Poljoprivreda (Jun 2011)
INSECTICIDAL TOXICITY OF 1,8-CINEOLE, CAMPHOR AND EUGENOL ON TRIBOLIUM CASTANEUM (HERBST)
Abstract
Contact and fumigant activity of 1,8-cineole, camphor and eugenol compounds were tested In laboratory conditions on adult, larvae and pupae of the red flour beetle Tribolium castaneum (Herbst), as well as their effect on progeny emergence. Positive results were obtained with contact application for all three tested compounds and on all three stages of development of T. castaneum, with the highest activity of 1,8-cineole, followed by eugenol and camphor. Ingeneral, fumigant activity of all three compounds was lower in comparison to contact application, with the best activity of 1,8-cineole, followed by camphor and eugenol on all three developmental stages of T. castaneum. However, lower activity was recorded for fumigation of the space 50% filled with wheat grain for all three tested compounds on all three stages, with the best activity of 1,8-cineole, followed by camphor and eugenol, whereas eugenol showed no toxicity to the adult stage. The activity of 1,8-cineole and eugenol in the space 50% filled with wheat grain decreased by 3.5 and 32 times, respectively, whereas the activity of camphor had no significant difference on the larvae. Toxicity of the tested compounds on pupae T. castaneum was either lethal or directly affected to metamorphosis pupae. There were significant differences observed in the efficacy of the tested compounds on the gender of the pupae, with the most markedly differences for 1,8-cineole, followed by camphor and the minimal for eugenol. Males were more sensitive to the applied compounds, whereas females had more deformed units, especially in the fumigation treatment with camphor. The most tolerant stage on the contact and fumigant application of all compounds was the pupae stage. Eugenol and 1,8-cineole had influence on the reduction of T. castaneum progeny emergence, whereas camphor had no such effect. Due to a high potential of 1,8-cineole for the control of the red flour beetle Tribolium castaneum (Herbst) (at all treatments, for all the tested stages of development), camphor for the fumigant control of adult (in the empty storages), as well as of eugenol for contact control (all developmental stages) and for fumigant application (for the reduction of progeny), these compounds represent a valuable basis for creating new active substances as an alternative to the conventional pest control products.
