In this study, we tested 14 plants from the native spontaneous flora to highlight the potential effects of repellents and insecticides on Colorado potato beetle (Leptinotarsa decemlineata Say). Of all the plants tested, only three of them had a good potential to determine an increased mortality (%) of adults and larvae of the species Leptinotarsa decemlineata Say after 168 h, in the order: Primula veris, Origanum vulgare and Achillea millefolium. The highest mortality (%) was observed after treatments with crude alcoholic extracts of Primula veris obtained by the method of extraction based on hot reflux (HAE) in the Soxhlet equipment, 90% in the case of larvae and 80% in adults, respectively. In order to make more efficient the extraction process, respectively to reduce the amount of solvent used as well as the extraction time, we tested another conventional technique, such as maceration (M) and one from the category of "environmentally friendly", ultrasound-assisted extraction (UAE), respectively. We also tried a combined technique: ultrasound-assisted extraction followed by maceration (UAE+M). The highest extraction degree (%) using UAE+M was achieved by the species Origanum vulgare which indicated 70% mortality in the case of adults, after 168h. Our results indicate that spontaneous flora could be successfuly used in combating the adults and larvae of Leptinotarsa decemlineata Say.

biopesticides, heat assisted extraction, Leptinotarsa decemlineata Say, Primula veris, ultrasound assisted extraction, vegetal extracts

biology

Presentation: None