Efecto acaricida y ovicida de los aceites esenciales de Chenopodium ambrosioides L. y Peperomia inaequalifolia Ruiz & Pav. contra Tetranychus urticae en fresa (Fragaria spp.)

Abstract

The present study evaluated the acaricidal effect of the essential oils from Chenopodium ambrosioides L. and Peperomia inaequalifolia Ruiz & Pav. on eggs and adult females of Tetranychus urticae in strawberry plants (Fragaria spp). Essential oils were obtained by steam distillation and analyzed by gas chromatography-mass spectrometry (GC/MS). The oils and their mixtures were diluted in dimethyl sulfoxide (DMSO) at concentrations ranging from 0.5% to 4% for ovicidal tests, between 2.5% to 0.125% for acaricidal tests. The various solutions were put in contact with with T. urticae eggs to assess their viability and with adult mite females of the mite to determine the CL50, in treatments distributed in a completely randomized desing. Tetradifon (ovicidal) and abamectin (acaricidal) were used as positive controls, and DMSO as the negative control. The chemistry of the oils showed the most abundant molecules in C. ambrosioides were sylvestrene (18.68%), trans-p-Mentha-2,8-dienol (18.06%), trans-p-mentha-1(7),8-dien-2-ol (11.75%) and cis-p-mentha-1(7),8-dien-2-ol (11.74%); while in P. inaequalifolia, elemicin (36.33%) and myristicin (20.21%) were predominant. The essential oils were efficient in inhibiting the development of mite eggs. The tests on adult females show diverse behaviors in essential oils, where lethality is higher in P. inaequalifolia and lower with C. ambrosioides. In general, a significant activity of the oils and their mixtures as ovicides, and P. inaequalifolia as an oil with acaricidal potential was observed.