A COMPARISON BETWEEN ACARICIDAL ACTIVITY OF THREE ESSENTIAL OILS FROM Ocimum basilicum, Coriandrum sativum Y Thymus vulgaris AND Tetranychus urticae

Ecuador is the third largest exporter of flowers in the world; their diversity and quality are internationally renowned and they are a major contribution to the country's economy. However, this industry is threatened by numerous pests; one of the most harmful being the acarus known as "red spider mite" or Tetranychus urticae. Dangerous, synthetic pesticides are used in order to control this mite. Our research was carried out in the flower farm of "La Juliana" (north Andean zone of Ecuador, 00 degrees 03'00 '' N and 78 degrees 12'00 '', 2840 mamsl). Its objective was to evaluate the acaricidal properties of three essential oils: coriander (Coriandrum sativum), basil (Ocimum basilicum), and thyme (Thymus vulgaris), against the Tetranychus urticae mite. The effects of the acaricide test were measured 24 and 48 hours after applying the essential oils, and the results were compared through non-parametric analysis. The effective concentration for Ocimum basilicum was of 1.60%, for Thymus vulgaris was of 1.60% and for Coriandrum sativum, 3.12%. Furthermore, each concentration was compared to the research control "ethanol" group and a synthetic pesticide mixture used regularly by the flower farm technicians. After 24 hours, the thyme essential oil showed the best acaricidal effects, after 24 and 48 hours high effectiveness was observed for the thyme and basil essential oils. Finally, a natural product was formulated whose active ingredient was the thyme essential oil and compared to the Abamectin-Tetradifon synthetic blend, showing a similar acaricidal effect.