F. Tabe bordbar; S. Moharramipour
Abstract
The Diamond back moth Plutella xylostella L. is one of the major pests of plants in Brassicaceae that has become resistant to many insecticides. In recent years, plant secondary metabolites play an important role in controlling pests because of their insecticidal and antifeedant properties. A laboratory ...
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The Diamond back moth Plutella xylostella L. is one of the major pests of plants in Brassicaceae that has become resistant to many insecticides. In recent years, plant secondary metabolites play an important role in controlling pests because of their insecticidal and antifeedant properties. A laboratory experiment was conducted to investigate the effect of methanolic extracts of Matteuccia struthiopteris (L.) on diamondback moth third instar larvae. Findings showed significant increase in mortality as concentrations increased, so that, concentrations to cause 25% (LC25) and 50% (LC50) mortality in population were 12.01% and 28.58%, respectively. In this research, the effect of sublethal concentration of methanolic extract was studied on demography parameters such as life table, reproductive and population of P. xylostella. The obtained results showed that different concentration had a significant effect on the duration of different life stage, fecundity and adult longevity. Data analysis demonstrated that increased concentration decreased the net reproductive rate (R0), intrinsic rate of natural increase (rm), finite rate of increase (λ) but increased mean generation time (T) and doubling time (DT) significantly. These findings indicate that M. struthiopteris has the potential to be used as a reliable method in integrated management of this pest.
B.Z. Sahaf; S. Moharramipour
Abstract
In this research, the effect of ecdysteoidal extract from Spinacia oleracea L. (Chenopodiceae), a plant producing phytoecdysteroids, was evaluated on the life table and population growth parameters of Ephestia kuehniella (Lepidoptera: Pyralidae). Ecdysteroidal extract of the plant leaves, containing ...
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In this research, the effect of ecdysteoidal extract from Spinacia oleracea L. (Chenopodiceae), a plant producing phytoecdysteroids, was evaluated on the life table and population growth parameters of Ephestia kuehniella (Lepidoptera: Pyralidae). Ecdysteroidal extract of the plant leaves, containing 20 hydroxyecdysone, was incorporated into the food given to the insect. Newly hatched larvae (100 replications) were reared individually in test glasses. Data analysis demonstrated that the intrinsic rate of increase (rm), mean generation time (T), finite rate of increase (l) and net reproduction rate (R0) decreased significantly as concentration of the extract increased. In addition, doubling time (DT) increased significantly as concentration of the extract increased. Life expectancy of the insect (ex)alsoincreased. Total development duration in treated insects was always significantly longer than that in the control group. The control insects had four instar larvae, but it was six for the treated larvae. Data demonstrated that E. kuehniella was partially resistant to ingested exogenous ecdysteroids. Nevertheless, exogenous ecdysteroids were able to disrupt larval development and reduced the fertility. Therefore, this extract may be a potential protectant as botanical alternative agent, and can be used as a biopesticide to control E. kuehniella population.
M. Negahban; S. Moharramipour; M. Zandi; S.A. Hashemi
Abstract
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 ...
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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.
M. Negahban; S. Moharramipour; M. Zandi; S.A. Hashemi
Abstract
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 ...
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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.
B.Z. Sahaf; S. Moharramipour
Volume 24, Issue 4 , February 2009, , Pages 385-395
Abstract
The essential oils extracted from Carum copticum C. B. Clarkeand Vitex pseudo-negundo (Hausskn.) Hand.-Mzt. using hydro distillation was tested against the stored product insect, Tribolium castaneum (Herbst),for antifeedant activity. Several experiments were designed to measure the nutritional indices ...
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The essential oils extracted from Carum copticum C. B. Clarkeand Vitex pseudo-negundo (Hausskn.) Hand.-Mzt. using hydro distillation was tested against the stored product insect, Tribolium castaneum (Herbst),for antifeedant activity. Several 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 the method of flour disc bioassay in the dark, at 27±1°C and 60±5 % R. H. Aliquots of 10 µl of acetone (controls) or an acetone solutions of essential oils (100-1500 ppm) were spread evenly on the flour discs. The solvent was allowed to evaporate and then 10 adult insects were introduced into each treatment. After 72 h, nutritional indices were calculated. Results indicated that nutritional indices were significantly varied as essential oil concentrations increased. In this study, C. copticum decreased RGR, RCR and ECI significantly higher than that of V. pseudo-negundo essential oil. Both of plant essential oils, with the same activity, increased FDI as the oil concentration was increased, showing high feeding deterrence activity against T. castaneum. Generally, antifeedant activity of C. copticum was more effective than V. pseudo-negund.
J. Nazemi Rafih; S. Moharramipour
Abstract
Red flour beetle Tribolium castaneum isa major pest of stored products especially cereal flour depreciating the quantity and quality of the food economically. The application of repellents could be considered as a new control method in storage. In this study repellent activity of extracts from leaf, ...
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Red flour beetle Tribolium castaneum isa major pest of stored products especially cereal flour depreciating the quantity and quality of the food economically. The application of repellents could be considered as a new control method in storage. In this study repellent activity of extracts from leaf, red and white flowers of Nerium oleander, Lavandula officinalis leaves and Ferula assafoetida gum was assayed on T. castaneum. Experiments were conducted in dark condition at 27±1ºC and 70-80% RH. To determine percentage repellency (PR), filter paper disks were impregnated with different concentrations of plant extracts. Each filter paper was divided into two equal parts. Then, each half-disk was separately added by extract dilutions (1.99, 3.98, 11.94, 19.90 and 27.78 μl/cm2) or acetone as control. Each treated half-disk was then attached lengthwise edge-to-edge, to a control half-disk with adhesive tape and placed in a petri dish (8cm diam.). Twenty adult insects were released in the middle of each filter paper, and the insects that settled on each half, were counted after 1 h and then at hourly intervals for 5h. The results showed that the repellency of Ferula gum was significantly higher than that of remaining extracts. The highest PR (98.75%) was observed in the Ferula gum in the concentration of 27.78 μl/cm2. While, the lowest PR (5.5%) was shown in the Lavandula leaf extract in 1.99 μl/cm2. Repellency increased with concentration in all cases, the repellent effect did not decreased with time over the 5-h experimental period.
B.Z. Sahaf; S. Moharramipour
Abstract
Recently, there has been a growing interest in research concerning the possible use of plant extracts as alternatives to synthetic insecticides. Essential oils are among the best-known substances tested against insects. These compounds may act as fumigants, contact insecticides, repellents, antifeedants ...
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Recently, there has been a growing interest in research concerning the possible use of plant extracts as alternatives to synthetic insecticides. Essential oils are among the best-known substances tested against insects. These compounds may act as fumigants, contact insecticides, repellents, antifeedants and may affect growth and development of the insect. The objective of the present study was to test the possible properties of, medicinal plants, Carum copticum C. B. Clarke (Apiaceae) and Vitex pseudo-negundo (Haussk) Hand. I. MZT. (Verbenaceae) essential oil vapors against Callosobruchus maculatus (F.) to elucidate their deterrency on oviposition. The experiment was conducted with six concentrations (0.02-0.5 ml oil per one gram seed) at 27 ± 1°C, 60 ± 5 % R.H. and in dark condition. The essential oils were obtained from dry seeds of C. copticum and leaves of V. pseudo-negundo subjected to hydrodistillation using a modified clevenger-type apparatus. In each vial, two pairs of adult insects and 10 g chikling vetch were used. Oviposition deterrence of C. copticum was significantly higher than V. pseudo-negundo. At the highest concentration (0.5 ml per one gram seed) oviposition deterrence was reached to 100% and 76.33% by C. copticum and V. pseudo-negundo, respectively. Our results showed that these essential oils exhibited strong oviposition deterreny on C. maculatus at sublethal doses.
