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Extensive usage of synthetic chemical pesticides has collateral effects in harming human and animal health and the environment and promoting the development of resistance in pests. The potential of plant compounds as bio insecticides has been described as a promising field of agricultural development. The present study involved the use of Artemisia annua essential oils to evaluate their cytotoxic activities against an established cell line of lesser mulberry pyralid. Five types of hemocytes were recognized (prohaemocytes, plasmatocytes, granulocytes, oenocytoids, and spherulocytes) in the primary cultures maintained in Ex-Cell media with 10% fetal bovine serum (FBS). Artemisia annua essential oils produced noticeable cytotoxicity against the insect cell lines. Applied at a concentration 500 ppm, oils extracted from the vegetative or flowering stages of A. annua produced 71% and 80% cell death, respectively. Nanoemulsions of EOs from the vegetative or flowering stages of A. annua killed 67 and 60% of the cells, respectively. This study has clearly shown significant bioactivities of A. annua secondary metabolites to insect cell lines.

The box tree moth, Cydalima perspectalis (Walker), is an invasive pest of Hyrcanian forests in Iran. In the current study, the effects of two boxwood species, Buxus hyrcana Pojark and B. microphylla Sieb. and Zucc. (Buxales: Buxaceae), were examined on ecophysiology of the pest. The demographic parameters were evaluated based on the age-stage, two-sex life table theory. The physiological characteristics of C. perspectalis were considered through fresh/dry weights and individually/group rearing methods. The results showed that C. perspectalis larvae were able to develop, survive and reproduce on both boxwood species. The developmental times were 41.62 and 41.46 days on B. hyrcana and B. microphylla, respectively. The total lifespan did not differ on boxwood species. However, the difference of fecundity on B. hyrcana (412.82 eggs/female) and B. microphylla (286.06 eggs/female) was significant. The intrinsic rate of increase (r) and finite rate of increase (λ) were significantly higher on B. hyrcana than B. microphylla. The nutritional indices showed that the consumption index (CI) on B. hyrcana were significantly lower than on B. microphylla based on fresh/dry weights in both rearing methods. Conversely, the efficiency of conversion of digested food (ECD) and the efficiency of conversion of ingested food (ECI) on B. hyrcana were significantly higher than on B. microphylla. Despite nonsignificant differences in leaf nutrient contents (except calcium), total protein, triglyceride, and alkaline phosphatase activity were inversely different in larvae compared to adult stage on boxwood species. These findings could help to comprehensively understand the performance of the pest on boxwood species.

Orosanga japonica Melichar (Hemiptera: Ricaniidae) is an invasive polyphagous pest in Iran. The planthopper damaged host plants by sap-sucking and egg laying on new twigs. This study aimed to determine the life table parameters of O. japonica on Rubus ulmifolius Schoot (elm leaf blackberry) and Melia azedarach L. (chinaberry) under field conditions in Rudsar (North of Iran) during 2019–2020. The collected life history data were analyzed based on age-stage, two-sex life table theory. The results showed that the incubation period of O. japonica was too long (≈ 270 days) on both host plants. The nymphs emerged from mid-May 2020. The planthopper had five nymphal stages under field conditions. The nymphal duration was 41.39 ± 0.56 days and 38.13 ± 0.62 days on R. ulmifolius and M. azedarach, respectively. The total preadult survival rates were 53.2% and 51.7% on R. ulmifolius and M. azedarach, respectively. Based on the results, a significant shorter total developmental time was observed on M. azedarach. When adults emerged in late July, they laid eggs after 26.05 days and 26.75 days on R. ulmifolius and M. azedarach, respectively. The fecundity on M. azedarach (131.69 egg/female) was significantly higher than that on R. ulmifolius. However, the life table parameters were all not significantly different on the two host plants. The intrinsic rate of increase (r) were 0.0097 ± 0.0005 day−1 and 0.0105 ± 0.0006 day−1 on R. ulmifolius and M. azedarach, respectively. Generally, these findings could be helpful to establish an efficient management strategy for this exotic pest.

Thymus vulgaris is a plant with known insecticidal properties. In order to explore its use in the control of the mulberry snout moth, the essential oil this plant and two of its major components, thymol and carvacrol, were evaluated in laboratory bioassays. GC-MS analysis of the oil depicted thymol (26.9%) and carvacrol (5.7%) as the major constituents. The estimated LD50 values for thyme essential oil, thymol and carvacrol were 2.82, 32.18 and 56.54 µg/larva, respectively. However, the thyme essential oil was more toxic than its two main compounds.The activity of certain detoxifying enzymes such as α- and β-esterase, glutathione S-transferase and cytochrome P450 were significantly inhibited in thymol-treated larvae compared to the control group. Similarly, the activity of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and alkaline phosphatases enzymes in thymol-treated larvae decreased while the activity of acid phosphatases increased. Our results suggest that thyme essential oil and its components have potential for the control of G. pyloalis larvae in mulberry orchards, where no synthetic chemicals are allowed.

Although the use of synthetic chemicals is the principal method for insect pest management, their widespread application has led to numerous side effects, including environmental pollution and threats to human and animal health. Plant essential oils have been introduced as promising natural substitutes for synthetic insecticides. However, high volatility and/or low durability are the main limiting factors for essential oil application for control of insect pests. Accordingly, along with an evaluation of the fumigant toxicity of

The humoral and cellular defenses are crtitical in insects’ immunity. In the present study we focused on individual haemocyt types of mulberry pyralid, Glyphodes pyloalis Walker (Lep.; Pyralidae) and examined them for the first time by light, differential interference contrast, scanning and transmission electron microscopy. Like many lepidopterous insects five types of haemocytes were identified; prohaemocytes, plasmatocytes, granulocytes, oenocytoids and spherulocytes. The small, rounded to ovoid cells with homogenous cytoplasm and large nuclei compared to cytoplasm were designated as prohaemocyts. The plasmatocytes were polymorphic and variable in sizes. The oval to spherical cells, with plenty of rough endoplasmic reticula, mitochondria, and microtubules in the cytoplasm were designated as the granulocytes. The oenocytoids were round or spherical with elongated eccentric nucleus and cytoplasm with small mitochondria and few rough endoplasmic reticula. Total haemocyte counts in different larval instars showed that THC increases as the larval age increase. Differential counts of haemocytes revealed the plasmatocytes and granulocytes as the most abundant haemocyte types in comparison with other types.

Adalia decempunctata (L.) is a common predator in agro ecosystems. Here, the effects of low-temperature storage on biological parameters, energy reserves, and antioxidant enzymes were investigated. Eggs, larvae, and pupae of this predator were maintained for 1-4 weeks and adults for different days (20, 35, 50, and 65 d) at 4, 7, and 10 °C in darkness and 70 ± 5% R.H. After storage of 20 days, the survival rate in male and female insects was90% in 4, 7, and 10 ± 1 °C. In 65 days, the highest survival rate for adult insects was recorded at 4 °C. Effect of cold storage on the performance of adult's A. decempunctata was not statistically different for periods up to 35 days, but decreased longer duration (65 days). The female adults were able to tolerate the cold storage period by producing higher amounts of glucose and antioxidant enzymes, thus displaying a high survival rate. Based on our results, maintaining A. decempunctata adults at low temperatures (i.e. 4, 7, and 10 °C) for 20 or 35 days performed best without loss of quality.

Plant essential oils may serve as safe alternatives to detrimental synthetic pesticides due to relatively lower side effects on the environment and non-targeted organisms. The current study was conducted to investigate the ovicidal toxicity and physiological disruptions of six medicinal plant essential oils, including Artemisia annua L., Lavandula angustifolia Mill., Origanum vulgare L., Rosmarinus officinalis Spenn., Satureja hortensis L., and Thymus vulgaris L., on elm leaf beetle Xanthogaleruca luteola (Mull.). The LC50 (Lethal Concentration to kill 50% of tested insects) values of 122.8, 287.5, 152.8, 180.6, 315.9, and 1366.2 ppm were recorded for T. vulgaris, L. angustifolia, A. annua, S. hortensis, R. officinalis, and O. vulgare, respectively, 72 h after treatment of 3-day-old eggs of the pest. Significant decreases in the amounts of glucose, protein, and triglyceride macromolecules were also observed after treatment. The application of essential oils derived from T. vulgaris, A. annua, and S. hortensis at 400 ppm revealed 100% ovicidal activity. Accordingly, tested essential oils, particularly the essential oil of T. vulgaris, have been promising potential as biorational insecticides in the management of X. luteola.

Extensive usage of synthetic pesticides has proved to be destructive to all living being and the resurgence of pest resistance. Compounds derived from certain plants are usually safer compared to chemical control of pest. The present study thus intended to use Thymus vulgaris essential oil (EO) and two of its derivatives including thymol and carvacrol in order to see their deleterious effects on Glyphodes pyloalis (Walker). We also studied the oil components. This pest has recently become a serious concern for the silk industry. Our results showed that the thyme EO contain several components including thymol (26.9%), ρ-Cymene (14.54%), linalool (13.39%) and carvacrol (5.7%). Our toxicity tests revealed an estimated LD

Development and demography of Adalia decempunctata L. were studied under laboratory conditions at seven constant temperatures (12, 16, 20, 24, 28, 32 and 36°C). First instar larvae failed to develop to second instar at 12°С and no development occurred at 36°C. The total developmental time varied from 47.92 days at 16°C to 15.94 days at 28°C and increased at 32°C. The lower temperature thresholds of 11.05 and 9.90°C, and thermal constants of 290.84 day-degree and 326.34 day-degree were estimated by traditional and Ikemoto- Takai linear models, respectively. The lower temperature threshold (Tmin) values estimated by Analytis, Briere-1, Briere-2 and Lactin-2 for total immature stages were 11.99, 12.24, 10.30 and 10.8°C, respectively. The estimated fastest developmental temperatures (Tfast) by the Analytis, Briere-1, Briere-2 and Lactin-2 for overall immature stages development of A. decempunctata were 31.5, 31.1, 30.7 and 31.7°C, respectively. Analytis, Briere-1, Briere-2 and Lactin-2 measured the upper temperature threshold (Tmax) at 33.14, 36.65, 32.75 and 32.61°C. The age-stage specific survival rate (sxj) curves clearly depicted the highest and lowest survival rates at 16 and 32°C for males and females. The age-specific fecundity (mx) curves revealed higher fecundity rate when fed A. gossypii at 24 and 28°C. The highest and lowest values of intrinsic rate of increase (r) were observed at 28 and 16°C (0.1945 d–1 and 0.0592 d–1, respectively). Also, the trend of changes in the finite rate of increase (λ) was analogous with intrinsic rate of increase. The longest and shortest mean generation time (T) was observed at 16 and 28°C, respectively and the highest net reproductive rates (R0) was estimated at 24 and 28°C. According to the results, the most suitable temperature seems to be 28°C due to the shortest developmental time, highest survival rate, and highest intrinsic rate of increase.

Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), is one of the most important pests of various agricultural crops with global distribution. Influence of four concentrations of gibberellic acid (GA3) (100, 200, 400, 800 mg/kg diet) on life table parameters of H. armigera was studied at 26 ± 1 °C, 65 ± 5% RH and a photoperiod of 16 L: 8 D h. Data were analyzed based on the age-stage, two-sex life table theory. The results demonstrated significant differences among various treatments on the development time of different stages and fecundity of H. armigera. The highest mean development time of fifth and sixth instars was observed at 800 mg GA3/kg diet but was not significantly different with either control, 100 or 200 mg GA3/kg diet. According to the results obtained, life table parameters were affected by GA3. The lowest finite and intrinsic rates of increase of H. armigera were observed with 800 mg GA3/kg diet. The net reproductive rate of H. armigera on five treated diets varied from 486.21 ± 98.22 to 1269.02 ± 218.97 offspring, being lowest at 800 mg GA3/kg diet treated diet and highest in control. Different concentrations of GA3 significantly influenced mean generation time, the longest at 800 mg GA3/kg diet (49.71 ± 0.31 days) and the shortest in control (43.80 ± 0.25 days). The data obtained in this study indicate that GA3 treatment has notable effects on the development, reproduction, and survival of H. armigera particularly at higher concentrations tested.

The overuse of synthetic pesticides in plant protection strategies has resulted in numerous side effects, including environmental contamination, food staff residues, and a threat to non-target organisms. Several studies have been performed to assess the pesticidal effects of plant-derived essential oils and their components, as partially safe and effective agents, on economically important pests. The essential oils isolated from Satureja species are being used in medicinal, cosmetic, and food industries. Their great potential in pest management is promising, which is related to high amounts of terpenes presented in this genus. This review is focused on the acute and chronic acaricidal, insecticidal, and nematicidal effects of Satureja essential oil and their main components. The effects of eighteen Satureja species are documented, considering lethality, repellency, developmental inhibitory, and adverse effects on the feeding, life cycle, oviposition, and egg hatching. Further, the biochemical impairment, including impairments in esterases, acetylcholinesterase, and cytochrome P450 monooxygenases functions, are also considered. Finally, encapsulation and emulsification methods, based on controlled-release techniques, are suggested to overcome the low persistence and water solubility restrictions of these biopesticides. The present review offers Satureja essential oils and their major components as valuable alternatives to synthetic pesticides in the future of pest management.

The fall webworm, Hyphantria cunea (Drury), is a harmful polyphagous global defoliator. The major chemical components of Artemisia annua essential oil (EO) was found to contain (±)-camphor (16.42%), 1,8-cineole (6.22%), α-pinene (6%), caryophyllene (5.19%), and α-selinene (5.17%). The highest toxicity was recorded for EO of A. annua (LD

Although the use of synthetic chemicals is the principal method for insect pest management, their widespread application has led to numerous side effects, including environmental pollution and threats to human and animal health. Plant essential oils have been introduced as promising natural substitutes for synthetic insecticides. However, high volatility and/or low durability are the main limiting factors for essential oil application for control of insect pests. Accordingly, along with an evaluation of the fumigant toxicity of Eucalyptus largiflorens essential oil against the cowpea weevil, Callosobruchus maculatus, essential oil was nanoencapsulated by two mesoporous silicates, MCM-41 and zeolite 3A, to enhance fumigant persistence and toxicity. The chemical profile of essential oil was also analyzed through gas chromatographic-mass spectrometry. E. largiflorens essential oil showed significant concentration-dependent toxicity against insect pests; a concentration of 5.16 μL/L resulted in 100% mortality after 48 h. The toxicity of essential oil could be attributed to the presence of various insecticidal terpenes, such as spathulenol (15.6%), cryptone (7.0%), and 1,8-cineole (5.8%). Fumigant persistence was increased from 6 days to 19 and 17 days for pure and capsulated essential oil with MCM-41 and Zeolite 3A, respectively. The insect mortality also increased from 99 insects in pure essential oil to 178 and 180 insects in MCM-41 and Zeolite 3A encapsulated formulations, respectively. Therefore, the encapsulation of E. largiflorens essential oil by MCM- 41 and Zeolite 3A is a beneficial method for enhancing its persistence and toxicity against C. maculatus.

Helicoverpa armigera Nucleopolyhedrovirus (HearNPV) (genus: Alphabaculovirus, incertae sedis: Baculoviridae) has been used to control Helicoverpa armigera (Hübner). A reproducible and susceptible cell line was prepared from the hemocytes of Ephestia kuehniella in Grace and Ex-Cell 420 media. The population doubling time of these cloned cell cultures during the logarithmic phase were about 2.3 and 3.7 d for Ex-Cell 420 and Grace’s media, respectively. When 60% confluence occurred, cells were infected by viral inoculums. All biochemical compounds were significantly changed relevant to cellular metabolism due to HearNPV infection. In order to improve its stability, two polymer formulations were used, i.e., formulation A (sodium alginate, gelatin, starch, and molasses) and formulation B (cottonseed kernel extract, Bran, glycerol, boric acid, egg white, and sugar). Formulant A provided high photostability by exhibiting 83.2 ± 3% efficacy and 88.66 ± 2.1% original activities remaining after 72 h UV exposure. Percentage original activity remaining of unformulated HearNPV and formulated mixture of B was 38.66 ± 2.6% and 9.33 ± 1.3%, respectively, after 72 h UV-irradiation. The virulence of the HearNPV proliferated from the Ex-Cell medium was similar to the virulence of wild-type HearNPV with LC50 of 7.7×105 OBs/ml. Formulant A, revealed only 20.0 ± 1% reduction in efficacy while the unformulated virus and formulant B faced a reduction of 90.0 ± 3% and 64.0 ± 2% after 72 h of UVA irradiation. Formulant A thus showed a high potential to protect HearNPVs microparticles against UV-inactivation suggesting a new platform for more efficient biological-management of cotton bollworm (specific name Helicoverpa armigera, genus: Helicoverpa, Lepidoptera: Noctuidae) in vivo.

The effects of Ajwain essential oil and its major constituents were investigated against newly fourth instar larvae of Tuta absoluta, a major pest of tomato cropping in Iran and other parts of the world. The study included individual efficacy of each compound and determination of their synergistic or antagonistic efficacy. We also determined the activities of detoxifying enzymes in treated insects. According to the results, the Ajwain essential oil and thymol showed the highest toxicity against T. absoluta larvae (LC50 = 6.14 and 7.72 μL/mL, respectively, and LC30 = 3.05 and 3.57 μL/mL, respectively). The ɤ-terpinene and p-cymene had lesser toxicity compared to other compounds. The larvicidal potency increased by binary mixtures of active constituents, such as thymol + p-cymene and thymol + ɤ-terpinene. On the other hand, ɤ-terpinene + p-cymene mixture demonstrated antagonistic effect on the larvae. The esterases and glutathione S-transferases were significantly increased in all treatments. Finally, our results revealed a significant inhibition of AChE activity in the treated larvae by all treatments except for ɤ-terpinene + p-cymene. In vitro experiments representing AChE inhibition with IC50 values were recorded 0.370, 0.457, 0.528, 1.094 and 1.323 μL/mL for thymol + p-cymene, thymol + ɤ-terpinene, thymol, ɤ-terpinene and p-cymene, respectively. Thymol demonstrated significant potential as a controlling agent of T. absoluta larvae, both larvicidal, compatible with other compounds with strong AChE inhibition properties. These finding could pave the way for development of new botanicals based on EO constituents which should be completed with preparation of an efficient formulation and field trials.

Botanical extracts are an important source of bio-pesticides and are generally considered safe to the environment. Artemisia annua L, a medicinal plant, well known for its antimalarial potential, was evaluated as a source of a type of essential oil collected during vegetative growth stage against Glyphodes pyloalis Walker. The main chemical components of the essential oil at vegetative stage of Artemisia annua was analyzed by GC- MS and contained 1,8-cineole (18.68%), Camphor (11.4%), α-Pinene (9.3%) and 3-Carene (6.3%). The LC50 of this plant oil was estimated to be 0.652% W/V and 2.585 μL/L air incorporated orally and fumigation, respectively. The digestive enzymes such as α-amylases, Proteases, Lipases and α- and β-glucosidases were considereably inhibited in treated larvae compared with controls. Similarly, the amount of protein, glucose, and triglyceride were decreased in the treated larvae by methods used. The lower hemocyte numbers, nodule formation and activity of phenoloxidases after injection of Beauveria bassiana and latex beads showed its EO effect on immunity. The anatomy of the larval midgut after treatment showed degeneration in digestive cells. Emerging adult's ovaries showed significant changes in the ovarian sheath and lack of yolk spheres. The present investigation in accordance with our previous studies may ultimately lead to a formulation in controlling this notorious pest especially in mulberry orchards where the use of conventional chemicals is restricted.

The Glyphodes pyloalis Walker, is considered as the most destructive insect pest of mulberry. The current study incorporated Artemisia annua essential oils loaded mesoporous materials including pure silica MCM-41 and clinoptilolite zeolite. The procedure prolonged the stability and fumigant toxicity compared to crude essential oil by 23 days. A nanoemulsion of A. annua essential oil with tween 80 and water via ultrasonication showed moderate larvicidal activity. The estimated LC50 values of 0.380% and 0.511% W/V in oral toxicity and 3.043 and 4.034 μL/L air in fumigant toxicity were recorded. The fumigant toxicity constancy of this formulation from essential oil was observed for up to 20 days. The current results are indicative of valuable potential of A. annua essentials oil in controlling the lesser mulberry pyralid based on environmentally friendly points.

Elm leaf beetle, Xanthogaleruca luteola Müller (Col.: Chrysomelidae) a pest of ornamental elms. Thyme, Thymus vulgaris (Lamiaceae) is an important medicinal. In this study, effect of Thymus vulgaris L. essential oil was tested on X. luteola in laboratory. The LC 30 and LC 50 values were estimated by leaf dipping method to third instar larvae (LC30 =2.065 and LC50 =4.237% W/V). The feeding efficiency was significantly reduced in treated larvae except the approximate digestibility (94.82 in control and 98.23 in treatment). The treated larvae showed a significant reduction key biochemicals. Reduced glucose and uric acid but increased protein level was seen. Severe reduction in ovarian texture both morphologically and histologically was observed which depicts a prolonged effect of the used EO on survivors. We believe that the thyme EO has the potential to be formulated for smaller scale trial to meet the needs of an environmental friendly compound.

Plant lectins could reduce insect populations by imposing imbalances in biology and physiology. Here, an agglutinin was extracted from Polygonum persicaria L. (PPA; Polygonales: Polygonaceae) and its effects were investigated on life table parameters and antioxidant system of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae). PPA significantly changed demographic parameters showing adverse effects on age-stage survival rate (Sxj), age-specific survival rate (lx), age-specific fecundity rate (mx), age stage specific fecundity (fxj), and life expectancy (exj). Also, life table parameters including net reproduction rate (R0) (Offspring/female), intrinsic rate of population increase (rm) (days-1), finite rate of increase (λ) (days-1), gross reproduction rate (GRR) (Offspring/female) significantly decreased in the PPA-treated H. armigera compared to control except for mean generation time (T) (days). Activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CA), peroxidase (POX), glutathione S-transferase (GST) and glucose 6-phosphate dehydrogenase (GPDH) increased statistically in the PPA-treated larvae compared to control while no significant difference was observed in the activity of ascorbate peroxidase (APOX) activity. Moreover, ratio of RSSR/RSH and concentration of malondialdehyde (MDA) were found to be statistically higher in PPA-treated larvae than control. The current results clearly showed that PPA not only had a negative impact on demography of H. armigera but also induced antioxidant raise by releasing free radicals. These released radicals, together with impaired digestion and absorption observed in our previous report, could be considered as a reason for reducing biological fitness of H. armigera.

A lectin extracted from Polygonom persicaria (PPA) was mixed with the artificial diet provided to the larvae of Helicoverpa armigera at various concentrations. Although the PPA significantly prolonged larval duration but, decreased pupal weight and larval survival. Nutritional indices such as approximate digestibility, efficiency of conversion of digested food and efficiency of conversion of ingested food were significantly decreased in the PPA-fed larvae. Activities of digestive enzymes in the PPA-fed larvae, such as α-amylase, α-glucosidase, lipase, trypsin, elastase and exopeptidases, were significantly lower than control except for β-glucosidase and chymotrypsin. PPA-fed larvae showed lower amounts of total protein and glycogen compared to control.

The bacterial flora of flour moth and their role in the physiology of Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) were investigated. The gut flora of E. kuehniella was isolated on Luria Bertani Agar (LBA), followed by incubation at 28 °C respectively for 48–72 h. The isolates were identified using 16S rRNA sequencing. Altogether five bacterial species of different genera were identified as Bacillus infantis, Streptomyces cacaoi, Janibacter sp., Stenotrophomonas sp. and Acinetobacter sp. The fourth instar larvae reared on artificial diet without any antibiotic showed higher efficiency of conversion of digested food (ECD) and efficiency of conversion of ingested food (ECI) (16.068 ± 0.568% and 14.455 ± 0.448%), respectively. Approximate digestibility (AD) and Consumption index (CI) of the fourth instars larvae were higher on artificial diets containing tetracycline. The higher activity of alpha-amylase and general proteases were observed in the midgut of larvae reared on artificial diet containing antibiotic chloramphenicol. Total protein and lipid value were higher respectively in larvae that were reared on artificial diet containing streptomycin sulfate and artificial diet containing tetracycline. It seems that antibiotics had no significant effect on enzymatic activities of E. kuehniella. The larvae performed well in tetracycline treatment as per larval developmental duration compared with other treatments. Therefore, the gut bacteria do not seem to play a crucial role in the survival and development of the E. kuehniella. However, the question of adaptation of this pest species to hosts rich in protease inhibitors, such as flour has to be examined and ascertained.

Toxicity and physiological effects of the two components within garlic essential oil, diallyl sulfide, and diallyl disulfide, were studied against the larvae of Tuta absoluta. The larvae treated by dially sulfide showed the LC50 of 0.518% while it was observed 0.390% in those treated by diallyl disulfide. The LT50 values of diallyl sulfide and diallyl disulfide were calculated 9.65 and 7.18 h, respectively. The binary mixture of the given compounds in the different ratios revealed the higher expected mortality than the observed one implying antagonistic interaction against the larvae of T. absoluta. Diallyl sulfide and diallyl disulfide in both LC30 and LC50 concentrations significantly decreased the activities of larval α-amylase, glucosidases, and lipase. The LC50 concentration of diallyl sulfide caused the lower activity of general protease than LC30 concentration but the least activity of general protease was recorded in the larvae treated by both concentrations of diallyl disulfide. Treatment of T. absoluta larvae by both concentrations of dially sulfide and diallyl disulfide significantly decreased the activities trypsin, chymotrypsin, and elastase as well as amino- and carboxypeptidases compared to control. The larval treatment with two concentrations of diallyl sulfide and diallyl disulfide significantly decreased the activity of acetylcholine esterase compared to control in both in vivo and in vitro assays. Diallyl sulfide and diallyl disulfide significantly decreased the activity of alanine aminotransferase compared to control while the highest activity of aspartate aminotransferase was recorded in the larvae treated by LC50 concentration of diallyl disulfide. Dially sulfide and diallyl disulfide significantly decreased the amounts of triglyceride, glycogen, and protein as storage macromolecules compared to control.

Neuropeptides synthesized by insect neurosecretory cells are engaged in several physiological process like immunity, feeding and reproduction so they deserve to be undertaken in subsequent experiments for discovery and manipulation regarding applied objectives. Due to importance of insect ability to utilize plant tissues, the present study was conducted to extract brain peptides in the fifth instar larvae of Pieris brassicae via High performance liquid chromatography and to identify their role in induction of digestive enzyme syntheses. Five peaks were determined and named as fractions 1, 2, 3, 4 and 5. The midguts of starved fifth larval instars were treated by each fraction of brain extract in vitro. The highest activities of α-amylase and lipase were found in the midgut treated by fractions 4 and 1, respectively while the fraction number 5 imposed the highest activities of glucosidases. Fraction 2 led to the highest activities of trypsin, chymotrypsin and elastase as the given serine proteinases as well as the two exopeptidases namely amino- and carboxypeptidases. Moreover, midgut treatments by different concentrations of TLCK (N-p-Tosyl-l-lysine methyl ester hydrochloride), TPCK (Tosyl phenylalanyl chloromethyl ketone), AEBSF (4-(2-Aminoethyl) benzenesulfonyl fluoride hydrochloride) and Acarbose significantly decreased the activities of α-amylase, trypsin, chymotrypsin and elastase by the calculated IC50 values of 0.287, 0.439, 0.288 and 0.361 mM, respectively. The findings demonstrated that different neuropeptides would be engaged in enzymatic release of P. brassicae hence, manipulation of peptide receptors can change physiological process of insects and opens a selective strategy to pest control.

Hyphantria cunea (Drury) has colonized many countries outside its native range of North America and has become a model species for studies of the colonization and subsequent adaptation of agricultural pests. Molecular genetic analyses can clarify the origin and subsequent adaptations to non-native habitats. Using the mitochondrial COI gene, we examined the genetic relationships between invasive populations (China, Iran, Japan, and Korea) and native populations (i.e., the United States). The Jilin (China) and Guilan (Iran) populations showed nine previously unknown haplotypes that differed from those found in the south–central United States, suggesting multiple colonization events and different regions of invasion. A dominant mtDNA haplotype in populations in the United States was shared by all of the populations investigated, suggesting that H. cunea with that haplotype have successfully colonized China, Iran, Japan, and Korea.

There is a rapid growth in the screening of plant materials for finding new bio-pesticides. In the present study, the essential oils of E. oleosa and E. torquata leaves were extracted using a Clevenger apparatus and their chemical profiles were investigated by Gas Chromatography-Mass Spectrometry (GC-MS). Among identified compounds, the terpenes had highest amount for both essential oils; 93.59% for E. oleosa and 97.69% for E. torquata. 1,8-Cineole (31.96%), α-pinene (15.25%) and trans-anethole (7.32%) in the essential oil of E. oleosa and 1,8-cineole (28.57%), α-pinene (15.74%) and globulol (13.11%) in the E. torquata essential oil were identified as the main components. The acaricidal activity of the essential oils of E. oleosa and E. torquata were examined using fumigation methods against the adult females of Tetranychus urticae Koch. The essential oils have potential acaricidal effects on T. urticae. The essential oil of E. oleosa with LC50 value of 2.42 µL/L air was stronger than E. torquata. A correlation between log concentration and mite mortality has been observed. Based on the results of present study, it can be stated that the essential oils of E. oleosa and E. torquata have a worthy potential in the management of T. urticae.

This study attempted to identify a suitable host plant for rearing hybrid 31*32 silkworms. Four varieties of mulberry leaves including Ichinose, Kenmochi, Kines, and local were supplied to hybrid 31*32 of silkworm and their performance was assessed. Variables measured included nutrition, biochemistry, and economic parameters of silkworm. Number of cocoons, individual and total cocoon weight, cocoon shell weight, and cocoon yield/10,000 per larvae were significantly greater on the Kines variety compared with the others. Similarly, nutritional indices including efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD), relative growth rate (RGR), and consumption index (CI) were greater for the larvae fed on Kines. Digestive and antioxidant enzyme activity of the larvae differed with variety. Our results suggest that Kines could be considered as an appropriate host plant for rearing of silkworms based on the study parameters.

In the present study, the toxicity and physiological disorders of the essential oil isolated from Artemisia annua flowers were assessed against one of the main insect pests of mulberry, Glyphodes pyloalis Walker, announcing one of the safe and effective alternatives to synthetic pesticides. The LC50 (lethal concentration to kill 50% of tested insects) values of the oral and fumigant bioassays of A. annua essential oil were 1.204 % W/V and 3.343 μL/L air, respectively. The A. annua essential oil, rich in camphor, artemisia ketone, β-selinene, pinocarvone, 1,8-cineole, and α-pinene, caused a significant reduction in digestive and detoxifying enzyme activity of G. pyloalis larvae. The contents of protein, glucose, and triglyceride were also reduced in the treated larvae by oral and fumigant treatments. The immune system in treated larvae was weakened after both oral and fumigation applications compared to the control groups. Histological studies on the midgut and ovaries showed that A. annua essential oil caused an obvious change in the distribution of the principal cells of tissues and reduction in yolk spheres in oocytes. Therefore, it is suggested that the essential oil from A. annua flowers, with wide-range bio-effects on G. pyloalis, be used as an available, safe, effective insecticide in the protection of mulberry.

The larvae of Ectomyelois ceratoniae Zeller were reared on the artificial diets containing 2% of Citrullus colocynthis L. (Cucurbitaceae) lectin and control to find any changes in gene expression of caspases. Specific primers were designed to amplify genes of six found caspases including Caspase 1, 2, 3, 4, 5 and 6. RNA of both treatments were extracted and cDNA molecules were synthesized prior to gene expression. Results of quantitative real-time polymerase chain reaction revealed that expression of all caspases in the fed larvae by 2% of lectin increased in comparison with control except for caspase 1 as 2.99, 5.7, 17.13, 23.18, 10.44-fold. These results are consistent with our previous studies on the lower activities of digestive enzymes that are due to death of midgut cells followed by binding of lectin molecule.