Efeito de óleos essenciais de espécies aromáticas que ocorrem no bioma de Pernambuco sobre o Ácaro Rajado (Tetranychus urticae)

Abstract

This study inquiry the chemical composition of essential oil of Croton jacobinensis, C. micans, C. rhamnifolius, C. muscicapa, C. pulegioides, C. rhamnifolius var. helliotropiifolius, Eugenia uvalha, C. sellowii species as well as evaluates the acaricide potential of C. jacobinensis, C. micans, C. rhamnifolius, C. muscicapa, E. uvalha and C. sellowii species. The major chemical constituents identified in essential oils obtained of diverse tissues from the Croton species were: (Z)-α-atlantone (24.3%, leaves, C. jacobinensis),Trans-isolongifolanone (22.8%, stem, C. jacobinensis ), α-bulnesene (32.9%, leaves, C. micans), guaiol (17.9%, stem, C. micans), α-Cedrene epoxide (23.3%, leaves, C. rhamnifolius), camphor (16.6%, stem, C. rhamnifolius), foeniculin (50.6%, leaves, and 72.7%, stem, C. muscicapa), 1.8-cineole (15.56%, leaves, C. pulegioides ), α-calacoreno (12.95%, stem, C. pulegioides), β-caryophyllene (20.82%, leaves, C. rhamnifolius var. helliotropiifolius) and guaiol (18.38%, stem, C. rhamnifolius var. helliotropiifolius). It were identified the compounds β-caryophyllene (24.3%) and (33.6%) of essential oils from leaves and flowers of E. uvalha, respectively, and caryophyllene oxide (42.4%) constituent of its stems. The major component identified on C. sellowii was β-caryophyllene (33.5%, 20.9% and 41.2%) in the leaves, stem and flowers, respectively. The essential oils showed acaricidal activity against Tetranychus urticae. The better response for fumigation activity was founding for the leaves of E. uvalha and stem of C. rhaminifolius (both LC50 of 0.20 μL / L air), followed by oil from stem of C. jacobinensis (LC50 = 0.30 μL / L air). For the best patch test result was reported from the oil of the stem of C. sellowii (LC50 = 0.53 mL / mL). While for the test repellent essential oil from leaves of C. sellowii showed a better result with a RC50 of 0.009 μL/cm2. For the dual-choice test, both oils tested showed a preference for the mites to go untreated until 24 hours drive of exposure and a preference to oviposit in untreated hard even after 48 hours of experiment. With these results all oils evaluated had the potential to be used in the integrated management of the mite.