Resumen

Terpenes are found in abundance in all plant essential oils. In the present study two pure volatile compounds of terpene group, a-pinene and b-caryophyllene have been evaluated for their repellent, acute toxicity and developmental inhibitory activities alone and in binary combination against red flour beetle Tribolium castaneum. In repellency assay, a-pinene and b-caryophyllene repelled T. castaneum adults significantly even at 0.025% concentrations. Fumigation of larvae and adults of T. castaneum with these two compounds caused lethality in them. Median lethal concentrations (LC⁵⁰) of a-pinene and b-caryophyllene against adults were 0.998 and 1.624 bl/cm³ and against larvae were 1.379 and 1.949 ml/cm³ respectively. In binary combination, the LC₅₀ values against adults and larvae were found 1.277 and 1.438 ml/cm3 respectively. Fumigation with two sublethal concentrations viz. 40 and 80% of 24-h LC⁵⁰ of these two compunds alone and in binary combination significantly reduced oviposition potential of adults and inhibited pupation and adult emergence in larvae. All the responses were found concentration-dependent. From the present study, it can be concluded that a-pinene is more active than b-caryophyllene and these two volatile compounds in binary combination shows synergism and thus, can used as efficient insecticidal tool against T. castaneum as fumigant either alone or in combination.

Palabras clave: a-Pinene b-Caryophyllene Tribolium castaneum fumigant toxicity terpenes.

2012-06-29   |   809 visitas   |   Evalua este artículo 0 valoraciones

Vol. 4 Núm.1. Junio 2012 Pags. 53-62 Ecologia Balkanica 2012; 4(1)