The effects of Carum copticum essential oil (CC EO) and thymol were assayed against fourth instar of Ephestia kuehniella Zeller by determining insecticidal activities and enzymatic responses. Concentrations of 5.42 and 6.81 ml/ml were obtained as LC50 values for CC EO and thymol, respectively. The activities of esterases, aminotransferases, aldolase, and lactate dehydrogenase significantly decreased in the treated larvae by CC EO and thymol. Significant increases in glutathione S-transferases, g-glutamyl transferase, and phosphatases were observed after treatment. Results revealed that CC EO and thymol significantly influenced the enzymatic activities of E. kuehniella leading to disruption of survival and metabolic responses.
Greenhouse whitefly, Trialeurodes vaporariorum is a major pest of horticultural and ornamental plants and is usually controlled with insecticides or biological control agents. In the current study, we examined the effects of synthesized zinc oxide nanoparticles (ZnO NPs) and Beauveria bassiana TS11 on T. vaporariorum adults. ZnO NPs were synthesized by precipitation method. Field emission scanning electron microscope images indicated that ZnO NPs were noncompacted uniformly. X-ray diffraction results confirmed the hexagonal wurtzite structure of ZnO NPs. Fourier transform infrared analysis showed an intense absorption peak at a range of 434-555 cm-1 related to Zn-O bond. In bioassays, adults were exposed to different concentrations of ZnO NPs (3, 5, 10, 15, 20 mg l-1) and fungi (104, 105, 106, 107, 108 spores ml-1). LC50 values for ZnO NPs and fungi were 7.35 mg l-1and 3.28×105 spores ml-1, respectively. Mortality rates obtained with ZnO NPs and fungi at the highest concentration were 91.6 % and 88.8 %, respectively. The results indicate a positive effect of ZnO NPs and B. bassiana TS11on adults. The current study was conducted under laboratory conditions, therefore, more studies are needed in field.
Ephestia kuehniella Zeller is a key pest by severe deficiencies on quantity and quality of stored products. Due to concerns made by synthetic insecticides, use of natural products (like botanical insecticides) is of great importance as an alternative pest management. In the current study, the effect of diallyl disulfide was determined on digestive enzymes and those involved in intermediary metabolism of E. kuehniella. Concentration of 0.31% was obtained as LC50 of diallyl disulfide followed by bioassay experiments. Activities of α-amylase, proteases, alanine aminotransferase, alkaline phosphatase and lactate dehydrogenase significantly decreased in the treated larvae, while the adverse effects were observed in case of triacylglyceride-lipase, aspartate aminotransferase, γ-glutamyl transferase, aldolase and acid phosphatase. Results confirmed that diallyl disulfide interrupted larval digestion by lower activities of digestive enzymes indicating significant effect on intermediary metabolism.
Oral toxicity of thymol, α-pinene, diallyl disulfide and trans-anethole, as well as their binary combinations, was studied on the fourth larval instars of Tribolium castaneum Herbst. Serial dilutions of chemicals were prepared from the stock solution to obtain the concentrations between 2.5-200 μl/ml prior mixing with 500 mg of the diet. LC50 values were determined as 6.79, 12.85, 8.52 and 1.03 μl/ml, for thymol, α-pinene, trans-anethole and diallyl disulfide after 24 hours and 3.74, 8.39, 6.48 and 0.68 μl/ml after 48 hours of exposure, respectively. LC50 values confirmed that diallyl disulfide and α-pinene were the highest and lowest toxic chemicals. The results show that combined treatment of thymol synergized α-pinene activity at 24 and 48 hours post treatments. In addition, “diallyl disulfide and thymol”, “thymol and trans-anethole” had additive effects on T. castaneum larvae. Our results suggest that the combination of thymol and α-pinene compounds were significantly more effective than each compounds alone on T. castaneum larvae.
Purpose: Feed resources for larval development act on attractive ability of Ectomyelois ceratoniae Zeller (Lepidoptera: Pyralidae) females. Its sex pheromone components are synthesized but due low stability not acceptable to recommend for pest control. As alternative method, the reared virgin female moths are suggested for baiting in pheromone traps. To aim this purpose we conducted this research. Method: The female moths were reared on dietary treatments including fruits of pomegranates and figs and semi-artificial diet in the laboratory. The traps were used for nine days on sunset in the pomegranate and fig orchards. By next morning, the captured moths by the traps were collected and counted. Results: The results confirmed that different treatments attracted different number of moths significantly. In pomegranate and fig orchards, means of captured moths by the traps baited with the reared females on pomegranate and fig fruits were more than other treatments, respectively. In both orchards, the reared females on semi-artificial diet captured less compare to two treatments. The interactions between treatments and orchards were significant different. Conclusion: We reported the efficiency of feeding supply during the larval period for sex pheromone production and their ability to attract moths of E. ceratoniae in the orchards.
Heat shock proteins (hsps) protect proteins in eukaryotic cells from damage. Expression of hsps in insects subject to different environmental stimuli is poorly characterized. Here, levels of expression of the hsps genes (hsp40, hsp70, and hsp90) were recorded in Apis mellifera Linnaeus (Hymenoptera: Apidae) workers after exposure to sublethal concentrations of thymol, eucalyptol, α-pinene, trans-anethole, diallyl disulfi de and infestation with Varroa mites. Our results show a dose-dependent upregulation in the levels of all the hsps tested after the bees were treated with thymol, eucalyptol and α-pinene. Although these upregulated expressions were statistically signifi cant for hsp70 and hsp90 when the bees were treated with thymol and eucalyptol, they were not signifi cant when treated with α-pinene. In addition, signifi cant down-regulated expressions of the hsp genes were recorded in the diallyl disulfi de treatment. The transcriptions of all the hsps tested were signifi cantly down-regulated when pupae were infested with different numbers (0–5) of Varroa mites. Thus, it is likely that hsps can be used as biomarkers of survival when honey bees are under toxic and pathogenic stress, but this needs to be confi rmed.
In the current study, the effects of Teucrium polium L. (Lamiaceae) essential oil (Tp EO) and α-pinene as a major component of this essential oil, were tested against Ephestia kuehniella Z. (Lep.: Pyralidae) for larvicidal activity, digestive enzymes and non-enzymatic (amount of macromolecules) responses. Concentrations of 4.91 and 10.66 μl/ml were determined as LC50 values for Tp EO and α-pinene, respectively. The activities of α-amylase, triacylglycerol lipase, general protease, serine proteases (trypsin and chymotrypsin-like), carboxy- and aminopeptidases significantly decreased when the larvae fed on the diet supplemented with Tp EO and α-pinene but significant increases were observed in elastase-like proteinase. The amount of protein, glycogen and triglyceride decreased in the treated larvae by both treatments. The results showed that the digestive enzymes and non enzymatic activities of the treated larvae were decreased compared to the control. Therefore, Tp EO and α-pinene are suggested as botanicals for controlling flour moth larvae.
Chitosan and its derivatives have received attention as alternatives to pesticides in agriculture. Insects are a good source for chitosan isolation. In the present study, chitosan was obtained from Chrotogonus trachypterus (Orthoptera, Acrididae), and its N-alkyl derivatives were synthesized. Experiments were conducted to assay their aphicidal activity against three aphid species. All derivatives had a higher aphicidal action (> 98%) than pure chitosan (> 15.2%) against aphid species. N-(3-phenyl butyl) chitosan and N-(ethyl butyl) chitosan were the most and least active derivatives. Results confirmed that the chemical modification of chitosan increased the aphicidal activity. A comparison of the aphicidal activities confirmed that N-alkyl derivatives of commercial chitosan had more toxic effects on aphid species than derivatives of grasshopper chitosan. No significant differences were observed between the two groups of commercial and C. trachypterus chitosan derivatives. This encourages us to introduce N-alkyl derivatives of grasshopper chitosan as a promising alternative source of aphicides in future.
Purpose: Bactrocera zonata (Diptera, Tephritidae), is considered as a dangerous pest of mango in the south of Iran, which its control is one of the main concerns of farmers who are facing numerous problems. To assay the different methods for controlling B. zonata, this study was carried out. Method: The treatments were, A) spraying 7% methyl eugenol+7% technical malathion on trunk and tree branches, B) soaking 8-10 layers of jute sacks with previous treatment that were attached to tree branches, C) bucket trap along with chipboard that was saturated with 6 ml of methyl eugenol, D) spraying 3% protein hydrolysate+3 ppm malathion (EC 57%) on the trunk and tree branches, E) spraying 3% sugar permit+3 ppm malathion on the trunk and tree branches, and F) control (no treatment). The experiments were repeated at two consecutive years. Results: The results confirmed that the differences among treatments and the effect of the year on the treatments were significant (p>1%). The treatment D captured the highest numbers of fruit flies in both years of replications. The treatments had significant effect on percentage of fruit infestation. Conclusion: The findings confirmed that treatments C and B had the greatest impact on pest control.
The current study aimed to determine the potential effects of three essential oil constituents, α-pinene, transanethole, and thymol, on antioxidant system and acetylcholine esterase (AChE) of Ephestia kuehniella Zeller. The 4th instar larvae were initially fed on an artificial diet containing an LC50 concentration of each above-mentioned compounds separately prior to being undertaken for sample preparation and biochemical assays. The significant higher activities of superoxide dismutase, peroxidase and catalase were observed in the treated-larvae at both time intervals. Similar findings were found in the activity of glutathione S-transferase by using both reagents. Although activities of ascorbate peroxidase and glycerol-6-phosphate dehydrogenase increased in the treated larvae by all constituents while glycerol-6-phosphate dehydrogenase showed no statistically different activity among the larvae fed on α-pinene, trans-anethole, and thymol. The concentration of malondialdehyde and the ratio of oxidized (RSSR) to reduced (RSH) thiols showed statistical differences among control and treated larvae except for time interval of 24 h regarding the ratio of RSSR/RSH. Finally, our results demonstrated a significant decrease of AChE activity in the treated larvae by all constituents after 24 h while no statistical differences were found between control and trans-anethole after 24 h. Also, in vitro analysis revealed significant inhibition of AChE representing IC50 values of 0.864, 0.490 and 0.137 μl/ml for α-pinene, trans-anethole, and thymol, respectively. These results determined significant effects of administered constituents on induction of antioxidant system and inhibition of a nervous system component which expand our knowledge on physiological turbulences due to essential oil treatment.
شته جالیز Aphis gossypii Glover (Hem.: Aphididae) از گونه¬های چندخوار و خسارت¬زا در مزارع و گلخانه¬ها می¬باشد. هم¬اکنون مبارزه با شته¬ها به استفاده از حشره¬کش¬های شیمیایی وابسته است. به دلیل استفاده¬ی مداوم سموم، گونه¬های فراوانی از شته¬ها به تعداد زیادی از ترکیبات شیمیایی مقاوم شده¬اند. بنابراین در مدیریت تلفیقی شته¬ها جستجوی روش جایگزین جهت مبارزه با این آفات ضروری می باشد. در این مطالعه، بررسی کیفی ترکیبات شیمیایی عصاره¬ی اتانولی علف شور (Salsola imbricata) انجام و اثر حشره¬کشی آن روی شته جالیز در شرایط آزمایشگاهی در قالب طرح کاملاً تصادفی بررسی شد. نتایج حاصل از آزمایش¬ها نشان داد، عصاره¬ی علف شور جنوبی در غلظت¬های بین 33/63 تا 2016/99 میکروگرم بر سانتیمتر مربع باعث 20 تا 73 درصد تلفات شته¬ی بالغ شد و مقدار غلضت کشنده 50 درصد (LC50) پس از 24 ساعت از کاربرد عصاره¬ی روی شته، 340/06 میکروگرم بر سانتی¬متر مربع محاسبه گردید. بررسی کیفی ترکیبات عصاره اتانولی علف شور نشان داد که این گیاه، دارای ترکیبات با خواص حشره کشی از جمله فلاونوئید، استروئید، تانن، تری ترپنوئید و گلیکوزید بوده، اما فاقد ساپونین می¬باشد.
This paper reports on a new species of mites of the genus Laelaspis from Iran – Laelaspis latisetus sp. nov. was collected clinging to Pheidole pallidula (Nylander) (Hymenoptera, Formicidae) from southeast of Iran. The new species is described and illustrations provided based on morphological characters of the adult female. An updated key to all known Iranian species of the genus is presented.
Toxicity Allium sativum and Eucalyptus globulus essential oils were investigated against Ephestia kuehniella larvae in addition to physiological effects on digestive enzymes, intermediary metabolism, antioxidant response and storage macromolecules. The LC50s of 2.801 and 6.111 ml/ml were recorded for A. sativum- and E. globulus EOs as the highest concentrations caused 83.3% and 80% of larval mortality. The lowest activities of a-amylase, TAG-lipase, and carboxypeptidase were recorded in the larvae treated by A. sativum EO, while the larvae treated by E. globulus EO showed the lowest activities of trypsin, chymotrypsin, and aminopeptidase. The activities of elastase and glucosidases decreased in the treated larvae but no significant differences were recorded between EOs. Activities of esterase and glutathione S-transferase significantly increased in the larvae treated by EOs similar to aminotransferases while the activities of lactate dehydrogenase, acid- and alkaline phosphatases significantly decreased in the EO-treated larvae. The higher activities of ascorbate peroxidase, glycerol-6-phosphate dehydrogenase, malondialdehyde, and ratio of RSSR/RSH were found in the EO-treated larvae while superoxide dismutase, peroxidase, and catalase had the highest activities in EgEO-treated larvae. Both EOs significantly decreased the activity of acetylcholine esterase and the amounts of storage macromolecules, protein, glycogen, and triglyceride.
سیستم بویایی حشرات آنها را قادر می سازد تا بتوانند مقادیر بسیار اندک از وجود آلاینده های محیطی مختلف مانند فلزات سنگین، سموم شیمیایی و متابولیتهای ثانویه عوامل بیماریزای مختلف مانند باکتریها را شناسایی نمایند. این فرایند «پایش زیستی » نامیده می شود که بدلیل کم هزینه بودن در مقایسه با سایر روشهای پایش، توجه محققین را به خود جلب کرده است. به اثبات رسیده که می توان موجودات مختلف مانند زنبورعسل را بدلیل حساسیت بالای حس بویایی از طریق شرطی سازی موثر مبتنی بر پاسخ رفتاری قابل مشاهده به بوها برای تشخیص داروهای قاچاق، مواد منفجره و حتی بیماری های انسانی آموزش داده و در مکان های خاص جهت شناسایی استفاده نمود. بطور کلی پایش آلاینده های زیست محیطی از طریق ارزیابی رفتارهای خاص زنبورعسل مانند واکنش گسترش خرطوم در پاسخ به تحریک با آلاینده ها و همچنین سنجش بقایای آنها در فراورده های کندو و یا در بدن زنبورهای عسل امکان پذیر است. در این مقاله به بررسی توانایی زنبورعسل جهت پایش آلاینده ها و سایر ترکیبات شیمیایی در محیط زیست از طریق شرطی سازی و یا سنجش بقایای مواد شیمیایی مختلف در کندوها پرداخته می شود.