterized, and two of its fractions (A and B). Their anti-insect activity was evaluated through bioassays on Drosophila melanogaster. Foliar phytotoxicity was evaluated on seedlings of Phaseolus vulgaris. Results: the complete oil showed considerable acute repellent and insecticide activity related to its chemical composition. The acute insecticidal activity of the fractions decreased significantly if compare with that of the whole oil , but neither significant effects on the repellent activity nor phytotoxicity on the bean leaves were observed. Conclusions: the essential oil of this eucalyptus species has considerable anti-insect properties and could be formulated as an insecticide for the control of insects of agricultural and medical significance.