RESUMO
Insects and mites are common inhabitants and accidental invaders of food, including durable commodities, and their presence can have both direct and indirect effects on human health. The most common direct effect is contamination of food with arthropod fragments and related contaminants, which may be allergenic or even carcinogenic. The most important indirect effect is that their presence can change the storage microenvironment, making durable products suitable for the rapid development of fungi and other microorganisms. Some of these fungi can produce toxins (e.g., aflatoxins) that endanger human health. Insects may actively or passively contribute to the spread of microorganisms, increasing product contamination, and they may host bacteria that have developed antibiotic resistance, contributing to their spread in food. Several species also may host, attract, or transmit tapeworms, predators, or parasitoids that may affect health. This review synthesizes research on these topics and suggests directions for future research.
Assuntos
Parasitologia de Alimentos , Insetos , Ácaros , Animais , Vetores Artrópodes , Microbiologia de Alimentos , Armazenamento de AlimentosRESUMO
Psocids have emerged as worldwide pests of stored commodities during the past two decades, and are difficult to control with conventional management tactics such as chemical insecticides. Therefore, it is necessary to investigate alternative management strategies, such as the use of attractants for monitoring and controlling psocids, which can be incorporated into integrated pest management programs for psocids. Using a two-choice pitfall test, we studied the response of adults of different ages and sexes of Liposcelis entomophila (Enderlein) (Psocoptera: Liposcelididae), Liposcelis paeta Pearman, Liposcelis decolor (Pearman), Liposcelis brunnea Motschulsky, Liposcelis corrodens (Heymons), and Lepinotus reticulatus Enderlein (Psocoptera: Trogiidae) to volatiles from different potential attractants including grains, grain-based oils, brewer's yeast, wheat germ, and commercially available kairomone lures. For all species tested, sex and age did not have a major influence on response to the different potential attractants. Brewer's yeast most consistently elicited the strongest response for psocids, but this response frequently was not different from that to wheat germ and wheat germ oil. The percentage response to brewer's yeast varied among the psocid species tested: L. decolor (73-78%), L. entomophila (62-73%), L. brunnea (64-68%), L. paeta (42-57%), Lep. reticulatus (40%), and L. corrodens (15-19%). Two psocids species (L. corrodens and Lep. reticulatus) had low responses to all the potential attractants evaluated compared with the other four species. These results show there is high potential for using these attractants in a psocid-monitoring program.
Assuntos
Controle de Insetos/métodos , Insetos/efeitos dos fármacos , Insetos/fisiologia , Feromônios/farmacologia , Animais , Grão Comestível/química , Feminino , Insetos/crescimento & desenvolvimento , Masculino , Óleos Voláteis/farmacologia , Orientação/efeitos dos fármacos , Óleos de Plantas/farmacologia , Saccharomyces cerevisiae/química , Especificidade da EspécieRESUMO
The psocid species Liposcelis paeta Pearman, Liposcelis entomophila (Enderlein), Liposcelis decolor (Pearman), Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelididae), and Lepinotus reticulatus Enderlein (Psocoptera: Trogiidae) were evaluated in laboratory bioassays to determine their susceptibility to six concentrations of methyl bromide (0.027, 0.113, 0.280, 0.393, 0.452, and 0.616 g/m3) after 48 h of exposure at 27.5°C. The life stages that were evaluated were adults (for all species), nymphs (for all species except Lep. reticulatus), and eggs (for L. entomophila, L. decolor, and L. bostrychophila). Adults and nymphs were very susceptible, and complete mortality was recorded at concentrations between 0.027 and 0.280 g/m3. In contrast, eggs were by far more tolerant than adults and nymphs for all species tested. At 0.027 g/m3, mortality did not exceed 53%, while survival was high even at 0.113 g/m3. Complete (100%) egg mortality was recorded at 0.393 g/m3 for L. decolor and at 0.452 g/m3 for L. entomophila and L. bostrychophila; concentrations estimated to give 99% mortality for eggs of these three species were 0.710, 1.044, and 0.891 g/m3, respectively. These results show that stored-product psocids are susceptible to methyl bromide, but concentrations of ≥0.452 g/m3 should be used to control all life stages.
Assuntos
Hidrocarbonetos Bromados , Controle de Insetos , Insetos , Inseticidas , Animais , Relação Dose-Resposta a Droga , Contaminação de Alimentos/prevenção & controle , Fumigação , Insetos/crescimento & desenvolvimento , Resistência a Inseticidas , Ninfa/crescimento & desenvolvimento , Óvulo/crescimento & desenvolvimentoRESUMO
Previously regarded as minor nuisance pests, psocids belonging to the genus Liposcelis now pose a major problem for the effective protection of stored products worldwide. Here we examine the apparent biological and operational reasons behind this phenomenon and why conventional pest management seems to be failing. We investigate what is known about the biology, behavior, and population dynamics of major pest species to ascertain their strengths, and perhaps find weaknesses, as a basis for a rational pest management strategy. We outline the contribution of molecular techniques to clarifying species identification and understanding genetic diversity. We discuss progress in sampling and trapping and our comprehension of spatial distribution of these pests as a foundation for developing management strategies. The effectiveness of various chemical treatments and the availability and potential of nonchemical control methods are critically examined. Finally, we identify research gaps and suggest future directions for research.
Assuntos
Controle de Insetos , Insetos , Inseticidas , Animais , Controle de Insetos/métodos , Insetos/efeitos dos fármacos , Insetos/microbiologia , Insetos/fisiologia , Resistência a Inseticidas , Inseticidas/farmacologiaRESUMO
Traps baited with pheromones are used to monitor the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera-Tenebrionidae), populations in flour mills to aid in making pest management decisions, but the factors that influence T. castaneum movement are not fully understood. We investigated the impact of photoperiod, light intensity, temperature, and relative humidity on flight initiation. The percentage of adults initiating flight reached a maximum at 30 -35 degrees C, and then fell to zero at 22.5 and 45 degrees C. Only 2% of beetles flew in complete darkness, and the number of beetles initiating flight increased to 41% under 18 h of light and then decreased slightly to 37% under 24 h of light. Rates of flight initiation did not vary with light intensities from 1,784 to 4,356 lux or relative humidities from 25 to 85%. Thus, temperature and photoperiod are the main abiotic factors tested that impact flight initiation in T castaneum, which have broad ranges of temperatures and photoperiods over which they can fly. The current results should be useful in helping to interpret trap catches based on abiotic conditions during the trapping period, and the results should be useful in helping to understand T. castaneum movement outside grain storages and processing facilities and their potential to infest structures.
Assuntos
Voo Animal , Tribolium/fisiologia , Animais , Fotoperíodo , Tempo (Meteorologia)RESUMO
The residual effect of chlorfenapyr (Phantom) was evaluated for residual control of three stored-product psocid species: Liposcelis bostrychophila Badonnel, Liposcelis entomophila (Enderlein), and Liposcelis paeta Pearman (Psocoptera: Liposcelididae). Chlorfenapyr was applied to individual arenas with a concrete surface at rates of 0, 2.8, 13.8, 20.6, 27.5, 55, and 110 mg active ingredient (AI)/m2. Adults were exposed on the treated arenas and mortality assessed after 1, 2, and 3 d. The procedures were repeated weekly on the same treated arenas for 3 wk to assess residual efficacy. At each week, mortality of all species was low after 1 d of exposure but notably increased after 2 or 3 d. L. entomophila was the most susceptible species, with 99-100% mortality at rates of 13.8 mg/m2 or higher. Similarly, mortality of L. paeta after 3 d of exposure at the same concentration ranged from 92 to 100%. L. bostrychophila was the least susceptible species, with mortality of < 60% during the third week after application at rates < or = 27.5 mg/m2. However, even for this species, mortality after 3 wk was 90% or higher at rates > 27.5 mg/m2. Complete mortality of all species occurred after 3 d exposure at the highest rate tested of 110 mg/m2. Thus, our results show that chlorfenapyr is effective against major psocid species at the application rates evaluated in this study.
Assuntos
Contaminação de Alimentos/prevenção & controle , Controle de Insetos/métodos , Insetos , Inseticidas , Resíduos de Praguicidas , Piretrinas , Animais , Especificidade da EspécieRESUMO
The psocid, Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelididae), can cause significant damage to stored commodities, and its pest status in the United States has been increasing over the last decade. Because L. bostrychophila is difficult to control with conventional methods, it is critical to explore alternative approaches such as the use of attractants that can be incorporated into integrated pest management programs for monitoring psocids. The orientation response of several L. bostrychophila life stages (first and second instars, third and fourth instars, 0- to 7-d-old adults, 21- to 28-d-old adults, and adults of mixed ages) to a range of potential attractants (including whole and cracked grains, grain-based oils, wheat germ, brewer's yeast, and commercially available kairomone lures) was studied using a two-choice pitfall test to identify candidates for further development as lures in traps. Among the potential attractants evaluated, the strongest response by all stages of L. bostrychophila was to brewer's yeast. Other materials for which there was consistently a strong response were psocid diet, wheat germ, and wheat germ oil. These results show the potential for developing monitoring tools for integrated pest management programs for L. bostrychophila and other psocid species.
Assuntos
Controle de Insetos/métodos , Insetos/efeitos dos fármacos , Insetos/fisiologia , Feromônios/farmacologia , Animais , Grão Comestível/química , Feminino , Insetos/crescimento & desenvolvimento , Ninfa/efeitos dos fármacos , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Óleos Voláteis/farmacologia , Orientação/efeitos dos fármacos , Óleos de Plantas/farmacologia , Saccharomyces cerevisiae/químicaRESUMO
The insecticidal effect of Temprid, a formulation that contains beta-cyfluthrin and imidacloprid, was tested on concrete for control of seven stored-product insect species: the rusty grain beetle, Cryptolestes ferrugineus (Stephens); the sawtoothed grain beetle, Oryzaephilus surinamensis (L.); the red flour beetle, Tribolium castaneum (Herbst); the confused flour beetle, T. confusum Jacquelin du Val; the hide beetle, Dermestes maculatus (DeGeer); and the psocids Liposcelis bostrychophila Badonnel and L. paeta Pearman. Temprid, which contains 10.5% beta-cyfluthrin and 21% imidacloprid, was tested at the rate of 17.2 ml of formulation/4.1 liters of water/100 m2. Adults were exposed for 4, 8, 14, and 24 h, and then daily for 7 d, on untreated dishes or dishes treated with Temprid. In the untreated dishes, mortality of C. ferrugineus and O. surinamensis was lower when food was present, but food did not affect mortality of the other species. Presence of food did not affect mortality of any of the species tested in the treated dishes. C. ferrugineus, O. surinamensis, and the two psocid species were very susceptible to Temprid, with mortality of 97-100% after 7 d of exposure. In contrast, D. maculatus, T. castaneum, and T. confusum were tolerant to Temprid, as mortality did not exceed 57, 25, and 17%, respectively, at the 7-d exposure. A separate series of similar bioassays with Tempo, a formulation that contains 11.8% beta-cyfluthrin alone, which was applied at the same dose rate as Temprid, was conducted using O. surinamensis and T. castaneum as the target insect species, and results showed that Tempo was at least as effective as Temprid. Our results indicate that the simultaneous use of beta-cyfluthrin with imidacloprid is not more effective on concrete than beta-cyfluthrin alone, and efficacy of both formulations varies with the target species.
Assuntos
Imidazóis , Insetos , Inseticidas , Nitrilas , Nitrocompostos , Piretrinas , Animais , Besouros , Materiais de Construção , Neonicotinoides , Especificidade da EspécieRESUMO
With the phase-out and impending ban of methyl bromide, sulfuryl fluoride is among the most promising alternative fumigant insecticides for control of stored-product insect pests. It has been evaluated for control of several stored-product insect pests, but there are few data available on its efficacy for control of stored-product psocids (Psocoptera). We evaluated sulfuryl fluoride for control of different life stages of the psocids Liposcelis paeta Pearman, L. entomophila (Enderlein), L. bostrychophila Badonnel, L. decolor Pearman, and Lepinotus reticulatus Enderlein (Trogiidae) in 48-hr trials at 27.5 degrees C. Adults and nymphs were susceptible to sulfuryl fluoride. Complete (100%) adult and nymphal mortality was recorded at concentrations between 4 and 8 g/m3, except for L. decolor for which all adults were only killed at 24 g/m3. Eggs were tolerant to sulfuryl fluoride. Complete egg mortality was achieved at 24 and 72 g/m3 for L. reticulatus and L. decolor, respectively. Survival of L. paeta eggs was recorded even after exposure to 96 g/m3. Given that the highest United States label concentration for sulfuryl fluoride for a 48-h exposure interval is 31.25 g/m3, our study indicates that high doses and/or longer exposures are needed for complete mortality of eggs of L. decolor and L. paeta. Moreover, the present work suggests that there is considerable variation in efficacy of sulfuryl fluoride for control of different psocid species.
Assuntos
Controle de Insetos/métodos , Insetos/efeitos dos fármacos , Inseticidas/farmacologia , Ácidos Sulfínicos/farmacologia , Animais , Relação Dose-Resposta a Droga , Ninfa/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Especificidade da EspécieRESUMO
The efficacies of commercial methoprene and esfenvalerate aerosols for control of stored-product psocid pests were evaluated in simulated field studies. The efficacies of methoprene, esfenvalerate EC, the carrier Isopar-M™, and a combination of methoprene and esfenvalerate aerosols for control of Liposcelis decolor (Pearman) (Psocoptera: Liposcelididae) and Liposcelis entomophila (Enderlein) nymphs were assessed, and the effects of direct and indirect exposure of Liposcelis bostrychophila Badonnel, L. decolor, and Liposcelis paeta Pearman adults to esfenvalerate EC aerosol were evaluated. The greatest nymphal mortality attained was 76%, indicating that the four aerosols tested were ineffective against L. decolor and L. entomophila nymphs. In the direct and indirect exposure studies, the greatest adult mortalities attained for the three psocid species were 62 and 32%, respectively. Based on these data, esfenvalerate aerosol is ineffective for control of L. bostrychophila, L. decolor, L. entomophila, and L. paeta psocid species. This study shows that methoprene, esfenvalerate EC, and a combination of methoprene and esfenvalerate aerosols were ineffective against the four psocid species tested when applied at rates that are usually effective against other stored-product insect pests.
Assuntos
Controle de Insetos , Insetos , Inseticidas , Hormônios Juvenis , Metoprene , Nitrilas , Piretrinas , Aerossóis , Animais , Ninfa , Especificidade da EspécieRESUMO
Tests were conducted to determine whether the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae), selects rough rice (Oryza sativa L. (Poales: Poaceae)) kernels with cracked hulls for reproduction when these kernels are mixed with intact kernels. Differing amounts of kernels with cracked hulls (0, 5, 10, and 20%) of the varieties Francis and Wells were mixed with intact kernels, and the number of adult progeny emerging from intact kernels and from kernels with cracked hulls was determined. The Wells variety had been previously classified as tolerant to R. dominica, while the Francis variety was classified as moderately susceptible. Few F 1 progeny were produced in Wells regardless of the percentage of kernels with cracked hulls, few of the kernels with cracked hulls had emergence holes, and little firass was produced from feeding damage. At 10 and 20% kernels with cracked hulls, the progeny production, number of emergence holes in kernels with cracked hulls, and the amount of firass was greater in Francis than in Wells. The proportion of progeny emerging from kernels with cracked hulls increased as the proportion of kernels with cracked hulls increased. The results indicate that R. dominica select kernels with cracked hulls for reproduction.
Assuntos
Besouros/fisiologia , Oryza/anatomia & histologia , Animais , Besouros/crescimento & desenvolvimento , Comportamento Alimentar , Feminino , Larva , Masculino , Oviposição , Sementes/anatomia & histologiaRESUMO
Effects of rearing density, adult density and sex ratio in the flight chamber, adult age, sex, presence or absence of food, and duration of food deprivation on rate of and time to flight initiation of the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), were studied in the laboratory. Rates of flight initiation were slightly lower at lower rearing densities, but they did not differ with age or sex of adults, presence or absence of food in the flight chamber, or duration of food deprivation. Focal adults were less likely to fly when individuals of the opposite sex were present in flight chambers. Presence of the same sex or mixed sexes and numbers of individuals in flight chambers did not affect tendency to fly of focal individuals. Mean time to flight of older beetles (7-20 d old) was less than that of younger beetles (1-4 d old). No young beetles flew during the first 24 h of flight tests. Mean time to flight did not differ with rearing density, sex, presence or absence of food, or duration of food deprivation. Our results indicate that this species is highly dispersive during the adult stage and that flight does not seem to be associated with just prereproductive or postreproductive dispersal phases, high rearing density, or short to medium periods of food deprivation. Therefore, T. castaneum level of flight activity does not seem to be associated with factors that have been shown in the literature to increase dispersal by walking for this species and to increase flight initiation in other stored-product species.
Assuntos
Voo Animal , Privação de Alimentos , Tribolium/fisiologia , Fatores Etários , Animais , Feminino , Masculino , Densidade Demográfica , Fatores SexuaisRESUMO
The insect growth regulator pyriproxyfen was evaluated as a surface treatment for control of three stored-product psocid pests Liposcelis bostrychophila Badonnel, Liposcelis decolor (Pearman), and Liposcelis paeta Pearman (Psocoptera: Liposcelididae). Nymphs were exposed for 35 d on a concrete surface treated with 2.3 mg of active ingredient/m2 pyriproxyfen. Exposure to pyriproxyfen significantly reduced the numbers of both adults and nymphs in comparison with untreated controls. In adults, the greatest reduction (> 90%) was for L. decolor and L. bostrychophila, whereas for L. paeta it was 49%. Few adults of any species were found in the pyriproxyfen treatments. The greatest numbers of nymphs were recorded for L. bostrychophila for both pyriproxyfen treatments and controls. Few adults of any species were found in the pyriproxyfen treatments. The results indicate that pyriproxyfen is effective for control of L. bostrychophila, L. decolor, and L. paeta on concrete, and although complete control was not achieved, the results warrant further long-term study to determine whether pyriproxyfen can completely eliminate psocid populations over time.
Assuntos
Contaminação de Alimentos/prevenção & controle , Controle de Insetos/métodos , Insetos , Inseticidas , Piridinas , Animais , Materiais de Construção , Estágios do Ciclo de Vida , Especificidade da EspécieRESUMO
Stored-product insects can cause postharvest losses, estimated from up to 9% in developed countries to 20% or more in developing countries. There is much interest in alternatives to conventional insecticides for controlling stored-product insects because of insecticide loss due to regulatory action and insect resistance, and because of increasing consumer demand for product that is free of insects and insecticide residues. Sanitation is perhaps the first line of defense for grain stored at farms or elevators and for food-processing and warehouse facilities. Some of the most promising biorational management tools for farm-stored grain are temperature management and use of natural enemies. New tools for computer-assisted decision-making and insect sampling at grain elevators appear most promising. Processing facilities and warehouses usually rely on trap captures for decision-making, a process that needs further research to optimize.
Assuntos
Grão Comestível/parasitologia , Parasitologia de Alimentos , Insetos , Controle Biológico de Vetores , Animais , Ambiente ControladoRESUMO
The Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), is a common pest of stored corn, Zea mays L. We developed a computer model to simulate population development of the Indianmeal moth in stored corn by using previously published data describing immature developmental times and survivorship, and adult longevity and fecundity. The model accurately simulated population development of Indianmeal moths in corn stored during fall and into winter of three separate storage seasons in South Carolina. This is the period when the Indianmeal moth is a pest in stored corn in South Carolina. The model predicted that populations would increase after winter as grain temperatures rose, but observed populations in the grain bins never increased after winter. Despite this, the model should be useful from a management perspective because the corn is being sold off or used up after winter, and the observed Indianmeal moth populations never reached damaging levels after winter.
Assuntos
Simulação por Computador , Modelos Biológicos , Mariposas/fisiologia , Zea mays/parasitologia , Animais , Contaminação de Alimentos , Conservação de AlimentosRESUMO
The effect of short exposures to spinosad-treated wheat, Triticum aestivum L., or maize, Zea mays L., was evaluated against adults of four stored-product insect species: lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae); rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae); red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae); and the psocid Lepinotus reticulatus (Enderlein) (Psocoptera: Trogiidae). Adult mortality of these species was recorded after 0, 2, 4, 8, 16, and 40 h on commodities treated with 1 ppm of spinosad (immediate mortality). Then, the surviving individuals were removed and placed on untreated wheat or maize, and mortality was recorded again 7 d later (delayed mortality). Progeny production then was determined 65 and 35 d later for the beetles and psocids, respectively. Among the four species tested, R. dominica was the most susceptible, and immediate mortality after 40 h reached 78 and 72% on wheat and maize, respectively. Moreover, 7 d later, all adults that had been exposed for >2 h were dead on both commodities. Progeny production was significantly reduced in comparison with the controls, and no progeny were found when parental adults had been exposed for >8 or >4 h on wheat and maize, respectively. For S. oryzae, 40-h exposures significantly increased delayed mortality on both wheat and maize, but progeny production still was high. Generally, no effect of short exposures was noted for T. castaneum. For L. reticulatus, despite the fact that the increase of exposure interval increased mortality on maize, progeny production was not avoided. With the exception of T. castaneum, more progeny were found on wheat than on maize. The results of the current study indicate that R. dominica is very susceptible after short exposures to spinosad-treated substrate, but the other species are able to survive and reproduce at the exposure range examined.
Assuntos
Insetos/efeitos dos fármacos , Macrolídeos/farmacologia , Triticum/química , Zea mays/química , Animais , Combinação de Medicamentos , Conservação de Alimentos , Macrolídeos/química , Fatores de TempoRESUMO
Differences in stored-product psocid progeny production as a function of commodity type, percentage of cracked kernels, and wheat class were examined using laboratory bioassays. Population growth of Liposcelis bostrychophila Badonnel, Liposcelis decolor (Pearman), Liposcelis paeta Pearman, and Liposcelis entomophila (Enderlein) (Psocoptera: Liposcelididae) was highest on sorghum Sorghum bicolor (L.) Moench, followed by wheat, Triticum aestivum L., and rice, Oryza sativa L., whereas progeny production was negligible on wheat germ. In a second experiment that did not include L. entomophila, population growth was examined on wheat containing 0, 1, 5, 10, 20, 50, and 100% cracked kernels. Progeny production did not increase as cracked kernel content increased. Instead, progeny production peaked at 20% for L. bostrychophila adults and nymphs, at 10% for L. decolor, and at 50% for L. paeta adults; no further increases were noted beyond these levels of cracked wheat content. In a third experiment that did not include L. entomophila, progeny production was examined on eight classes of wheat: hard red winter, hard red spring, soft white winter, soft white spring, soft club, durum, soft red winter, and hard white. Overall, progeny production was higher on durum wheat than on the other classes. The results indicate that there are considerable variations in psocid population growth among the different commodities tested, and this information may be used to predict the degree to which stored commodities are susceptible to psocid infestation.
Assuntos
Insetos/fisiologia , Triticum , Animais , Crescimento Demográfico , SementesRESUMO
We evaluated the efficacy of three diatomaceous earth (DE) formulations, Dryacide, Protect-It, and Insecto, against three Psocoptera species, Liposcelis entomophila (Enderlein) (Liposcelididae), Lepinotus reticulatus Enderlein (Trogiidae), and Liposcelis decolor (Pearman), in the laboratory. Bioassays were conducted in three grain commodities, wheat, rice and maize, at 30 degrees C and 75% RH, and the DEs were applied at the recommended dose rates of 1,000, 400, and 500 ppm for Dryacide, Protect-It, and Insecto, respectively. Differences in adult mortality were found among grains and DEs for L. entomophila and L. reticulatus, but these trends were not consistent for all combinations tested. Type of grain and DE did not affect L. decolor mortality significantly. Moreover, mortality increased with increasing exposure time for L. entomophila and L. reticulatus, but there was no effect of exposure time on L. decolor. After 7 d of exposure, mortalities of L. entomophila, L. reticulatus, and L. decolor were 56, 55, and 40%, respectively, and the respective mortality levels after 14 d were 63, 71, and 42%. Progeny production after 30 d was significantly suppressed for all species in the treated grains. However, progeny production was still high in the treated grains and reached 54, 42, and 76 individuals/10 g of grain for L. entomophila, L. reticulatus, and L. decolor, respectively. Progeny production did not vary with commodity. Our results suggest that DEs, when used alone, will not provide effective control of psocids.
Assuntos
Terra de Diatomáceas , Insetos , Inseticidas , Oryza , Triticum , Zea mays , Animais , Controle de Insetos/métodos , Mortalidade , Especificidade da EspécieRESUMO
BACKGROUND: The psocids Liposcelis bostrychophila Badonnel and L. entomophila (Enderlein) (Liposcelididae) are emerging pests of stored products. Although their behavior, particularly their high mobility, may contribute to the reported relatively low efficacy of insecticides against them, studies to investigate this have not been conducted. The present study aimed to assess the label rate efficacy of three commercial insecticides (beta-cyfluthrin, chlorfenapyr and pyrethrins) applied on concrete surfaces against L. bostrychophila and L. entomophila, and also their sublethal effect on the mobility of these species. RESULTS: The synthetic insecticides beta-cyfluthrin and chlorfenapyr showed high short-term efficacy (LT(95)
Assuntos
Comportamento Animal/efeitos dos fármacos , Insetos/efeitos dos fármacos , Inseticidas/farmacologia , Locomoção/efeitos dos fármacos , Animais , Nitrilas/farmacologia , Piretrinas/farmacologia , Fatores de TempoRESUMO
Insect infestations in stored grain cause extensive damage worldwide. Storage insect pests, including the Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae); Sitophilus spp. (Coleoptera: Curculionidae); and their natural enemies [e.g., Cephalonomia tarsalis (Ashmead) (Hymenoptera: Bethylidae), and Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae)] inhabit a temporary, but stable ecosystem with constant environmental conditions. The objective of the present experiment was to assess the efficacy of using ethylene glycol antifreeze in combination with nutrient solutions to monitor storage insect pest and natural enemy populations in three bins of corn, Zea mays L. The treatments were deionized water, a diluted (1:5 antifreeze:water) antifreeze solution, 10% honey, 10% honey in the diluted antifreeze solution, 10% beer in the diluted antifreeze solution, 10% sucrose in the diluted antifreeze solution, and a commercial pheromone trap suspended in a 3.8-liter container filled with 300-ml of diluted antifreeze solution. The seven treatments captured storage insect pests and their natural enemies in the bins at 33-36 degrees C and 51-55% RH. The pheromone trap in the container with the diluted antifreeze captured significantly more P. interpunctella than the other treatments, but a lower percentage (7.6%) of these captures were females compared with the rest of the treatments (> 40% females). All trapping solutions also captured Sitophilus spp. and other beetle species, but the captures of the coleopteran pests were not significantly different among the seven treatments (P > 0.05). Two parasitoid wasps also were captured in the study. The number of A. calandrae was different among the seven treatments (P < 0.05), whereas the number of C. tarsalis was not different among the treatments (P > 0.05). Most A. calandrae adults were captured by the 10% honey in the diluted antifreeze, whereas the fewest were captured in the deionized water. Microbial growth was observed in the 10% honey solution, but no microbial growth occurred in the rest of the treatments, including 10% honey in the diluted antifreeze solution. The results of insect captures and microbial growth demonstrated that antifreeze could be used as a part of storage insect monitoring and/or control programs.