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The essential oils of aerial parts of three medicinal plants Artemisia khorassanica Podl., Rosmarinus officinalis L. and Mentha longifolia L. were isolated by hydrodistillation and investigated for their toxicity and repellency against Tribolium confusum Jacquelin du Val. at 27 ± 1 ºC and 60 ± 5% RH in darkness. The mortality of the adults increased with concentration from 185 to 1111 μl/l air and with exposure time from 9 to 24 h. A concentration of 185 μl/l air and exposure time of 24 h was sufficient to obtain nearly 100% kill of the adults in all of the three essential oils tested. At the highest concentration (1111 μl/l air) R. officinalis oil caused 15% mortality for an exposure time of 6-h. whilst, the oil of A. khorassanica resulted in 1% mortality at the same exposure time. The oil of A. khorassanica at 1111 μl/l air caused 81% mortality for 12-h exposure time. No significant differences were observed between the lethal time (LT₅₀) values at essential oil concentrations of 741 and 1111 μl/l air. For 24-h exposure time, the LC₅₀ values of A. khorassanica, R. officinalis and M. longifolia essential oils were estimated to be 22.45, 22.14 and 39.96 μl/l air respectively. Based on LC₅₀ values, adults of T. confusum showed similar susceptibility to the A. khorassanica and R. officinalis oils, but M. longifolia oil proved to be less toxic. In contrast to their low fumigant properties, the essential oil of M. longifolia had significantly higher repellency to T. confusum adults than did the other two.  

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Insecticidal efficacy of three diatomaceous earth (DE) formulations, DEBBM, DEA and F2 was evaluated on three different wheat cultivars, Chamran, Verinak and Behrang, against Tribolium confusum Jacqueline du Val. DEs were applied at the rates of 100, 200 and 300 mg/kg. Bioassays were carried out on wheat at 27 ± 1 °Cand 55 ± 5% RH in continuous darkness. Mortality of adults was counted after 2, 7 and 14 days of exposure. Adults of T. confusum were the most susceptible to DEBBM in Behrang. So that DEBBM concentration of 100 mg/kg after 7 days of exposure caused 98% mortality which reached 100 after 14 days. Therefore, Behrang was the most tolerant cultivar to T. confusum infestations. Furthermore, DEBBM was more effective than the other two testedformulations.