Antifeedant activity and growth inhibition effects of Achillea millefolium L. (Asteraceae), Heracleum platytaenium Boiss (Apiaceae), and Humulus lupulus L. (Cannabaceae) extracts were tested on the third instar larvae of Colorado potato beetle (Leptinotarsa decemlineata Say, Col: Chyrsomelidae) under laboratory conditions. Plant extracts were obtained treating "cones" of H. lupulus, leaves and stems of H. platytaenium and leaves, stems and flowers of A. millefolium with methanol using maceration technique. The plant extracts (50 g/L) were applied to potato leaflets and consumption area for individual insect was measure with a planimeter after 24, 48 and 72h. The single dose screening bioassay revealed that all tested plant extracts possessed antifeedant activity against the beetle larvae at 50 g/L concentration and average consumed leaf area were 0.04 cm 2 , 0.05 cm 2 and 0.30 cm 2 for H. lupulus, H. platytaenium and A. millefolium respectively. In dose response bioassay, it was revealed that there was a negative correlation between the averages consumed leaflet area and the plant extract dose. The greatest antifeedant activity was seen in H. lupulus extract treated leaflets at 10 g/L concentration and the average consumed leaflet area was 0.68 cm 2 after 72 h. The H. platytaenium and H. lupulus extracts had similar effects on the larval growth indices. Both plants extracts had 1.2 growth index values at 30 g/L concentration. These results indicate that the H. platytaenium and H. lupulus extracts could have significant potential as antifeedant and larval growth inhibition agent in the control of larvae of Colorado potato beetle.

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Chemical composition and insecticidal potential of different Origanum spp. (Lamiaceae) essential oils against four stored product pests Farklı Origanum spp. (Lamiaceae) uçucu yağlarının kimyasal kompozisyonu ve dört depolanmış ürün zararlısına karşı insektisidal potansiyeli

Discovery of new eco-friendly methods for insect pest management is very important in integrated pest management program. Contact toxicity of six plant extracts i.e. Acanthus dioscoridis L. (Acanthaceae), Achillea millefolium L. (Asteraceae), Bifora radians Bieb. (Apiaceae), Heracleum platytaenium Boiss (Apiaceae), Humulus lupulus L. (Cannabaceae) and Phlomoides tuberosa (L.) Moench (Lamiaceae), were tested on the 1 st to 4 th instar larvae of Colorado potato beetle (Leptinotarsa decemlineata Say. (Coleoptera: Chrysomelidae)). The H. platytaenium and H. lupulus extracts were the most effective among the tested extracts, so dose-response bioassay was carried out only with H. lupulus and H. platytaenium against larval stages of Colorado potato beetle. The H. platytaenium extract was the most effective extract with calculated LD 50 values 0.126, 0.204, 0.206 and 0.458 μL insect-1 , LD 90 values were calculated as 0.345, 0.342, 0.402, 0.566 μL insect-1 for 1 st , 2 nd , 3 rd and 4 th instars larvae respectively. These results indicate that H. platytaenium and H. lupulus extracts have great potentials as insecticides in the management of larvae of L. decemlineata.

In this study, it was investigated that repellency and insecticidal efficacy of trans-anethole of botanical origin on major stored product on pests species, namely Sitophilus granarius (L.) (Coleoptera: Curculionidae), Sitophilus oryzae (L.) (Coleoptera: Curculionidae), Tribolium confusum Jacquelin du Val (Coleoptera, Tenebrionidae) and Tribolium castaneum (Herbst) (Coleoptera, Tenebrionidae). Repellency effect was evaluated by choice test in petri dishes, while the mortality effect was examined by exposure to wheat treated at different concentrations, such as 1, 2, 3, 4, and 8 µL trans anethole. In efficacy tests, after 72 hours exposure, the highest adult mortality was found on T. castaneum with a 60% mortality, while other test species showed no significant mortality. On the other hand, repellency tests revealed varying degree of repellency depending on the application dose of trans-anethole. It was determined that S. granarius belongs to repellent class III, while all of the other species fall under repellent class IV. F1 progeny decreased as trans-anethole concentration increased, and in this context 8 µL of trans-anethole is proved to be the optimal concentration causing maximum decrease in progeny production. Among the insect species tested, T. confusum was found to be the most sensitive to transanethole with 100% decrease in F1 progeny production. Our results indicate that trans-anethole can be used as a potential repellent for the control of major stored grain pests. Additionally, trans-anethole, by its contact efficacy, might be considered as a grain protectant against S. granarius, S. oryzae, T. confusum and T. castaneum.