Evaluación de aceites esenciales de tomillo (Thymus vulgaris) y menta (Mentha x piperita) en el control de ácaros asociados al cultivo de fresa (Fragaria × ananassa) en condiciones in vitro

Abstract

The purpose of this degree research was to evaluate the acaricidal potential of thyme (Thymus vulgaris) and peppermint (Mentha x piperita) essential oils, applied individually or in combination, as a sustainable alternative for the control of Tetranychus urticae, a phytophagous mite with high incidence in strawberry (Fragaria x ananassa) crops under in vitro conditions. Conventional management of this pests relies mainly on the use of synthetic acaricides. The challenge in controlling T. urticae is associated with its high adaptive capacity of resistance to synthetic acaricides, as well as, the negative impacts derived from the intensive use of these products on the environment, human health and beneficial organisms. The evaluation was conducted through direct contact bioassays using the leafdisc method, which adult mites to bean leaf disc (Phaseolus vulgaris) previously treated with different concentrations (0%, 0,5% y 1%) of essential oils, allowing controlled simulation of the pest-plant surface interaction. The experiment was arranged in s completely randomized designs with a 3x3 factorial structure, including negative control and chemical control. Mortality was recorded at 24 and 48 hours after application, corrected using Abott’s formula and statistically analyzed by ANOVA followed by Tukey’s mean comparisons test (p <0,05). The results showed the statistically significant differences among treatments, with thyme essential oil exhibiting the highest mortality rates, both individual or in combination with peppermint, reaching values comparable to the chemical control. Additionally, visible morphological alterations were observed in mites treated with essential oils, including changes in coloration, loss of turgidity, and body deformations, suggesting a mechanism of action associated with the physiological toxicity of the evaluated compounds.