Depolanmış ürünlerdeki böceklerle mücadele oldukça önemlidir. Sitophilus granarius (Linnaeus, 1758) (Coleoptera: Curculionidae) ve Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidea) depolanmış ürünlerde zarar meydana getiren önemli iki zararlı böcek türüdür. Depolanmış ürünlerdeki zararlılarla mücadelede kullanılabilecek alternatif ilaçlara ise her geçen gün ihtiyaç artmaktadır. Bu çalışmada, Achillea phrygia Boiss. et Bal. (Compositae), Prangos ferulacea (L.) Lindl. (Apiaceae) ve Salvia wiedemannii Boiss. (Lamiaceae) bitkilerinden elde edilen bitki ekstraktlarının, S. granarius ve T. castaneum ile mücadelede kullanılabilirlikleri araştırılmıştır. 72 saat sonunda, S. garanarius üzerinde test edilen bitkiler arasında en yüksek kontak aktiviteyi sırasıyla %74 ile P. ferulaceae hekzan, %71 ile A. phrygia methanol ekstraktı göstermiştir. T. castaneum üzerinde en yüksek aktiviteyi ise 72 saat sonunda %42 ile A. phrygia etil asetat ekstraktı göstermiştir. Bitki ekstraktları ile yapılan davranışsal etki çalışmalarında ise S. granarius üzerindeki en yüksek repellent aktivite 24. saat sonunda P. ferulaceae etil asetat ekstraktından (%52) elde edilmiştir. Bitki ekstraktlarının tamamı T. castaneum üzerinde yüksek oranda repellent etki göstermiştir.

In the scope of this study, we have investigated fumigant and contact toxicity effects of Satureja boissieri Hausskn. ex Boiss. essential oil against Sitophilus granarius L. (Coleoptera: Curculionidae) and Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae). The fumigant and contact toxicity experiments were carried out with the adults of Sitophilus granarius whereas the contact toxicity experiment was carried out with the 3rd, 4th and 5th larvae of S. littoralis. Also, various fractions of S. boissieri essential oil were investigated for fumigant activity against S. granarius. In fumigant toxicity studies, the highest activity was obtained at 36 hours with a dose of 0.1 μl/ml with a 100% mortality rate. Fractions of the essential oil had significant fumigant activity on S. granarius (100% fumigant activity at 0.1 μl/ml). Contact toxicity of 100 μl/ml essential oil on the 3rd and 4th larval stage of S. littoralis, was determined to be 100%, however, on the 5th larval stage it was 90.17%. The activity at 25 μl/ml dose was 71.12% in the 3rd larval stage whereas the activity remained very low (6.39- 22.20%) in other larval stages. These results indicated that essential oil of S. boissieri have significant potential which merits to be studied further in possible applications as fumigant and contact insecticide in the control of S. granarius and S. littoralis.

The essential oil composition of aerial parts of Ruta chalepensis L. was analyzed with GC-MS. Seventy-nine compounds were detected representing 85.93 ± 1.08% (n = 3) of the essential oil. The major components of the essential oil were 2-undecanone 21.52 ± 0.21%, 2-nonanone 18.31 ± 0.27%, and 2-nonyl acetate 13.22%. The highest insecticidal contact toxicity of the oil was observed against Rhyzopertha dominica F. with 0.018 μl/insect LD50 and 0.039 μl/insect LD90 after 24h. Essential oil also produced considerably low 0.50 and 0.59 μl/insect LD50 values after 24h against Sitophilus oryzae L. and Sitophilus granarius L. respectively. The lowest contact toxicity was observed against Tribolium castaneum Herbst. and Tribolium confusum Jacquelin du Val. 0.138 and 0.078 μl/insect LD50 after 24h respectively. The highest fumigant toxicity was observed against S. granarius for the application concentration of 10 μl, 10% oil/acetone (v:v) in a 10 ml chamber which afforded 100.00 ± 0.00% mortality after 48h. The essential oil also produced high fumigant toxicity against S. oryzae, T. castaneum and R. dominica which were 95.47 ± 3.41%, 93.30 ± 5.54%, and 85.47 ± 3.41% mortality at 20 μl application concentration of the oil solution after 48h. The R. chalepensis essential oil produced low acetylcholinesterase enzyme 5.29 ± 1.20% (n=3) inhibition and mediocre butyrylcholinesterase enzyme inhibition 42.6 ± 0.71% (n=3). According to the insecticidal activity assays performed, the essential oil R. chalepensis seems to be a promising source that could yield natural compounds that could be employed in stored product pest management.

Investigating alternatives to synthetic chemicals in pest management is essential. The bioactivity of Artemisia absinthium and A. dracunculus essential oils (EOs) was evaluated against two stored-product insect pests (Sitophilus granaries and Tribolium castaneum) and two root-knot nematodes (Meloidogyne incognita and M. chitwoodi). EOs were hydrodistilled and analyzed by GC-MS: A. absinthium consisted mainly of myrtenyl acetate (47.10%) and β-thujone (11.41%); A. dracunculus of methyleugenol (26.02%), β-asarone (14.04%), and elemicin (10.95%). In contact bioassays, A. absinthium caused 93.2–96.8% mortality against S. granarius, but minimal effect on T. castaneum. A. dracunculus caused 66.3–73.5% mortality against S. granarius, no effect on T. castaneum, yet reduced progeny by 87%. Both EOs strongly repelled T. castaneum but weakly affected S. granarius. A. dracunculus exhibited 100% nematicidal efficacy against M. incognita and 94.9% against M. chitwoodi; A. absinthium showed limited effect. A. dracunculus showed minimal hatching inhibition (<30%), whereas A. absinthium increased hatching. Sparse Partial Least Squares (sPLS) prioritized pulegone, methyleugenol, β-asarone, β-thujone, myrtenyl acetate, and β-phellandrene as constituents co-varying with AChE/BChE responses, with docking identifying pulegone as the top ligand. These findings demonstrate species-specific bioactivity patterns: A. dracunculus shows strong nematicidal and reproductive inhibitory effects, whereas A. absinthium shows potent acute toxicity and repellency against S. granarius, supporting multi-target biopesticide strategies to mitigate risks of synthetic chemical treatments.

The Journal of Academic Social Sciences