In this study, the opportunity to enhance the insecticidal activity of Rosmarinus officinalis essential oil was studied for effective management of the red flour beetle, Tribolium castaneum, as a stored product pest beetle. Nanoprecipitation method was used to prepare rosemary oil-loaded nanocapsules. Bioassays were conducted at 27-30°C temperature and 70-75 % relative humidity in the dark. Fumigant toxicity of the non-formulated oil and nanocapsules of R. officinalis were investigated at 13.20, 15.92, 19.12, 23.04, and 27.76 μL/L air after 24 and 72 h exposure and the contact toxicity of the non-formulated oil and nanocapsules were investigated at 4.28, 3.55, 2.95, 2.45 and 2.36 μL/cm 2 after 24 h exposure. The major constituents of the essential oil of rosemary were α-Pinene, 1,8-cineol, camphor, and cis-verbenone. Nanocapsules presented an average size (145 AE 15 nm) (AE standard error [SE]) with a polydispersity index below 0.3, a negative zeta potential (À11.0 AE 0.5 mV), and a high encapsulation efficiency (78.20 AE 0.93 %). Scanning electron microscope photomicrograph of rosemary oil-loaded nanocapsules showed the presence of spherical nanocapsules with regular and homogeneous surfaces. In fumigant and contact toxicity, there were significant differences between non-formulated and rosemary oil-loaded nanocapsules in all the concentrations and times. The results suggested that nanoencapsulated essential oils from R. officinalis can be used for effective control in T. castaneum. When this technique is used, it can produce pesticides that have controlled-release properties and reduce the concentration of the applied doses and number of applications.

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Pistachio fruit hull borer, Arimania komaroffi Ragonot (Lep.: Pyralidae), is one the most important pests of pistachio in Iran. The larvae spin web as well as bore into young fruits, and the infested fruits fall off the trees. The second-generation adult moths appear in August and September, and their offspring feed on the fruit hull. Results indicated the presence of α-amylase, α-glucosidase, β-glucosidase, α-galactosidase, β-galactosidase and some proteases in the digestive tract of the pest. Highest activities of α-amylase, α-glucosidase, β-glucosidase, α-galactosidase and β-galactosidase were at pH 10, 7, 7, 6 and pH 6, respectively. Highest activities of trypsin, chymotrypsin and elastase of larval midgut were at pH 11. Zymogram analysis of α-amylase, α-glucosidase, β-glucosidase, tryptic, chymotryptic and elastase using native-PAGE revealed 1, 1, 2, 3, 3 and 2 bands of activity respectively, in A. komaroffi. One band was disappeared in the presence of the inhibitor TLCK, but no further inhibition by the inhibitors TPCK was observed. The results can be of help for designing new strategies for controlling the pistachio fruit hull borer based on natural proteases and carbohydrase inhibitors.

Humidity is probably the most important abiotic factor influencing life cycles, distribution, survival, and population dynamics of stored product pests. Although most of these pests can complete their life cycles in any given relative humidity, their prolonged development time, as well as decreased emergence rate and fecundity, have been well documented in several previous studies. In the present study, we evaluated the changes in energetic substances (lipids, soluble carbohydrates, glycogen, and proteins) accumulated in different life stages of larvae and adults of Tribolium castaneum in response to different relative humidity levels (5, 12, 22, 30, 45, and 65%). The results showed that young larvae were more susceptible to low relative humidity levels and desiccation stress. Larvae tended to accumulate higher proportions of lipids during earlier stages while their energy content shifted towards proteins with an increase in their age. Adult beetles experienced a significant decrease in their protein content immediately after they initiated reproduction. The importance of these fluctuations in the biology of the red flour beetles was discussed in detail.

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