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In this research, the efficacy of plant extract from Datura stramonium L. (Solanaceae) was tested against the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), for its toxic and antifeedant activity. The dried and powdered plant was extracted with 150 mL of absolute ethanol (99%, Merck) using a rotary evaporator extractor at 45 °C. Experiments were designed to measure the nutritional indices, such as relative growth rate (RGR), relative consumption rate (RCR), efficiency of conversion of ingested food (ECI), and feeding deterrence index (FDI). Treatments were evaluated by flour disk bioassay in the dark at 27 ± 1 °C and 60 ± 5% RH. Aliquots of 10 µL of acetone (control) or acetone extract (947-3007 mg L-1) were spread evenly on the flour disks. The solvent was allowed to evaporate, and then 10 adult insects were introduced into each treatment. After 72 h, nutritional indices were calculated. On the basis of the designed experiments, the calculated lethal concentrations of LC50 and LC90 of D. stramonium were 3936 and 15373 mg L-1, respectively. Results indicated that nutritional indices varied significantly as plant extract concentrations increased. As the concentration of D. stramonium increased, RGR, RCR, and ECI indices were reduced, and the most significant effect was observed at 3007 mg L-1. On the other hand, the FDI index increased with increasing extract doses and, as a result, insect food consumption was reduced. The results of data analysis showed that there is a significant difference between the plant and different concentrations in the feeding deterrence index of T. castaneum.

The oligophagous pest Plutella xylostella (L.) is a major crucifer pest in Tehran Province, Iran. Hexaflumuron is an insect growth regulator insecticide with good effects on immature insect stages. The objective of this study was to investigate the effects of two sublethal concentrations (LC10 and LC25) of hexaflumuron on some biological parameters of P. xylostella larvae, such as birth rate (b), death rate (d), finite rate of increase (λ), generation time (T), sex ratio, pupation rate, and adult emergence. Results showed that hexaflumuron decreased the total number of eggs and oviposition and post-oviposition periods, pupation, and adult emergence in the treated generation, b, and λ. Hexaflumuron also increased T, d, and the pre-oviposition period. However, sex ratio, percentage of pupation, and adult emergence in the offspring generation were not affected by hexaflumuron. Overall, these results indicated that sublethal concentrations of hexaflumuron can affect the biological parameters of P. xylostella. Plutella xylostella (L.), una plaga oligofaga, es una importante plaga de crucíferas en la provincia de Teherán, Irán. Hexaflumuron, un insecticida regulador de crecimiento de insectos, tiene buenos efectos sobre estados inmaduros de insectos. El objetivo de este estudio es investigar los efectos de dos concentraciones subletales (LC10 y LC25) de hexaflumuron sobre algunos parámetros de larvas de P. xylostella tales como tasa de nacimiento (b) y tasa de mortalidad (d), tasa finita de aumento (λ), tiempo de generación (T), proporción de sexos, tasa de pupación, emergencia de adultos, y algunos otros parámetros. Los resultados mostraron que hexaflumuron redujo el número total de huevos y ovipostura y períodos de post-ovipostura, pupación, y emergencia de adultos en la generación tratada, b y λ. Hexaflumuron además aumentó T, d y el período pre-ovipostura. Sin embargo, la proporción de sexos, porcentaje de pupación, y emergencia de adultos en la generación producto no fueron afectados por hexaflumuron. En conclusion, estos resultados indicaron que las concentraciones subletales de hexaflumuron pueden afectar los parámetros biológicos de P. xylostella.

The oligophagous pest Plutella xylostella (L.) is a major crucifer pest in Tehran Province, Iran. Hexaflumuron is an insect growth regulator insecticide with good effects on immature insect stages. The objective of this study was to investigate the effects of two sublethal concentrations (LC10 and LC25) of hexaflumuron on some biological parameters of P. xylostella larvae, such as birth rate (b), death rate (d), finite rate of increase (λ), generation time (T), sex ratio, pupation rate, and adult emergence. Results showed that hexaflumuron decreased the total number of eggs and oviposition and post-oviposition periods, pupation, and adult emergence in the treated generation, b, and λ. Hexaflumuron also increased T, d, and the pre-oviposition period. However, sex ratio, percentage of pupation, and adult emergence in the offspring generation were not affected by hexaflumuron. Overall, these results indicated that sublethal concentrations of hexaflumuron can affect the biological parameters of P. xylostella.

The saxaul locust, Dericorys albidula Serville (Orthoptera: Dericorythidae) is a major pest of saxaul plants in Qom province of Iran. During 2005-2006, different nymphal instars of bands of D. albidula were treated by aerial spraying of Metarhizium anisopliae var. acridum (Green Muscle®). The gasoline formulation of M. anisopliae var. acridum isolate IMI 330189 was applied in different conidial concentrations (10(6), 10(7), 10(8), 10(9), 10(10) and 10(13) spores mL-1) that were prepared in sterile distilled gasoline. Results showed that various concentrations significantly affected the 2nd, 3rd, 4th and 5th nymphal instars of D. albidula compared to control. In addition, there were no differences in the effects of the different concentrations in 2005, but the differences were significant in 2006. Concentration 10(10) killed 100% of tested insects 15 d after treatment. Comparing the results of the two years showed that the susceptibility of nymphs in the second year (2006) was higher than in the first year (2005). In conclusion, the results of this study indicated that the fungal insecticide M. anisopliae var. acridum, diluted in gasoline, was efficacious with the nymphal instars of locust D. albidula in 2005 and 2006. La langosta del saxaul, Dericorys albidula Serville (Orthoptera: Dericorythidae), es la principal plaga de plantas de saxaul de las provincias Qom, Irán. Durante 2005-2006, diferentes instars ninfales de D. albidula se asperjaron con Metarhizium anisopliae var. acridum (Green Muscle®). La formulación de gasolina de M. anisopliae var. acridum aislamiento IMI 330189 se aplicó en diferentes concentraciones conidiales (10(6), 10(7), 10(8), 10(9), 10(10) and 10(13) esporas mL-1) preparadas en gasolina destilada estéril. Los resultados demostraron que varias concentraciones afectaron significativamente los nstars ninfales de D. albidula comparado con el control. Además el efecto de concentraciones no fue diferente en 2005 pero sí significativamente en 2006. La concentration 10(10) mató 100% de insectos 15 d después del tratamiento. La comparación de los resultados de estos anos mostró que la susceptibilidad de ninfas en el segundo ano (2006) fue mayor que en el primer ano (2005). En conclusión, los resultados de este estudio indicaron que el insecticida fúngico M. anisopliae var. acridum diluido en gasolina tuvo buena eficacia sobre los instars ninfales de langosta D. albidula en los anos 2005 y 2006.

The diamondback moth, Plutella xylostella (Lepidoptera: Yponomeutidae), is a serious threat to Brassica vegetables in Iran, including Tehran province. The ovicidal effects of different classes of insecticides on P. xylostella were investigated, using three fixed doses (based on commercial formulations). At the lowest concentration (500 mg L-1), the mortality effect of hexaflumuron and pyridalyl was higher than the other insecticides examined. Fipronil, hexaflumuron and spinosad and pyridalyl, however, showed high toxic effects at the median dose (1000 mg L-1). On the other hand, at high concentration (2000 mg L-1), all insecticides except lufenuron and indoxacarb (EC formulation) caused more than 85% mortality. Overall, these findings indicate that hexaflumuron, spinosad and fipronil, with low active ingredients and high mortality, could be the best choices for controlling the P. xylostella in the egg stage. La polilla del repollo, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae), es un serio riesgo para especies Brassica en Irán, incluyendo la provincia de Teherán. Se investigó el efecto ovicida de algunos insecticidas pertenecientes a diferentes clases de P. xylostella usando tres dosis (basadas en formulaciones comerciales). A la menor concentración (500 mg L-1) el efecto de mortalidad de hexaflumuron y piridalil fue mayor que las otras dosis examinadas. Fipronil, hexaflumuron spinosad y piridalil, sin embargo, mostraron fuertes efectos tóxicos a la dosis media (1000 mg L-1). Por otra parte, a alta concentración (2000 mg L-1) todos los insecticidas excepto lufenuron e indoxacarb (formulación EC) causaron más de 85% mortalidad. Finalmente, estos hallazgos indican que hexaflumuron, spinosad y fipronil con baja concentración de ingredientes activos y alta mortalidad pueden ser la mejor elección para controlar P. xylostella en el estado de huevo.

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. Materiales vegetales con propiedades insecticidas han sido usados tradicionalmente por generaciones en algunas partes del mundo. En este estudio se estudió la toxicidad fumigante de algunos aceites esenciales extraídos desde Rosmarinus officinalis L., Mentha pulegium L., Zataria multiflora y Citrus sinensis (L.) Osbeck var. hamlin sobre adultos de plagas de productos almacenados, incluyendo Tribolium castaneum, Sitophilus granarius, Callosobruchus maculatus y Plodia interpunctella. Para los bioensayos se usaron aceites esenciales puros en frascos de vidrio. Los valores de LC50 de C. sinensis var. hamlin contra T. castaneum, S. granarius y C. maculatus fueron 391.28, 367.75 y 223.48 después de 24 h y 362.40, 20.45 y 207.17 µL L-1 aire después de 48 h, respectivamente. Además, los valores de LC50 de la prueba fumigante del aceite esencial de C. sinensis y M. pulegium contra S. granarius después de 24 h fueron 0,038 y 367,75 µL L-1 aire y fueron 0,025 y 320,45 después de 48 h, respectivamente. Por otra parte, los valores de LC50 de R. officinalis y Z. multiflora en polillas de P. interpunctella después de 24 h fueron 0,93 y 1,75 µL L-1. Los resultados mostraron que entre los aceites esenciales, C. sinensis var. hamlin tuvo una buena toxicidad fumigante sobre T. castaneum, S. granarius, C. maculatus. Además, el aceite esencial de M. pulegium fue más fuerte que C. sinensis var. hamlin sobre S. granarius. Los resultados además indicaron que Z. multiflora and R. officinalis tuvieron toxicidad fumigante sobre adultos de P. interpunctella. En conclusión, los resultados indicaron que estos aceites esenciales tienen buena toxicidad fumigante sobre plagas de productos almacenados.

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.