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The two-spotted spider mite, Tetranychus urticae Koch, is the worst pest for strawberries among all arthropod pests in Iran. In this study, essential oils from the flowering branches and fruits of the chinaberry, Melia azedarach L. were analysed using gas chromatography-mass spectrometry, and the acaricidal activity of the oil was evaluated in fumigation tests against T. urticae. Forty-three constituents were identified and Methanecarbothiolic acid (10.80%), Ethyl Acetate (9.24%), 2-Propanone, 1-fluor (9.01), Acetic acid, 1-methylethyl ester (8.33%) and n-Propyl acetate (8.02%) were the main constituents The mites were susceptible to the oil using the fumigation method. The results stated that M. azedarach oil had high toxicity on eggs and adults of two-spotted spider mite (LC50 was 18.27 and 13.63 µL L−1 for eggs and adults, respectively) with LT50 of 12.05 h. In addition, all tested concentrations had oviposition deterrent activity and repellency on adults of this mite. For the practical use of this oil as a novel acaricide, however, further investigations are needed to evaluate the effects on non-target organisms and the cost-benefit ratio for the formulation of a product to be used on protected crops such as strawberry in the greenhouse condition. [ABSTRACT FROM AUTHOR]

Mites cause significant damage to various crops, often requiring synthetic acaricides for their control. However, the frequent use of these products, resistance problems and severe problems with contamination occur. Therefore, one of the promising solutions is plant acaricides, which can be developed based on essential oils. Thus, the objective of this work was the extraction and characterization of the essential oil from the leaves of Kermani lemongrass, Dracocephalum polychaetum, and acaricidal evaluation of the oil and its major compound using the application by fumigation on female adults of Tetranychus urticae. The composition of the essential oil was analysed by GC-MS. The major components in the oil were 1-octen-3-ol (11.27%), 6-methyl-5-hepten-2-one (11.06%), linalool (9.89), and nonanal (9.64%), respectively. The impact of essential oil of this plant on fumigant toxicity, LT50, oviposition deterrent activity, and repellency against T. urticae was studied at different concentrations. The results stated that D. polychaetum oil had high toxicity on eggs and adults of two-spotted spider mite (LC50 was 60.30 and 50.87 µL L−1 for eggs and adults, respectively) with LT50 of 8.02 h. In addition, all tested concentrations had oviposition deterrent activity and repellency in adults of this mite. [ABSTRACT FROM AUTHOR]

Aphis gossypii Glover (Hemiptera: Aphididae) is one of the most important pests of agriculture worldwide. To control the pest population, research on the use of the environmental and plant-based compounds has increased in recent decades. Essential oils due to volatility and very short-term persistence in the environment, as biocompatible pesticides can be considered as one of the best alternatives to chemical pesticides in aphid's control. In the current study, phytochemical and insecticidal toxicity of the essential oil from Avishan-e-denaii, Thymus daenensis Celak. was studied against the melon aphid, Aphis gossypii Glover. in the laboratory conditions under 25±2°C, 60±5 % RH and 16L:8D photoperiods. The essential oil was obtained by hydrodistillation method, using Clevenger-type apparatus. Mortality was evaluated at different concentrations that ranging from 0.1 to 0.9 μL/L air, and with three replications at the interim of 24 hours. Also nymph production deterrent effect of the oil at sublethal concentration was studied against parthenogenesis form of aphid. Results indicated that essential oil of T. daenensis is toxic to the A. gossypii. The major components in the oil were 3-Methyl-4-isopropylphenol (26.94 %), thymol (22.40 %), p-cymene (13.81 %), γ-terpinene (6.74 %), borneol (5.24 %) and linalool (4.31 %). Probit analysis showed that the LC50 values for nymphs and adults of A. gossypii were 0.0087 and 0.0016 μl./L-1 air, respectively. Also, degree of nymph production deterrent effect was calculated for essential oil of T. daenensis as 46.49 ± 4.71 %. The overall results showed that the Avishan-e-denaii essential oil has high potential in controlling the melon aphid especially in protected cultivation. [ABSTRACT FROM AUTHOR]

Tuta absolutais one of the key pests of Solanaceae family in the world. This insect is an oligophagous pest and its larva causes damage on the host plants by feeding on leaf, stem and fruit of them. In the current study, chemical composition and insecticidal activities of the essential oil from cardamom,Elettaria cardamomumon egg, the 2nd larval instars and adults of T. absoluta were evaluated. Results indicated that oil is toxic to the T. absoluta. The major components in the oil were as follow: terpinenyl acetate (36.61%), 1,8-cineole (30.42%), linalyl acetate (5.79%) and sabinene (4.85%). LC50 values for eggs, larvae and adults were 351.19, 7.88, 1.55 and 1.88 μl L−1air, respectively. The tomato leaf miner (TLM),T. absoluta(Meyrick) (Lepidoptera: Gelechiidae), is a important pest on tomato, potato and other Solanaceous with a huge economic importance. TLM can be regarded as a serious threat to tomato production in Iran. TLM larvae cause about 100% losses by attacking tomato leaves, flowers, stems and especially fruits. The discovery of active compounds that are less persistent will be beneficial to both the environment and agricultural product consumers. Management of the pest can be problematic, especially when the infestation pressure is high. The utilization of natural compounds such as plant essential oils is considered as a alternatives to chemical pesticides because of their lower toxicity on the non-target and low persistence in the environment. In the present study, the chemical composition and insecticidal activities of the essential oil from cardamom,E. cardamomum(Maton) (Zingiberales: Zingiberaceae) on egg, the 2nd larval instars and adults ofT. absolutawere evaluated. The essential oil was obtained by hydrodistillation method, using a modified clevenger-type apparatus. Experiments were performed at 27 ± 2 °C, 65 ± 5% RH and 16 L:8D h photoperiods. Results showed that the essential oil ofE. cardamomumis toxic toT. absoluta. The major components in the oil were α-terpinyl acetate (36.61%), 1,8-cineole (30.42%), linalyl acetate (5.79%) and sabinene (4.85%). Probit analysis showed that the LC50values for eggs, 2nd larval instar (inside leaf, outside leaf) and adults were 351.19, 7.88, 1.55 and 1.88 μl L−1air, respectively. The overall results showed that cardamom essential oil has high potential in controlling TLM, especially in protected areas. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite,Tetranychus urticaeKoch, one of the major pests of various agricultural plants, causes many problems with agricultural, horticultural and ornamental plants. In recent years, using plant-derived compounds such as essential oils and extracts were attended to their insecticidal and acaricidal properties. The galbanum,Ferula gummosais a native plant of central Asia, was identified as an acaricide plant for the first time of this study. The composition of the essential oil was analyzed by GC-MS. The major components in the oil were β-pinene (50.1%), α- pinene (14.9%) and δ-3-Carene (6.7%). The impact on essential oil of this plant on fumigant toxicity, LT50, oviposition deterrent activity and repellency againstT. urticaewas studied at different concentrations. The results stated thatF. gummosaoil had high toxicity on eggs and adults of two-spotted spider mite (LC50was 6.98 and 6.52 μL L-1for eggs and adults, respectively). In addition, all tested concentrations had oviposition deterrent activity and repellency on adults of this mite. [ABSTRACT FROM PUBLISHER]

The cabbage aphid, Brevicoryne brassicae L. is one of the most important pests of Brassicaceae family. Plant essential oils contain compounds that showed ovicidial, repellency (anti-feeding), unproductive and toxic effects on insects. In this research, insecticial activity and nymph production deterrent of five essential oils was studied on the cabbage aphid in the laboratory conditions under 25 ± 2°C, 65 ± 5% RH and 16L:8D photoperiods. Mortality was evaluated at six different concentrations that ranging from 0.71 to 226.67 μL/L air, and with 6 replications at the interim of 24 hours. The results showed that by increasing dose and time, mortality rate was also increased. The highest and the lowest mortality rate were recorded for Elettaria cardamomum and Citrus sinensis, respectively. Also the highest deterrence percentage is related to LC10forE. cardamomum and the lowest belonged to LC10forC. sinensis and Cinnamomum zeylanicum. It can be concluded that essential oil of E. cardamomum is an appropriate mix and can be used for control of the cabbage aphid in integrated pest management methods. [ABSTRACT FROM AUTHOR]

Nowadays, usage of pesticides is one of the primary methods in aphids control and have an important role in pest control, but improper use of them are causing adverse effects on non-target organisms and the environment. Essential oils due to volatility and very short-term persistence in the environment, as biocompatible pesticides can be considered as one of the alternatives to chemical pesticides in aphid’s control. This study was conducted to determine the insecticidal activity and nymph production deterrent of three essential oils from Savory,Satureja isophyllaRech., Cinnamon,Cinnamomum zeylanicumBlume. and Fennel,Foeniculum vulgareMill. againstBrevicoryne brassicaL. and the black aphid,Aphis fabaeScop. (Hemiptera: Aphididae) under laboratory conditions 25 ± 2°C, 65 ± 5% RH and 16L:8D photoperiods. Mortality was evaluated at different concentrations that ranging from 0.71 to 282.35 μL/L air, and with 6 replications at the interim of 24 hours. The results showed that essential oils have toxicity both aphids. Oils toxicity effect onA. fabaewas more thanB. brassicaeand also the highest deterrence effect was related to Fennel essential oil onB. brassica. [ABSTRACT FROM PUBLISHER]

Today, to control of stored-product pests the gaseous chemical compound is usually used. These compounds do not have deleterious effects on non target organisms, environment pollutions, insect's resistance, toxicity to humans and other mammals. In recent years, plants essential oils have received much attention because of their insecticidal, oviposition deterency, repellent effects and antifeedant properties. This study was carried out to evaluate the repellent effects of essential oils from Laurus nobilis and Myrtus commonis against adults of Ephestia kuehniella Zeller (Lep: Pyralidae). Each essential oil consists of five concentrations and each concentration was repeated five times. Bioassays experiments were performed in 25°C, 65 ± 5 RH and in the dark period at the laboratory condition. The result showed that, repellency rate of this pest was significantly increased by essential oils. Repellency power of both essential oils was increased with increase of oil concentrations. Around 20.4 and 10.6% repellency rates was observed at the lowest concentration (0.50 µl.L-1 air) of L. nobilis and M. commonis, respectively. Also at the highest concentration (2.00 µl.L-1 air) repellency rates were reached to 84.2% by L. nobilis and 61.3% related to M. commonis. As a result, it could be concluded that essential oils from L. nobilis and M. commonis have considerable repellent effects on E. kuehniella even at low concentrations. [ABSTRACT FROM AUTHOR]

Two-spotted spider mite,Tetranychus urticaeKoch is the major pest of various plants worldwide. Now the control is dependent on the use of chemical pesticides. Plant compounds are recently known as biopesticides. Essential oil ofElettaria cardamomumwas researched on repellent and oviposition inhibition ofT. urticae. The LC50values of fumigant toxicity of this oil on adults and eggs of the two spotted spider mite were 7.26 and 8.82 μL/L air, respectively. Also LT50value of essential oil at 45 μL/L air was 23.86 h and LT50value of essential oil at 60 μL/L air was 9.01 h. In addition, different concentrations of the essential oil ofE. cardamomumsignificantly affected oviposition deterrence and repellency of adults. The results of this study indicated that essential oil ofE. cardamomummay be considered as a biopesticide to control two spotted spider mites. [ABSTRACT FROM PUBLISHER]

Two-spotted spider mite,Tetranychus urticaeKoch, is one of the most important pests of agricultural products that have a global distribution. Now, the control is dependent on the use of chemical pesticides. The effects of the sublethal concentrations (LC10and LC25) of the essential oil ofCinnamomum zeylanicumwere evaluated on some parameters of the life table of the pest, at the constant temperature of 30 °C, relative humidity of 40 ± 5% and photoperiod of 16L: 8D. Our results showed that the essential oil of cinnamon is effective on female adult stage. Lethal concentration at which 50% mortality (LC50) for the essential oils is fromC. zeylanicumon female adult mite was 23.39 μl/L air. Sublethal concentrations of the essential oil ofC. zeylanicumalso impair the natural biology of the mite. Concentrations of sublethal of essential oil decreased age-specific fertility (mx) ofT. urticaecompared with the control. Sublethal concentrations (LC10and LC25) have reduced the life expectancy (ex) in egg stage. Sublethal effects of the essential oil ofC. zeylanicumand its impact onT. urticaemanagement are discussed. [ABSTRACT FROM PUBLISHER]

The article focuses on a research conducted in order to evaluate fumigant toxicity, oviposition deterrency and insecticidal activities of the essential oil obtained from Elettaria cardamomum (E. cardamomum) on the adults of three stored product pests. It discusses the analysis of the chemical constituents of the essential oils using gas chromatography-mass spectrometry. The study revealed that the essential oil of E. cardamomum is toxic to the bruchid beetle and the red flour beetle.

Plant materials with insecticidal properties have been traditionally used for generations in some parts of the world. In this study, fumigant toxicity of some essential oils extracted from Rosmarinus officinalis L., Mentha pulegium L., Zataria multiflora, and Citrus sinensis (L.) Osbeck var. hamlin on adults of stored-product pests, including Tribolium castaneum, Sitophilus granarius, Callosobruchus maculatus, and Plodia interpunctella were investigated. Pure essential oils were used in glass vials for the bioassay. LC50 values of Citrus sinensis var. hamlin against T. castaneum, S. granarius, and C. maculatus were 391.28, 367.75, and 223.48 µL L-1 air after 24 h, 362.40, 20.45, and 207.17 µL L-1 air after 48 h, respectively. Furthermore, LC50 values of the fumigant test of C. sinensis and M. pulegium essential oils against S. granarius were 0.038 and 367.75 µL L-1 air after 24 h, 0.025 and 320.45 µL L-1 air after 48 h, respectively. On the other hand, LC50 values of R. officinalis and Z. multiflora on P. interpunctella moths were 0.93 and 1.75 µL L-1 after 24 h. Results showed that among tested essential oils, C. sinensis var. hamlin had good fumigant toxicity on T. castaneum, S. granarius, and C. maculatus. In addition, M. pulegium essential oil was stronger than C. sinensis var. hamlin on S. granarius. Results also indicated that both Z. multiflora and R. officinalis had fumigant toxicity on P. interpunctella adults. In summary, results indicated that these essential oils have good fumigant toxicity on stored-product pests. [ABSTRACT FROM AUTHOR]