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Th is study investigated the potential eff ect of cold plasma on reducing residues of pesticides diazinon and chlorpyrifos in apples and cucumbers and its eff ects on property of products. Two separate concentrations of each pesticide with 500 and 1,000 ppm were prepared and the samples were inoculated by dipping them into the solutions. All samples treated with pesticides were exposed to cold plasma in a monopole cold plasma apparatus (DBD) run at 10 and 13 kV voltages. Liquid-liquid extraction (LLE) was used to remove pesticide residues from the samples. Eventually, high-performance liquid chromatography (HPLC) was used to measure the amount of pesticides in the samples. Also, to investigate generated metabolites, extracts were injected into a GC/MS apparatus. In addition, the eff ects of cold plasma on humidity, tissue hardness, color and the sugar percentage of products were analyzed. Th e results revealed that treatment of samples with cold plasma considerably reduced pesticide residues without leaving any traces of harmful or toxic substances. Furthermore, it did not have any undesirable eff ects on the color and texture of the samples. Th e effi ciency of this method increased with higher voltage and longer exposure time. In general, the best results were obtained by the combination of 500 ppm concentration, 10 min exposure and 13 kV voltages. Th e residues of diazinon were reduced better than the residues of chlorpyrifos. Apples were detoxifi ed much better than cucumbers. Also, cold plasma treatment transformed diazinon and chlorpyrifos pesticides into their less toxic metabolites. Th e results showed that with increased voltage and longer exposure time, cold plasma caused few changes in moisture and glucose content, texture hardness and color of products. Th ere were no signifi cant diff erence between treated samples and control in all treatments.

Recent research in bacteria-insect symbiosis has shown that lactic acid bacteria (LAB) establish symbiotic relationships with several Apis species. The current study was carried out to isolate and identify Lactobacillus bacteria housed in the gastrointestinal tract of the Asian dwarf honey bee (Apis florea), which is distributed in different regions of Iran. The current study was performed using 100 Gram-stained isolates, which were tested for catalase activity. Bacterial universal primers were used to amplify 16S rDNA genes isolated from bacterial colonies. Sequencing was done for 16S rDNA genes isolated from 43 bacteria. The phylogenetic analyses demonstrated that Lactobacillus flora found in the gastrointestinal tract of A. florea encompassed eight different phenotypes classified as three different species: L. kunkeei , L. plantarum , and L. apis. According to the specific association between bacteria and A. florea , we classified the Apis populations into three zones. Furthermore, the association of L. plantarum with insects foraging in citrus orchards might be explained by differences in nectar and pollen components resulting in the growth of different species of bacteria. Apis florea / lactic acid bacteria / 16S rDNA / symbiosis / Iran

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The effects of four commonly used pesticides, diazinon (EC 60%), phosalone (EC 35%), fipronil (Granular formulation 0.2%), and pyriproxifen (EC 10%), on functional response of Habrobracon hebetor (Say) (Hymenoptera: Braconidae) were investigated using two lepidopteran hosts, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) and Heliothis viriplaca (Hufnagel) (Lepidoptera: Noctuidae). Laboratory bioassays determined diazinon and fipronil as highly toxic insecticides for all developmental stages of the parasitoid, while the acute toxicity of phosalone and pyriproxyfen was moderate to very low depending on the life-stage studied. Larval, pupal, and adult stages of the parasitoid were exposed to sublethal concentrations (LC30) of insecticides, and the newly mated females were used to study functional response of the parasitoid to different host densities. With a single exception, a type II functional response was found for control and all insecticide treatments on all life stages and both host species. All insecticides tended to decrease the asymptote of the functional response curve and the maximum parasitism rate, probably by negatively affecting the searching efficiency (a') of the parasitoid. These results indicate that the control efficiency of parasitoids may be negatively affected by sublethal doses of pesticides, even though the type of functional response remains unchanged. As a potential solution, appropriate timing of pesticide application is required to avoid the antagonistic interactions with natural enemies under integrated management programs.