Toxicity and repellency of garlic (Allium sativumL.) extract grown in Iran againstTribolium castaneum(Herbst) larvae and adults

Abstract

Plant materials, such as essential oils and extracts, are useful tools for insect pest control. In this study, we report the repellent activity and fumigant toxicity of garlic extract Allium sativum L. (Amaryllidaceae) against larvae and adults of the red flour beetle, Tribolium castaneum (Herbst) (Col., Tenebrionidae). Experiments were carried out at 27 ± 1°C and 60 ± 5% RH in darkness. Results showed that mortality increases with increasing garlic extracts concentration and time. LC 50 values for larvae at 24 and 48 h were 267.37 and 145.8 μl/l air, and for adults, they were 127.90 and 90.8 μl/l air, respectively. The concentration of 225.8 μl/l air of the garlic extract yielded was 83.3% mortality of larvae after 48 h. The garlic extract had a strong repellent activity towards T. castaneum when tested in a filter paper arena test. After 4 h exposure to a low concentration (2.13 μl/cm 2 ) of garlic extracts, more than 95% repellence was achieved. Our results indicate lethal and repellent effects of garlic extracts on T. castaneum.

Repellent Effects of Selected Organic Leaf Extracts of Tithonia diversifolia (Hemsl.) A. Gray and Vernonia lasiopus (O. Hoffman) against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)

“…This observation was similar to the previous results for other plant extracts against different insect pests including S. zeamais , T. casteneum , and S. oryzae [ 57 , 58 ]. Similarly, the organic extracts of Eucalyptus globulus, Citrullus colocynthis , and O. basilicum have also shown strong repellency against S. oryzae, C. maculatus , and T. casteneum at remarkably lower concentrations [ 59 , 60 ].…”

“…Other studies have also indicated such trends where repellent activities of plant extracts on insects were independent of exposure time [ 11 ]. On the contrary, Mobki et al [ 58 ] reported that repellent activity of garlic extract to S. zeamais increased with duration of exposure. However, where an increase in repellency activities was noted for the first 3 hours of the test period followed by decrease in repellency is interesting.…”

Fumigant toxicity of some essential oils against Red Flour Beetles, Tribolium castaneum (Herbst) and its safety to mammals

“…Our results on fumigant toxicity of Allium sativum and Capsicum annuum on Tribolium castaneum (Herbst) larval and adult stages indicated that these essential oils had good fumigation toxicity.. These findings relate with Mobki et al (2014) who reported that mortality of T. castaneum increased with increasing garlic extract with concentration and time. The concentration of 225.8 μl/l air of the garlic extract generated 83.3% larval mortality after 48 hours.…”

Bioefficacy of organic extracts of A. sativum against S. zeamais (Coleoptera; Dryophthoridae)

“…Other studies carried out by Mobki et al [15] documented greater fumigant toxicities of garlic extracts against red flour beetle. This difference may be due to reasons based on solvents of extractions, extract concentration used and susceptibility of the two beetles, T. casteneum and S. zeamais to garlic components.…”