Lethal and Sublethal Effects of Eucalyptus camaldulensis and Mentha piperita Essential Oils on the Khapra Beetle (Coleoptera: Dermestidae) in Terms of Feeding Inhibition, Oviposition, and Seed Damage.

Trogoderma granarium Everts, the Khapra beetle, is a major pest of stored products, especially grains. In this study, fumigant toxicity and sublethal effects of Eucalyptus camaldulensis Dehnh. (Myrtaceae) and Mentha piperita L. (Lamiaceae) essential oils (EOs) were investigated against different growth stages of T. granarium. To assess the sublethal effects, insects were exposed to an LC20 or LC50 concentration of each essential oil, and the ability of these oils to deter feeding, oviposition, and damage to wheat seeds and overall mass were surveyed. At LC50 concentrations, M. piperita EO showed higher fumigant toxicity than E. camaldulensis EO against eggs, 2nd instar larvae, 4th instar larvae, and adults of T. granarium. Furthermore, the adults were more sensitive to the tested EOs than immatures. In free-choice tests, both larvae and adults showed a preference for control-treated wheat seeds than for seeds treated with an LC20 or LC50 concentration of EOs from E. camaldulensis or M. piperita. In a no-choice test, adult females exposed to EOs showed lower fecundity and fertility in comparison to control females not exposed to EOs. Treatment of wheat seeds with E. camaldulensis or M. piperita EOs resulted in a dose-specific reduction in the number of damaged seeds and seed weight loss when compared to control. According to our results, both tested EOs, especially EOs extracted from M. piperita, showed good potential for use in integrated pest management strategies against T. granarium.

Efficacy of AloeVera Cream in the Treatment of Paederus Dermatitis in Mice.

BACKGROUND: Dermatitis caused by Paederus beetle involves many people around the world, especially Iran. The symptoms include redness, itching and severe irritation. This study evaluated the effectiveness of the Aloevera cream on the treatment of dermatitis caused by Paederus beetles. METHODS: Forty male 6-8 weeks BALB/C mice were randomly divided into four groups of 10 mice. After removing the mice's back hair, the backs of mice were marked by a circle with a diameter of 3 mm. The Paederus beetles were collected from Babol in Mazandaran Province, northern Iran and transferred to the animal lab of Aja University of Medical Sciences, Tehran, Iran. The end of abdominal segment Paederus was cut with scissors and hemolymph content was pushed by forceps on the circle. Only hemolymph of one Paederus applied to the back of each mouse. Groups 1, 2, 3 and 4 were treated with the base (vehicle), dexamethasone 0.1%, Aloevera 0.5% and Aloevera 2% creams respectively. After 2 days, dermatitis appeared. Then the mentioned creams were applied on the mice once a day. The wound area was measured every day. Dermatitis surface area under curve (AUC) of each mouse was calculated for 17 days after induction of dermatitis. Statistical analysis of ANOVA was used. RESULTS: Application of Aloevera 0.5% and 2% significantly reduced the healing duration and dermatitis area in comparison with the vehicle and dexamethasone cream (P< 0.05). But dexamethasone had no significant effect on the healing of dermatitis as compared to vehicle. CONCLUSION: Aloevera may clinically effective in the treatment of Paederus dermatitis.