مریم نگهبان

The red flour beetle (Tribolium castaneum (Herbst)) (Tenebrionidae) is one of the main pests of stored products, especially cereal crops, all over the world. In recent years, to reduce the use of chemical pesticides, plant essential oils have gained attention. But despite their good potential, essential oils are unstable, and their toxicity decreases in a short time after use. Nanocapsule formulations can improve the efficiency of plant essential oils on stored product pests by increasing their toxicity and durability. This study was carried out with the aim of preparing nanocapsule formulations of essential oils of Eucalyptus camaldulensis Dehnh. and Eucalyptus globulus Labill. and comparing their fumigant toxicity effects and non-formulated essential oils on T. castaneum adults.

 Eucalyptus leaves were collected from the Zaghmarz Eucalyptus research station in the south of Behshahr city, Mazandran Province, in July 2018. The collected dried leaves of Eucalyptus were hydrodistilled using a Clevenger-type apparatus. Identification of the constituents of essential oils was performed using GC-MS. Sodium alginate nanocapsules were prepared using basic hydrophilic surfactants. The survey of the surface and wall morphology of nanocapsules was conducted using a transmission electron microscope. The particle size distribution of nanocapsules was also determined. Fumigant toxicity testing was performed separately for each essential oil and nano-capsulated essential oil in four concentrations and at 24, 48, and 72 hours after applying the treatments, along with the control at 25°C and a relative humidity of 65% in darkness. PoloPlus software was used to estimate the LC10, LC25, LC50, and LC95.

 According to the results, the number of compounds in the essential oils of E. globulus was higher. The most important compounds of the essential oils of the two Eucalyptus species were terpenes, and 1,8-cineole, limonene, and pinene-α were the most important terpenes in the essential oils of E. globulus and E. camaldulensis, respectively. The results obtained from the transmission electron microscope images showed that nanocapsules containing Eucalyptus essential oil have nanoscale dimensions. The average particle size distribution for E. globulus and E. camaldulensis essential oil nanocapsules was determined to be about 150 and 100 nm, respectively. The essential oil of E. globulus was more toxic than the essential oil of E. camaldulensis. The values of LC50 at 24, 48, and 72 hours after treatment for essential oil nanocapsules of E. globulus and E. camaldulensis were 5.9, 4.63, 3.8, and 9.5, 8.67, 6.7, respectively, and LC50 for raw essential oils of E. globulus and E. camaldulensis were 10.93, 9.63, 5.7, and 15.09, 12.86, 8.2 ml per liter of air, respectively. Based on the results, the nanocapsule formulation of the essential oils of both species, compared to the raw essential oil, showed a decrease in LC50, and the durability of the encapsulated essential oil also increased.

 Based on our results, nanoencapsulation of Eucalyptus essential oil increased the fumigant toxicity of the essential oils by enhancing toxicity and the controlled release of effective compounds in controlling this pest. Therefore, this nanocapsule formulation is recommended for further toxicity tests and eventually its use in storage.

The greenhouse whitefly, Trialeurodes vaporariorum Westwood, is one of the most destructive greenhouse pest in the world. In this study, the lethal and sublethal effects of Mentha piperita L. essential oil and its nanoformulation were investigated on the T. vaporariorum by considering the biological and population growth parameters. Extraction of essential oil was done by steam distillation using clevenger, and the chemical components of M. piperita were evaluated by gas chromatography-mass spectrometry. The results showed that monoterpenoids including carvone (%57.13) and limonene (%26.90) were the main characterized components of pipermint essential oil. The characterization of nanoformulation was done using dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results showed that the nanoemolsion was spherical in shape with the average sizes of 179.74 nm. The leaf dipping was used for the bioassays. The bioassay results showed that, the nanoformulation of eesential oil (LC50: 3375.411 ppm) was more toxic than the pipermint (LC50: 4536.118 ppm) on the T. vaporariorum adults. The life table data were analyzed based on the age-stage, two-sex life table theory. Also, the sublethal concentration (LC25) of pipermint nanoformulation affected life table parameters of T. vaporariorum by prolonging the developmental time of T. vaporariorum, decreasing the female longevity and fecundity compared with essential oil. Also, the population growth parameters such as intrinsic rate of increase and finite rate of increase treated by nanoemolsion of essential oil (0.076±0.006 day -1) and (1.079±0.007 day -1) were lower than the essential oil (0.084±0.006 day -1) and (1.087±0.006 day -1), significantly. The total results showed that pipermint,s nanoformulation has the most lethal and sublethal effects on greenhouse whitefly compared with the pured form of essential oil which can be consider in integrated pest management program (IPM) of this pest.

Eggplant greenhouse cultivations in last two /three years found under progressing and intensive spider mite damages observed for the first time in Varamin region.  Effects of two new botanical pesticides, Mariapro+Coverino-M, Bio-2, in comparison of propargite 57% EC and tetradifon v/w 7.52% were evaluated against Tetranychus urticae red color population on round black eggplants variety 1574 in greenhouse during spring season of 2021 in Varamin region. Spraying of treatments done with wheel burrow sprayer and effects of the them carried out by random 15 leaves collected from each treatment at one day before and 3,7and 15 days after. Mite active stages on 2cm2 on middle under side of eggplant leaf recorded by help of stereomicroscope. Abbott formula used to convert raw data in to mortality%. Mean mite mortality% of treatments analyzed with SAS software. Minimum and maximum mean active mite stages for 2ml/l Tetradifon (25.83 mites) and 1.5 ml/l of Bio-2 (44.50 mite) recorded respectively. Pesticide control effects showed a statistical significant (p<0.05) at different interval times. Higher effects (100%) for both propargite doses recorded at 3rd and 7th day of interval periods and least mortality% (58.92%) observed for tetradifon 2ml/l at 15 days’ interval time. Low slop mite mortality% found at decreasing level until 15 days for most of treatments. Spraying old registered acaricides recommended at higher spider mite infestation before harvesting period. Both new botanical pesticides can provide mite control damages during eggplant fruiting time and producing organic vegetables under greenhouses.

According to the recent advances in the application of biotechnology in various sciences, in recent years, research has been conducted in the field of preparation of liquid bioformulations and microcapsules of suspension and powder from the important fungal inhibitor Talaromyces flavus. In this study, optimization of the mentioned formulations and their use in commercial greenhouses have been done. For this purpose, based on the results of previous greenhouse research, regarding the preparation of a type of liquid bioformulation (liquid formulation containing Potato Dextrose Broth culture medium, temperature of 25 degrees Celsius and dicycloserine or sodium nitrate stabilizer), a type of microcapsule in the form of suspension. A type of microcapsule in powder form was prepared for use in tomato greenhouses. To optimize the liquid formulation, the most suitable emulsifiers and binders in terms of suspensionability were identified as Tween 20 and carboxymethyl cellulose. For the optimization of suspension and powder microcapsules, the most suitable combination of polymer + surfactant in terms of solubility was determined, respectively, the combination of alginate + myristyl alcohol and guargam + calcium lignosulfate. Investigations related to commercial greenhouses were carried out during one year in two regions of Yazd and Isfahan with a history of Fusarium wilt disease. Each study was carried out in the form of a statistical design of complete randomized blocks with eight treatments in four replications. The treatments were: 1 to 3– each of the liquid formulations, suspension microcapsules and powder microcapsules with the method of adding to the soil, 4 to 6– each of the mentioned formulations with the root immersion method, 7– Thalaromin fungicide By the method of adding to the soil, 8– control (without application of formulation and fungicide). The treatments were evaluated by determining the percentage of occurrence and the percentage of severity of fusarium wilt disease. Statistical data analysis and mean comparison was done using Duncan's multiple range test by MS TAT C software program. The results showed that the microcapsule powder with the seedling impregnation method and the liquid formulation with the soil addition method were the most effective treatments by reducing the disease severity percentage by 91.6 and 68.4%, respectively, compared to the control. According to the results Obtained, the method of producing and using each of Talaromyces flavus microcapsule and liquid formulations is considered as technical knowledge and it is possible to proceed with their commercialization steps.

Nowadays, the invention and application of agricultural pest control non-chemical methods is one of the important and practical ones in pest management programs in most societies of the world. Meanwhile, a large number of studies have been focused on bio-based pesticides. In this regard, new formulations of plant insecticides have been developed as a suitable alternative to artificial pesticides. In this research, respiratory and contact toxicity of pure and formulated Eucalyptus globulus Labill. essential oil and respiratory toxicity durability of its essential oil nanocapsules on adult insects of Tribolium confusum Herbest. (Col., Tenebrionidae) were investigated under laboratory conditions. According to the results, for respiratory toxicity, the pure and formulated essential oil LC50 at 24 h was obtained 46.39 and 1472 μl.l-1 of air, respectively. The formulated essential oil LT50 in three concentrations of LC25, LC50, and LC90 was determined 12.3, 10.39, and 0.36 days, respectively. The results also showed that the contact toxicity of formulated essential oil (LC50= 19030 μl.l-1) on this insect was much higher than the contact toxicity of pure one (LC50= 3770 μl.l-1). Therefore, due to the good stability of the formulated essential oil in respiratory toxicity and the excellent effect in contact toxicity, after additional tests, eucalyptus essential oil nanocapsules could be used in the management of this important pest.

The efficiency of powder microcapsules and suspension microcapsules of Talaromyces flavus with concentrations of 106 × 2, 106 × 4, 106 × 6, 106 × 8 and 107 colony forming units per gram of formulation in soil addition method and a concentration of 107 colony forming units per gram of formulation in seed impregnation method was compared with registered fungicide Talaromin in two methods of seed impregnation and addition to soil to control Fusarium wilt disease of tomatoes. The results showed that the most effective treatments were related to the different concentrations of suspension microcapsules by soil addition method and powder microcapsules by seed coating method and the highest concentration (107 colony forming units per gram) in adding to soil method reduced significantly 83- 96% the severity of the disease compared to the infected control.

Leukemia is one of the most important diseases that affected human lives. Therefore, study of effective factors in order to control of this disease is very essential. This study was investigated the effect of cytotoxicity of extracts (n- Hexane, Diethyl ether, Methanol) from the algae Padina tenuis  Bory de Saint-Vincent on leukemia cell line. For this purpose, the required extracts of Padina tenuis  Bory de Saint-Vincent were prepared by rotary which was collected from the Namakdan rocky shores, Qeshm Island. Subsequently, human leukemia cell line was cultured in RPMI culture medium with 10% fetal bovine serum. The cytotoxic effect of different concentrations (10, 30, 75, 150, 300, 500 µg / ml) was measured by MTT method. Hexane, diethyl ether and methanol extracts were able to inhibit the proliferation of human leukemia cells at 258 µg / ml, 90 µg / ml and of 122 µg /ml concentrations, respectively, in vitro. Also, with increasing the concentration of extracts, the percentage of metabolic activity of cancer cells decreased. The results showed a significant difference in the effect of different solvents against blood cancer cells at a significance level of 95%

Nowadays, extensive research is being done on plant compounds to find safer and low-risk alternative for controlling pests. In this study, two formulations, containing Artemisia sieberi Besser essential oil based on biodegradable polymers were prepared as powders to control the rice weevil, Sitophilus oryzae. These formulations were different in the amounts and types of polymers and surfactants. The repellency effect of these formulations and A. sieberi oil was compared at two sublethal concentrations of 5 and 10 µI/I air. The surface morphology of powders was also studied by the transmission electron microscope (TEM). The average size of particles was measured about 41.19 and 37.86 nm for formulations 1 and 2, respectively, using the software Image j. The result shows that, after 96 hours, the percentage of repellency in essential oil, formulation 1 and formulation 2 for 5 ppm concentration is calculated 45%, 65% and 70% respectively, and for 10 ppm concentration it is calculated 55%, 70% and 75% respectively. Also, the repellency effects of normal essential oil and the formulations prepared at different times showed that with increasing the concentration of all compounds, the amount of repellency increases. Based on the results, to maintain the biological activity of essential oils and prevent the evaporation of their constituents, it is necessary to formulate essential oils, therefore encapsulation of plant essential oils as a safe pesticide with gradual release and maintenance of fumigant toxicity can be considered in integrated pest management.

Plant essential oils are secoundary metabolites that protect the plants against wide range of arthropods and plant pathogens. Encapsulation of essential oils can improve their stability and efficacy for pest control. In this study, the essential oil of Thymus daenensis Celak. (Lamiales: Lamiaceae) was extracted using hydro-distillation, and urea-formaldehyde nanocapsule of the essential oil was then prepared using in situ polymerization technique. In addition, the effects of sublethal concentrations (LC25) of pure and nanocapsulated formulations of T. daenensis essential oil on the life-table parameters of Brevicoryne brassicae L. (Hem.: Aphididae) were examined using leaf-dipping method under laboratory conditions. According to the obtained results, the intrinsic rate of increase (r) was 0.16, 0.21, 0.29 and 0.29 day-1 for nanocapsulated formulation, pure formulation, 1st control (distilled water + Tween 80 (0.5%)) and 2nd control (distilled water), respectively. The finite rate of increase (λ) was also significantly lower for aphids treated by nanocapsulated formulation (1.17 day-1) than aphids in pure formulation treatment (1.24 day-1), and 1st (1.34 day-1) and 2nd (1.33 day-1) control groups. Furthermore, the net reproductive rate (R0) was 5.24 and 9.84 nymphs for nanocapsulated and pure formulations, respectively, which were significantly lower than that for controls. The greatest and lowest mean generation time (T) were observed for the 2nd control (11.25 days) and nanocapsulated formulation (10.32 days), respectively. According to findings of this study, the nanocapsulated formulation of T. daenensis essential oil is recommended for use in the integrated pest management of B. brassicae.

Nowadays, nanoemulsions are considered by many researchers because of their unique physiochemical properties such as small particle size, long-term physical stability and transparency. In this research, fumigant toxicity of Mentha longifolia L. essential oil and its nanoemulsion against Callosobruchus maculatus (Fabricius) has been studied. The experiments were conducted at laboratory conditions at 27±2°C temperature, 65±5% relative humidity and darkness. Essential oil of M. longifolia had higher fumigant toxicity than nanoemulsion, during early hours after treatment. The LC50 values of oil and nanoemulsion for the adults of the pest were 10.1 and 16.1 µl/l, respectively. The values of LC50 were 4.9 and 9.4 µl/l for oil and nanoemulsion during incubation period, respectively. In concentration of 25 µl/l, LT50 of M. longifolia essential oil and nanoemulsion were 2.2 and 11.1 days, respectively. In concentration of 10.1 µl/l, essential oil did not have durability, but this parameter of nanoemulsion is good (LT50= 9.04 days). At 9 µl/l of essential oil, the average time for the mortality of 50% eggs was 4.7 days. The LT50 of nanoemulsion at this concentration was 17.09 days. At 4.9 µl/l of nanoemulsion, the LT50 was 12.8 days, while essential oil did not have durability. The average diameter of nanoemulsion particles has been estimated about 10-36 nm by using transmission electron microscope (TEM). By using laser light scattering (SEMATech), this value was 234 nm. Considering obtained results, using nanoemulsion form of M. longifolia essential oil increase its fumigant toxicity and durability.

In this study, the nanoemulsion containing Mentha longifolia essential oil was produced by using high-pressure homogenization method and its fumigant toxicity was compared with ordinary M. longifolia essential oil on different stages of Ephestia kuehniella. Experimental conditions were as follows; 27±1 °C, 70± 5% relative humidity in total darkness. Concentrations of 111.1-1111.1 and 62.9-92.6 µl/l air of oil have been used to control larva and eggs, respectively. Nanoemulsion concentrations were studied at 122.2-1111.1 µl/l air for larvicide experiment and 81.4-114.8 µl/l air for ovicidal stage. PT50 value at 1111.1 µl/l air as a larvicide for nanoemulsion and oil was estimated about 15.18 and 3.69 days, respectively. This value, at 92.6 µl/l air on egg was 14.44 and 2.58 days, respectively. The relative median potency parameter (RMP) showed that there was significant difference between PT50 values of essential oil and its nanoemulsion on both of the two stages of pest. Results showed that nanoemulsion containing M. longifolia oil can release slow properties lead to durability of fumigant toxicity of oil in the long term. Therefore, this new formulation could be considered as a new and ecofriendly biopesticide in pest control.

In recent years, different formulations such as nanoemulsions have been widely used for the target delivery, and enhanced biological functions of pesticides combinations. In this study, contact toxicity of Mentha longifolia L. essential oil compared with its nanoemulsion on Ephestia kuehniella Zeller has been investigated. The experiments were conducted and executed at 27 ± 1 °C, and 75 ± 5% relative humidity under dark conditions. Chemical composition of this plant extract was also studied. The main constituents were pulegone (28.84%), 1,8-cineol (19.6%), p-menthan-3-one-cis (8.2%), β-pinene (6.46%) and p-menthan-3-one-trans (5.86%). Results indicated that the mortality rate of 5th instar larva of E. kuehniella increased with rising concentrations (10000-40000ppm) for oil and (8000-20000 ppm) for nanoemulsion, respectively. The essential oil LC50 was 21352ppm, while this value for nanoemulsion was 14068ppm. According to the results, nanoemulsion was more effective than essential oil. M. longifolia oil had lower durability and the 50% persistent time (PT50) was 2.39 day compared to the nanoemulsion (PT50 = 17.13 day) in the highest concentration of essential oil. The nanoparticle size was 14-36 nanometers (nm) when the transmission electron microscope (TEM) was applied. The surface morphology of nanoemulsion was also studied by TEM. The average size of the particles was estimated 234nm by using laser light scattering apparatus. The overall results of this study show that by using nanoemulsion formulation, the effect of essential oil contact toxicity and its durability increases. Hence, the nanoemulsion slow-release formulation may represent a new category of biopesticides and this should be considered in the integrated pest management program.

The elm leaf beetle, Xanthogaleruca luteolla, is the most important pest of elm trees, which causes severe damages every year. Chemical control is used as one of the most important methods of management of the pest extensively. Due to the deleterious effects of chemical pesticides on non-target organisms, beneficial insects and the environment, the use of botanical pesticides would be a safe and suitable method for the pest control. In this study, the contact and feeding toxicity of a new botanical pesticide, named Dayabon (SL10%), was evaluated on the 2nd instar larvae, 3rd instar larvae and adults. A preliminary experiment was conducted to estimate concentrations to cause 20 and 80 percent mortality. The bioassay was designed to determine LC50 values of 24 h post treatments. LC50 of Dayabon was estimated to be 5154, 6272 and 3928 ppm, after spraying (leaf and insect) on the 2nd instar larvae, 3rd instar larvae and adults, respectively. Treatment of leaves caused 20%, 40% and 60% damage reduction in the 2nd, 3rd instar larvae and adults compared with control at 5000, 6000 and 4000 ppm, respectively. Findings of this study indicated the possibility of practical use of Dayabon in management of elm leaf beetle in urban landscape.

Citrus red mite, Panonychus citri McGregor is one of the most important pests of citrus orchards in the world. Due to excessive use of chemical pesticides and development of resistance plus their increasing environmental hazards, the use of essential oils has been highly studied. But the low solubility of essential oils in water, oxidation, in addition to their instability in presence of light, humidity and high temperature has diminished their application. Formulation technology is one of the main strategies that can modify the physical properties and the viability of the essential oils in agricultural pest management programs. In this research, the essential oil of Cuminum cyminum L. was encapsulated by in situ polymerization of oil/water emulsion in nano scale and then the effects of nanoencapsulated essential oil (NEO) were analyzed against P. citri. The results showed that LC50 of NEO's contact toxicity was 743.17 ppm over 24 hours. NEO also affected mortality and decreased oviposition rate in P. citri. NEO had deterrence capacity at 300, 500 and 700 ppm. Moreover, NOE had oviposition deterrence, lowering the number of eggs per female compared to the control. Our finding suggests that high-tech formulations including nanoencapsulation technology can be used as botanical pesticides and as alternatives to chemical pesticides.

Nowadays, the use of nanoencapsulation technology of pesticides causes increase in efficiency and controlled release of these substances. In this study, the antifeedant and repellent activities of nanoencapsulated formulation (NEF) of wormwood sagebrush Artemisia sieberi Besser essential oil wereinvestigated against the elm leaf beetle Xanthogaleruca luteola (Muller). The experiments were conducted at 25 ± 2 °C, 65 ± 5% RH and a photoperiod of 16:8 h (L: D). NEF decreased the nutritional indices significantly compared to non-formulated oil.. NEF at a concentration of 4000 ppm, reduced efficacy of conversion of ingested food and efficacy of conversion of digested food in larvae, twice lower compared to pure essential oil. The repellency of non-formulated essential oil at a concentration of 8000 ppm reached it’s highest level after 6 h exposure, while the repellency of NEF increased over time and reached to 100% after 24 h and continued for 72 h. Therefore, further investigations are necessary to consider the NEF made by the A. sieberi essential oil as an effective toxicant against the elm leaf beetle.

New formulations of botanical insecticides have been developed as an effective and safe compound alternative to synthetic pesticides. Application of nanoencapsulated formulations of pesticides enhance efficiency, quality and controlled release of these substances. In this research, insecticidal activity of essential oil of wormwood sagebrush Artemisia sieberi Besser was investigated on various stages of elm leaf beetle Xanthogaleruca luteola (Müller). The experiments were conducted at 25 ± 2 °C, 65 ± 5% RH and a photoperiod of 16: 8 h (L: D). The formulated essential oil was sprayed on leaves and insects simultaneously. The LC50 value of the formulation was 5279, 3939 and 5169 ppm for eggs, larvae and adults, respectively. Treatment of leaves by nanoencapsulated oil at 3000 ppm caused significant reduction at larval stage compared to control. Our findings suggest that the use of nanoencapsulated essential oil can be effective in the management of elm leaf beetle.

Recent research has focused on insecticidal property of essential oil plants in biological control of insects. Controlled release by nanoencapsulated essential oil seems to be the best choice for increasing the efficiency and minimization of environmental damage. In this work, efficiency of nanoencapsulated essential oil of Artemisia sieberi Besser was tested on repellent activity of Plutella xylostella L.. Several concentrations were prepared and then third instars larvae were introduced into each treatment. Then, repellent activity was determined after 1, 3, 6, 12 and 24 h from commencement of exposure. Results showed that at 1.9 ppm the nanocapule of Artemisia oil was shown here to possess more repellent activity (80%) to P. xylustella compered to Artemisia oil (62%) before formulation after 24h. The repellent activity varied with application method and concentrations and exposure time. The results showed higher repellent rates in nanocapsule than in essential oil due to controlled-release formulations allowing smaller quantities of essential oil to be used more effectively over a given time interval. The reasons for nanocapsulating the essential oil have been to improve its stability to reduce side effects or to reduce dosing frequency and total dosing amount, to obtain better repellent activity, and for sustained (long-lasting) release. Therefore the nanocapsulation of A. sibeiri might provide a new method for the management of P. xylostella.

Controlled release by nanoencapsulated formulations allow the essential oil to be used more effectively over a given time interval, suitability to mode of application and minimization of environmental damage. In this work, efficiency of nanoencapsulated essential oil of Artemisia sieberi Besser was tested on nutritional indices of Plutella xylostella L. Several experiments were designed to measure the indices such as Relative Growth Rate (RGR), Relative Consumption Rate (RCR), Efficiency of Conversion of Ingested food (ECI), Efficiency of Conversion of Digested food (ECD), Approximate Digestibility (AD) and Feeding Deterrent Index (FDI). Treatments were evaluated by the method of leaf disk bioassay at 25 °C, 65±5% RH, and a photoperiod of 16:8 h (Light: Dark). Ten third-instar larvae were introduced into each treatment containing different concentrations of the essential oil. Then, ingested food and weight gained were measured after 24, 48 and 72 h intervals. Results showed that nanocapsule of A. sieberi oil was highly effective compared to control (A. sieberi oil), and significantly decreased the RGR ECI, ECD and AD. Moreover, findings indicated a post-ingestive toxicity of the essential oil using the nanoencapsulated formulation. As a result, this nanoencapsulated essential oil tested merits further study as potential insecticide for the control of P. xylostella.

In order to increase the efficiency of essential oils، the use of formulations with controlled release of the oil encapsulated in micro- and nano-scales would be the best option. In this research، the antifeedant activity of nanoencapsulated essential oil of Carum copticum C. B. Clarke was investigated on Plutella xylostella (L.) larvae. To determine the nutritional indices of the larvae affected by the formulated essential oil، weight of ingested food، larval biomass and weight of feces produced were recorded daily for three days. The experiments were conducted at 27 ± 1°C، 65 ± 5% RH and photoperiod of 16:8 h light: dark. Results indicated a significant decrease in nutritional indices such as relative consumption rate، relative growth rate، efficacy of conversion of ingested food and efficacy of conversion of digested food as concentration of the oil increased. Moreover، digestibility was decreased significantly، 72 h after feeding. However، feeding deterrence index was not significantly increased as compared with control. The finding led to a conclusion that nanoencapsulated oil has potential to control release of the essential oils and increase in post-ingestive toxicity of the insect.

In regard to the invasion of various food commodities by insects and harmful effects of chemical pesticides, essential oils are among the best known substances tested against stored product pests. Effects of essential oils from Artemisia sieberi Besser and Artemisia scoparia Waldst et Kit were tested against oviposition deterrence, egg hatching and first instar larvae of Callosobruchus maculatus F. at 27 ± 1˚C and 65 ± 5% R.H. under dark condition. For each essential oil, five replications were conducted. Increasing the essential oil concentrations resulted in increase if insecticidal activity of essential oils on eggs, first instar larvae and oviposition deterrence. At 0.14 mL/g food, the essential oils of A. sieberi and A. scoparia resulted in inhibition of oviposition of the insect. The maximum concentration of essential oils (2.86 mL/L air) caused 100% mortality of first instar larvae. Although, oviposition deterrence of A. scoparia was stronger than A. sieberi, however, ovicidal and larval mortality caused by both essential oils were not significantly different. LC50 values indicated that essential oil of A. scoparia with 1.11 and 1.06 mL/L air against eggs and first instar larvae do not have significant difference with A. sieberi. It was found that plant essential oils can be used as a safe pesticide or model for new synthetic pesticides to control stored pests.

Efficiency of essential oils from Artemisia sieberi Besserand A. scoparia Waldst et Kiton nutritional indices of Tribolium castaneum Herbst was tested in this study. Several experiments were designed to measure the indices such as relative growth rate (RGR), relative consumption rate (RCR), efficiency of conversion of ingested food (ECI) and feeding deterrent index (FDI). Treatments were evaluated by the method of flour disk bioassay in the dark, at 27 ±1 0C and 65 ±5% R. H. Several concentrations of 0, 0.1, 0.5, 0.75, 1, 1.5 and 2 mL/disk were prepared from each essential oil and 10 adult insects were introduced into each treatment. Then, ingested food and weight gained were measured three days later. Results showed that A. sieberi oil was highly effective compared to A. scoparia, and significantly decreased the RGR and RCR. Moreover, in higher concentration (2 mL/disk), the ECI (9.81%) was significantly low. The A. sieberi oil was more effective on FDI than A. scoparia.