Özet:

Repellent, ovicidal and oviposition deterrent effects of six plant extracts (Heracleum platytaenium Boiss (Apiaceae), Humulus lupulus L. (Cannabaceae), Achillea millefolium L. (Asteraceae), Acanthus dioscoridis L. (Acanthaceae), Phlomoides tuberosa (L.) Moench (Lamiaceae), Bifora radians Bieb. (Apiaceae)) were tested on Leptinotarsa decemlineata Say, 1824 (Coleoptera: Chrysomelidae) under laboratory conditions. Methanol extracts prepared from plant vegetative components were tested on L. decemlineata. Heracleum platytaenium extract was significantly more toxic against the egg stage than all other extracts, except for A. millefolium 5 d after treatment. It was followed by A. millefolium extract reducing the egg hatch rate to 15%. Significant mortality was not observed in the case of other plant extracts. In the second series of experiments, different dose-response bioassays with H. platytaenium against L. decemlineata eggs were conducted. The lowest egg hatch rate of 1% was observed at 7.5% [w/v (plant extract/acetone]. The greatest oviposition deterrent effect was seen with the H. platytaenium extract treatment, which resulted in no egg laying. Plant extracts showed a high level of repellent activity to L. decemlineata and their activity increased with extended incubation time. The greatest repellency was observed with the A. millefolium extract treatment, which gave 0.01% repellency in the first 15 min. These results show that H. platytaenium extract could be a useful toll in the control of L. decemlineata.

Anahtar Kelimeler: