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1.
BACKGROUND: The ethyl formate/carbon dioxide (CO2) formulation Vapormate? is a rapid‐acting fumigant being developed for the control of stored‐grain insects. The effects have been investigated of concentration, exposure times of 1, 3, 24 and 72 h and two grain temperatures, 15 and 25 °C, on its efficacy against mixed‐stage cultures of Sitophilus oryzae (L.) Tribolium castaneum (Herbst) and strongly phosphine‐resistant Rhyzopertha dominica (F.) strain QRD569. RESULTS: High mortalities (≥92%) of mixed‐stage cultures of all three species were obtained when grain was fumigated with the formulation (193 g m?3 ethyl formate) for 1 h. Complete control of R. dominica QRD569 and T. castaneum was achieved with 63 and 76 g m?3 ethyl formate respectively, with exposure for 24 h, whereas mean mortality of S. oryzae was 86% under the same conditions. Mortalities of S. oryzae juvenile stages were significantly lower than adults under the conditions tested, which was due to pronounced tolerance of mid‐stage pupae to the fumigant. Reducing grain temperature from 25 to 15 °C had no effect on insect mortality. CONCLUSION: Ethyl formate/CO2 formulation is highly effective against stored‐grain insects over a range of concentrations and exposure times. Efficacious fumigations were conducted in as little as 1 h, and a strongly phosphine‐resistant R. dominica strain was readily controlled with the fumigant. Copyright © 2009 CSIRO, Australia. Published by John Wiley & Sons, Ltd  相似文献   

2.
BACKGROUND: Methyl bromide is being phased out for use on stored commodities, as it is listed as an ozone‐depleting substance, and phosphine is the fumigant widely used on grains. However, phosphine resistance occurs worldwide, and phosphine fumigation requires a long exposure period and temperatures of > 15 °C. There is an urgent requirement for the development of a fumigant that kills insects quickly and for phosphine resistance management. This paper reports on a new fumigant formulation of 95% ethyl formate plus 5% methyl isothiocyanate as an alternative fumigant for stored grains. RESULTS: The formulation is stable for at least 4 months of storage at 45 °C. A laboratory bioassay with the formulation showed that it controlled all stages of Sitophilus oryzae (L.), Sitophilus granarius (L.), Tribolium castaneum (Herbst), Rhyzopertha dominica (F.), Trogoderma variabile Ballion and Callosobruchus maculatus (Fabricius) in infested wheat, barley, oats and peas at 80 mg L?1 for 5 days, and in canola at both 40 mg L?1 for 5 days and 80 mg L?1 for 2 days at 25 ± 2 °C. After an 8–14 day holding period, residues of ethyl formate and methyl isothiocyanate in wheat, barley, peas and canola were below the experimental permit levels of 1.0 and 0.1 mg kg?1. However, fumigated oats needed an 18 day holding period. CONCLUSIONS: The findings suggest that the ethyl formate plus methyl isothiocyanate formulation has potential as a fumigant for the control of stored‐grain insect pests in various commodities. Copyright © 2011 Society of Chemical Industry  相似文献   

3.
Organophosphorothioates and synergised synthetic pyrethroids were used in duplicate field trials carried out on bulk wheat in commercial silos in Queensland and New South Wales. Laboratory bioassays using malathion-resistant strains of insects were carried out on samples of treated grain at intervals over 9 months. These established that all treatments were generally effective. Deltamethrin (2 mg kg?1)+ piperonyl butoxide (8 mg kg?1), fenitrothion (12 mg kg?1)+ fenvalerate (1 mg kg?1)+ piperonyl butoxide (8 mg kg?1), fenitrothion (12 mg kg?1)+ phenothrin (2 mg kg?1)+ piperonyl butoxide (8 mg kg?1) and pirimiphos-methyl (4 mg kg?1)+ permethrin (1 mg kg?1)+ piperonyl butoxide (8 mg kg?1) controlled common field strains of Sitophilus oryzae (L.) and Rhyzopertha dominica (F.). Against a highly resistant strain of S. oryzae, deltamethrin (2 mg kg?1)+ piperonyl butoxide (8 mg kg?1) was superior to the remaining treatments. All treatment combinations completely prevented progeny production in Tribolium castaneum (Herbst), T. confusum Jacquelin du Val and in Ephestia cautella (Walker). Residues of deltamethrin, fenvalerate, permethrin and phenothrin were determined and shown to be highly persistent on stored wheat. During milling, residues accumulated in the bran fractions and were reduced in white flour. They were not significantly reduced during baking.  相似文献   

4.
Consumption of pea (Pisum sativum L.) protein-treated wheat flour by the red flour beetleTribolium castaneum (Herbst.), the rice weevilSitophilus oryzae (L.) and the lesser grain borerRhyzopertha dominica (F.), was significantly reduced compared with wheat flour alone. Consumption was affected when the insects were exposed for 3 days to flour disks containing protein-rich fraction of the ‘Bonneville’ pea variety. Antifeedants present in the pea protein fraction are apparently responsible for the reduced feeding response in these species. http://www.phytoparasitica.org posting May 6, 2004.  相似文献   

5.
Duplicate field trials were carried out on bulk wheat in commercial silos in Queensland and New South Wales. Laboratory bioassays on samples of treated grain at intervals over 9 months, using malathion-resistant strains of insects, established that treatments were generally effective. Fenitrothion (12 mg kg?1)+ (1R)-phenothrin (2 mg kg?1) was more effective than pirimiphos-methyl (6 mg kg?1) + carbaryl (10 mg kg?1) against Sitophilus oryzae (L.) and Ephestia cautella (Walker); the order of effectiveness was reversed for S. granarius (L.). Against Rhyzopertha dominica (F.), Tribolium castaneum (Herbst), T. confusum Jackquelin du Val and Oryzaephilus surinamensis (L.), both treatments effectively prevented the production of progeny. The order of persistence was pirimiphos-methyl> (1R)-phenothrin>carbaryl or fenitrothion. During processing from wheat to white bread, residues were reduced by 98% for carbaryl, >44% for (1R)-phenothrin, 98% for fenitrothion and 85% for pirimiphosmethyl.  相似文献   

6.
BACKROUND: Fipronil is an insecticidal pyrazole that is commonly used as an insecticide in field crops, urban pesticide and veterinary medicine, but there are no reports of its evaluation against stored‐product insects. Three series of laboratory bioassays were conducted to assess fipronil as a potential grain protectant against adults of Sitophilus oryzae (L.), Tribolium confusum Jacquelin du Val, Rhyzopertha dominica (F.) and Prostephanus truncatus (Horn). Factors such as dose (0.01, 0.1, 1 and 10 mg fipronil kg?1 grain), exposure interval (24 h, 48 h, 7 days and 14 days), temperature (20, 25 and 30 °C), relative humidity (RH; 55 and 65%) and commodity (wheat, maize, barley and paddy rice) were evaluated with regard to their impact on the insecticidal activity of fipronil. Progeny production was assessed after 64 days of exposure. RESULTS: At doses of < 1 mg fipronil kg?1 grain, efficacy of fipronil was enhanced by an increase in temperature from 20 to 25 °C against S. oryzae or R. dominica for exposures of > 48 h and against T. confusum or P. truncatus for exposures of > 24 h. A further increase in temperature from 25 to 30 °C, although it enhanced efficacy at doses of < 1 mg fipronil kg?1 grain against S. oryzae at all exposure intervals and against T. confusum after 7 days of exposure, it was negatively associated with efficacy against R. dominica or P. truncatus for exposures of > 24 h. By contrast, increase in RH did not have a significant impact on efficacy of fipronil. Although the performance of fipronil among the tested commodities was species dependent, this substance appeared to be less effective in paddy rice than in barley, maize and wheat. Regardless of the treated commodity, progeny production of all the tested species was almost suppressed with doses higher than 0.1 mg fipronil kg?1 grain. CONCLUSIONS: Fipronil appeared to be a very effective alternative to the existing substances in stored‐grain protection at doses equal to or higher than 1 mg fipronil kg?1 grain, and thus these doses require further evaluation in terms of safety for the consumer and residues on stored products. Copyright © 2010 Society of Chemical Industry  相似文献   

7.
The commercially available trap WB Probe II Trap have been used in laboratory to monitor insects activity in grains at 24±1°C and 70±5% r.h.. The major coleopteran pests of cereals in Italy,Oryzaephilus surinamensis (L.),Rhyzopertha dominica (F.),Sitophilus oryzae (L.) andTribolium castaneum (Herbst), were added to the grain at about 0.9 insect per kg. Two tests were prepared: in the testA insect activity was observed in spring wheatTriticum aestivum, L.; in the testB were compared in oat grainAvena sativa L., spring wheatTriticum aestivum L. and maize grainZea mays L. Significant differences in the numbers of insects collected by the traps were observed, both when compared across traps and cereal types. In all cereals considered traps trapped moreS. oryzae thanT. castaneum andO. surinamenis; the species less trapped wereR. dominica.  相似文献   

8.
A study was conducted to determine the extent of resistance to malathion in field populations of insects collected from nine granaries located in different regions of Israel. The results showed that the maximum resistance factor calcuated from the LCso s of the different insect species tested was:Tribolium castaneum (Herbst), x 538.0;Oryzaephilus surinamensis (L.), x 8.0;Sitophilus oryzae (L.), x 1.2; andRhyzopertha dominica (F.), x 9.0. There were significant differences between the resistance level among strains collected from different locations in Israel. By using triphenyl phosphate (TPP), an inhibitor of carboxyesterase, it was shown that, in the case ofT. castaneum andR. dominica, the resistance is a malathion-specific type and that in the case ofO. surinamensis it is partially non-specific to malathion. The significance of these findings in selecting new insecticides to replace malathion as a grain protectant was considered.  相似文献   

9.
BACKGROUND: Gaseous ozone (O3) has potential for control of insects in stored grain. Previous studies have focused on freely exposed insects. Immatures of internal pests (e.g. Sitophilus spp. and most stages of Rhyzopertha dominica F.) are protected within kernels and probably require higher doses and/or longer treatment times for full control. A laboratory study determined the doses of ozone necessary for full control of freely exposed and internal stages of eleven stored‐product pest species. Test insects were three species of Sitophilus, R. dominica, Tribolium confusum Jacquelin du Val, T. castaneum Herbst, Plodia interpunctella Hübner, Sitotroga cerealella Olivier, Oryzaephilus surinamensis L., Ephestia kuehniella Zeller and Stegobium paniceum L. Insects were exposed to continuous flows of ozone in doses of 10–135 ppm and exposure times of 5–8 days. Dose‐mortality bioassays were conducted on three species of Sitophilus and P. interpunctella. RESULTS: Freely exposed stages (with a few exceptions) were controlled with 35 ppm of ozone for 6 days. Full mortality of internal stages within kernels required exposure to 135 ppm for 8 days. CONCLUSION: This study confirms that higher doses and/or longer treatment times are necessary for control of internal stages of stored‐product pests. Copyright © 2012 Society of Chemical Industry  相似文献   

10.
BACKGROUND: The composition and bioactivity of essential oils from Tagetes terniflora Kunth, Cymbopogon citratus Stapf. and Elyonurus muticus (Spreng) Kuntz were evaluated against stored‐grain pests. RESULTS: Fumigant and contact toxicities were observed with T. terniflora on adults of both pests. In contact toxicity, this oil was less toxic to Tribolium castaneum (Herbst). Essential oils from C. citratus and E. muticus showed contact toxicity on S. oryzae. All essential oils produced: (a) repellency on larvae and adults of T. castaneum and adults of Sitophilus oryzae (L.); (b) post‐ingestive toxicity on T. castaneum larvae and S. oryzae adults and alteration of nutritional index on T. castaneum and S. oryzae adults. Cymbopogon citratus reduced the relative growth rate and the efficiency of conversion of ingested food in T. castaneum larvae. Tagetes terniflora produced a feeding stimulant effect in T. castaneum adults. In addition, they had a feeding deterrent action against S. oryzae adults. The composition of essential oils from C. citratus and E. muticus varied only in one component. CONCLUSION: These results showed that the essential oils from T. terniflora, C. citratus and E. muticus should be studied further for their use in integrated pest management programmes for T. castaneum and S. oryzae control. Copyright © 2011 Society of Chemical Industry  相似文献   

11.
Duplicate experiments were carried out on bulk sorghum stored in South Queensland and in Central Queensland. Bioassays of treated grain, conducted during 6 months' storage, established that fenitrothion (12 mg kg?1)+ bioresmethrin (1 mg kg?1), and pirimiphos-methyl (4 mg kg?1)+ carbaryl (8 mg kg?1), controlled typical malathionresistant strains of Sitophilus oryzae (L.), Rhyzopertha dominica (F.), Tribolium castaneum (Herbst), and Ephestia cautella (Walker). Chlorpyrifos-methyl (10 mg kg?1)+ pyrethrins (1.5 mg kg?1)+ piperonyl butoxide (12 mg kg?1), and fenitrothion (12 mg kg?1)+ (1R)-phenothrin (1 mg kg?1), also controlled the strains of S. oryzae, T. castaneum and E. cautella, but were only partly effective against R. dominica. Methacrifos (15 mg kg?1) controlled all the tested species except E. cautella. Chemical assays established that the residues and rates of breakdown of these grain protectants on sorghum conformed to the general pattern for other cereal grains; residues from the above treatments were below the individual Maximum Residue Limits recommended by the Codex Alimentarius Commission.  相似文献   

12.
Bioassays were conducted in stored grains to evaluate the combined use of the entomopathogenic fungus Beauveria bassiana, diatomaceous earth (DE) and fenitrothion against adults of Rhyzopertha dominica and Tribolium castaneum. The insecticide agents were applied to wheat as follows: the fungus at 1 × 108 conidia/kg of wheat, DE at 3 g/kg of wheat and fenitrothion at a rate of 0.15 ml/kg of wheat (25% of field dose rate). Surviving insects and progeny production were monitored at thirty-day intervals until four months. For both insect species, significantly less progeny was produced on wheat treated with fenitrothion and DE + B. bassiana formulations in comparison with controls. The effect of insecticides on the grain damage, germination power of wheat and bulk density was also evaluated. After four months, B. bassiana mixed with DE reduced the damaged insect grains by 50% in comparison with both fenitrothion and control treatments. Trials using DE caused a reduction in bulk density while there were no significant differences for germination testing between treatments.  相似文献   

13.
BACKGROUND: Environmental impacts and resistance to insecticides pose serious challenges to stored‐product insect and other types of pest control. Insect‐resistant transgenic grain is a potential alternative to fumigants, but candidate control proteins are needed, especially for coleopterans. Therefore, we evaluated the efficacy of a coleopteran‐active toxin, Bacillus thuringiensis Cry3Aa, with or without protease inhibitors, in laboratory feeding assays against coleopteran storage pests. RESULTS: In a comparison of the toxicity of Cry3Aa protoxin towards three species of coleopteran storage pests, Tenebrio molitor L. was found to be most sensitive, Tribolium castaneum (Herbst.) was most refractory and Rhyzopertha dominica F. displayed an intermediate response. For R. dominica, Cry3Aa combined with 3500 mg potato carboxypeptidase inhibitor or 5000 mg aprotinin kg?1 diet resulted in both delayed development and increased mortality. Potato carboxypeptidase inhibitor and bovine aprotinin reduced the LC50 of Cry3Aa for R. dominica two‐ and threefold respectively. Cry3Aa treatment resulted in fewer progeny from R. dominica, and progeny was further reduced when the protoxin was combined with potato carboxypeptidase inhibitor. CONCLUSIONS: These data support the hypothesis that a combination of Cry3Aa protoxin and protease inhibitors, particularly a potato carboxypeptidase inhibitor, may have applications in control strategies for preventing damage to stored products and grains by coleopteran pests. Published 2011 by John Wiley & Sons, Ltd.  相似文献   

14.
The FAO global survey of pesticide sensitivity of stored grain pests in 1972–73 showed an overall incidence of phosphine resistance of 9.7% in insect strains from 82 countries, especially in Tribolium spp. and Rhyzopertha dominica. The levels of resistance increased under laboratory selection. Generally, eggs and pupae were found to be more tolerant, and fumigation doses have to be designed with these stages in mind. With increasing worldwide use of phosphine, resistance has become more frequent and occurs at a higher level and in other species (Cryptolestes ferrugineus, Oryzaephilus surinamensis). Studies of fumigation under different conditions in Bangladesh showed that common procedures, without use of sheets, led to chronic underdosing, creating ideal conditions for the selection of resistant strains. Such strains are very likely to be introduced into the EPPO region and established there. While inspection and control procedures in ports could limit this risk, these are costly and impractical. The problem is best tackled at source, by supporting projects aimed at improving the conditions under which grain is stored and fumigated in developing countries.  相似文献   

15.
Field trials with various pesticide combinations were carried out on bulk wheat in commercial silos in Queensland, South Australia and Western Australia. Laboratory bioassays on samples of treated grain at intervals over 8 months using malathion-susceptible and malathion-resistant strains established the following orders of efficacy: against Sitophilus oryzae (L.), chlorpyrifos-methyl 10 mg kg?1 + bioresmethrin 1 mg kg?1 = methacrifos 15 mg kg?1 in aerated storage > pirimiphos-methyl 4 or 6 mg kg?1 + bioresmethrin 1 mg kg?1 = bioresmethrin 4 mg kg?1 + piperonyl butoxide 16 mg kg?1; against Rhyzopertha dominica (F.), bioresmethrin 4 mg kg?1 + piperonyl butoxide 16 mg kg?1 > methacrifos 15 mg kg?1 > chlorpyrifos-methyl 10 mg kg?1 + bioresmethrin 1 mg kg?1 = pirimiphos-methyl 4 or 6 mg kg?1 + bioresmethrin 1 mg kg?1. All treatments completely prevented production of progeny in Sitophilus granarius (L.), Tribolium castaneum (Herbst), T. confusum Jackquelin du Val and Oryzaephilus surinamensis (L.). The biological efficacy of methacrifos was greater and the rate of degradation lower in aerated than in non-aerated storage. Residue levels of all compounds were determined chemically and were below proposed international residue levels to be considered by the Codex Alimentarius Commission.  相似文献   

16.
BACKGROUND: Insect growth regulators are promising alternatives to traditional pesticides in stored grain. The efficacy of the juvenile hormone analogue methoprene was evaluated as a layer treatment in a laboratory experiment for control of Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) in wheat, rice and maize. RESULTS: Adults of R. dominica were placed in vials containing 33, 26 and 29 g (to a depth of 6.5 cm) of wheat, rice and maize, respectively, that was entirely or partially treated with 1, 5 or 10 mg kg?1 methoprene. In wheat and rice, the layer treatments were not as effective as the whole‐grain treatment, but there was decreased progeny production as the application rate increased. However, on maize the partial treatments were as effective as the whole‐grain treatment at 5 and 10 mg kg?1. CONCLUSIONS: The results suggest that partial layer treatments with methoprene can be used to control R. dominica on maize but may not be effective for control of this species on wheat and rice. Copyright © 2011 Society of Chemical Industry  相似文献   

17.
Ethyl formate is being evaluated as a fumigant for stored grain as it is a potential alternative to the ozone-depleting fumigant methyl bromide and to phosphine, which is under pressure owing to the development of strong resistance in stored grain insects. However, use of ethyl formate faces significant challenges, such as poor penetration through grain, significant losses to grain sorption, high concentrations of fumigant required to control insects, and flammability risks, which have limited its further development. In this study it was found that the combination of carbon dioxide (5-20%) with ethyl formate significantly enhanced efficacy of the fumigant against external living stages of the rice weevil, Sitophilus oryzae (L.), the lesser grain borer, Rhyzopertha dominica F., and the flour beetle, Tribolium castaneum (Herbst). Dynamic application of ethyl formate and carbon dioxide mixture (100 mg litre-1 ethyl formate, 20% CO2) pumped through a model silo containing wheat (50 kg) for one gas exchange was also investigated. A flow rate of 6 litres min-1 gave a relatively even distribution of fumigant throughout the grain column and similar mortality levels among cultures of S. oryzae and T. castaneum placed at three positions, the top, middle and bottom of the column. Mortality of 99.8% of mixed stage cultures of T. castaneum and 95.1% of S. oryzae was achieved in 3 h exposures to 111 and 185 mg ethyl formate h litre-1 respectively applied by the dynamic method. It is concluded that the combination of carbon dioxide with ethyl formate and dynamic application enhances distribution and efficacy of the fumigant against stored grain insects.  相似文献   

18.
T. Hoppe  M. Suchy 《EPPO Bulletin》1975,5(2):193-196
Two insect growth regulators of the juvenile hormone type, namely 6,7-epoxy-3-ethyl-(p-ethylphenoxy)-7-methylnonane, cis/trans mixture (compound A) and 6,7-epoxy-3,7-dimethyl-1-[3,4-(methylendioxy)-phenoxy]-2-nonene (compound B) have been tested for their persistence when treated on stored grain. The interim results of this trial showed inhibition of adult emergence of Ephestia kühniella Zell., Plodia interpunctella Hübn., Tribolium castaneum Herbst and Rhyzopertha dominica F. even 8 months after treatment. The gas-chromatography residue determination of compound A showed a reduction of 27 % of the original concentration within 8 months. No effect of compound A on the endosperm of the grain or taste of flour and bread could be found in the Bakery School in Lucerne.  相似文献   

19.
BACKGROUND: Ethyl formate formulations are being considered to replace methyl bromide for fast grain disinfestation. Grain adsorbs ethyl formate rapidly, which can result in inadequate fumigation concentrations and unacceptable grain residues. A model of ethyl formate sorption kinetics will enable fumigation approaches to be determined that meet disinfestation and food safety requirements. RESULTS: This paper identifies all mass transport processes involved in ethyl formate sorption by wheat from published and experimental evidence. The model accounts for reaction losses of ethyl formate in air and grain using first‐order kinetics, transport in the gas and solid phases with linear mass transfer coefficients and uses a linear partition relationship representation of sorption equilibrium. Batch experimental data were measured to determine model coefficients. Novel gaseous breakdown data for ethyl formate in air were measured, and first‐order kinetics was demonstrated, although the specific reactions involved were not identified. CONCLUSION: The model predicts air and grain fumigant concentrations relevant for grain disinfestation and food residue contamination successfully. The form of the model should be applicable to all fumigant–grain systems, as it accounts for the diffusion and reaction influences known to occur with all modern fumigants under concentration and exposure conditions relevant to industry. Copyright © 2009 CSIRO, Australia. Published by John Wiley & Sons, Ltd.  相似文献   

20.
The toxicity of allyl alcohol as a fumigant was assessed for adults ofTribolium castaneum (Herbst.),Rhyzopertha dominica (F.) andSitophilus oryzae (L.). Fumigations were carried out in 3.4–1 glass containers at concentrations of 1–15 mg/l for 3 h. The most sensitive species wasS. oryzae and the most tolerant wasT. castaneum. A dose of 15 mg/l for 3 h was lethal to all three species tested. The feasibility of proposing allyl alcohol as a candidate fumigant is discussed. Publication of the Agricultural Research Organization.  相似文献   

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