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1.
An Acad Bras Cienc ; 91(3): e20181008, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31432904

RESUMO

Leaf-cutting ants are considered major pests of agriculture and forestry in the Neotropics. Attractive toxic baits are the prevailing method for managing them. Thus, there is great interest in identifying attractants to incorporate into these baits. Moreover, leaf-cutting ants can avoid toxic baits by associating the attractant with the toxin. We evaluated attractiveness of heptyl butyrate, a volatile compound found in fresh apples and plums. We conducted field experiments with ten colonies of Acromyrmex lobicornis. First, we evaluated the behaviour of ants exposed to heptyl butyrate at 1% by surrounding resources. Then, we compared the attractiveness of heptyl butyrate and orange pulp, the most commonly used attractant. Finally, we evaluated whether heptyl butyrate increases the attractiveness of a carbohydrate resource at varying doses. Heptyl butyrate at 1% attracted 92% more ants than the control and that it was as attractive as orange pulp. Heptyl butyrate paired with sucrose at concentrations of 0.001 and 0.1% was more attractive than sucrose alone, but greater concentrations did not increase sucrose's attractiveness. Therefore, heptyl butyrate could be added to toxic baits to manage A. lobicornis as it is as attractive as the most commonly used attractant and can be applied directly to the pellets.


Assuntos
Formigas/efeitos dos fármacos , Controle de Insetos/métodos , Feromônios/química , Animais , Bioensaio , Feromônios/isolamento & purificação , Feromônios/farmacologia
2.
J Chem Ecol ; 45(7): 626-637, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31257561

RESUMO

Since the first reports of damage by Drosophila suzukii, the spotted-wing Drosophila (SWD), over a decade ago in Europe, widespread efforts have been made to understand both the ecology and the evolution of this insect pest, especially due to its phylogenetic proximity to one of the original model organisms, D. melanogaster. In addition, researchers have sought to find economically viable solutions for the monitoring and management of this agricultural pest, which has now swept across much of Europe, North America and Asia. In a new direction of study, we present an investigation of plant-based chemistry, where we search for natural compounds that are structurally similar to known olfactory cues from parasitoid wasps that in turn are well-described ovipositional avoidance cues for many Drosophila species. Here we test 11 plant species across two plant genera, Nepeta and Actinidia, and while we find iridoid compounds in both, only those odorants from Actinidia are noted to be detected by the insect antenna, and in addition, found to be behaviorally active. Moreover, the Actinidia extracts resulted in oviposition avoidance when they were added to fruit samples in the laboratory. Thus we propose the possible efficacy of these plants or their extracted chemistry as a novel means for establishing a cost-effective integrated pest management strategy towards the control of this pest fly.


Assuntos
Actinidia/química , Produtos Biológicos/química , Drosophila/fisiologia , Controle de Insetos/métodos , Nepeta/química , Actinidia/metabolismo , Actinidia/parasitologia , Animais , Produtos Biológicos/farmacologia , Produtos Agrícolas , Drosophila/efeitos dos fármacos , Drosophila/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Nepeta/metabolismo , Nepeta/parasitologia , Oviposição/efeitos dos fármacos , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia
3.
Microbiol Res ; 226: 41-47, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284943

RESUMO

Myzus persicae Sulzer (Hemiptera: Aphididae), is a generalist cosmopolitan insect that infests more than 400 plant species of 40 different families and is one of the major pests infesting potato crops. It causes direct damage and also spread plant viruses. The intensive use of synthetic insecticide to control aphids has led to resistant populations. Therefore, there is a need to develop biopesticides for effective control that minimizes environmental hazards. The bacteria Bacillus amyloliquefaciens is recognized as a producer of a variety of bioactive compounds. The aim here was to evaluate the aphicidal effect of B. amyloliquefaciens strains, CBMDDrag3, PGPBacCA2, and CBMDLO3, and their metabolites on the mortality and fecundity of M. persicae. Cells suspensions, heat-killed cell suspensions, cell-free supernatants, or isolated lipopeptide fractions from B. amyloliquefaciens strains were offered to aphids through artificial diets. The isolated lipopeptide fractions composed mainly of kurstakins, surfactins, iturins, and fengycins, when were administrated through diets, had no aphicidal effect against M. persicae. However, aphids fed on diets with whole cell suspensions and its cell-free supernatant of all three bacteria strains resulted in 100% mortality of adult aphids and nymphs. Specially, B. amyloliquefaciens CBMDLO3, has an effective aphicidal effect on M. persicae, used both bacterial cells and their metabolites. Moreover, heat-killed cells of B. amyloliquefaciens CBMDLO3 also had aphicidal action, although the aphid mortality was lower than on diet with living bacteria. Therefore, these results propose that B. amyloliquefaciens, could function as a novel eco-friendly biopesticide for the control of M. persicae.


Assuntos
Afídeos/efeitos dos fármacos , Afídeos/microbiologia , Bacillus amyloliquefaciens/metabolismo , Controle Biológico de Vetores , Animais , Bacillus amyloliquefaciens/isolamento & purificação , Agentes de Controle Biológico/isolamento & purificação , Agentes de Controle Biológico/metabolismo , Agentes de Controle Biológico/farmacologia , Feminino , Controle de Insetos/métodos , Inseticidas/isolamento & purificação , Inseticidas/metabolismo , Inseticidas/farmacologia , Lipopeptídeos/isolamento & purificação , Lipopeptídeos/metabolismo , Lipopeptídeos/farmacologia , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle
4.
J Insect Sci ; 19(2)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31222325

RESUMO

Bioassays were conducted to assess the individually insecticidal activities of hexane, acetone, and methanol extracts from Hemizygia welwitschii Rolfe-Ashby leaves powder against Callosobruchus maculatus (F.). The extracts were applied at 2, 4, 6, and 10 g/kg of cowpea and the untreated seeds served as negative control. Treatments were arranged in a complete randomized design with four replications. Adult mortality, F1 progeny emergence, as well as insect population increase, seeds damage, and seeds germination were carried out. The results obtained showed that the three extracts of H. welwitschii were very effective in protecting stored cowpea against C. maculatus at the highest dosage (10 g/kg) 7 d after treatment. There was no F1 progeny emergence of C. maculatus in cowpea treated with hexane extract at the dosage of 10 g/kg, while, at the same dosage, acetone and methanol extracts almost completely inhibited the F1 progeny emergence. Also, the different concentration levels significantly protected the seeds with regard to seed damage caused by C. maculatus compared with the untreated control after 3 mo storage. The viability of seeds was not affected by the extracts. Because of their effectiveness, the three extracts of H. welwitschii leaves powder could be a good candidate in pest management programs, especially against C. maculatus in stored cowpea grains, in Cameroon and other developing countries.


Assuntos
Besouros , Controle de Insetos/métodos , Lamiaceae/química , Extratos Vegetais/química , Animais , Testes de Toxicidade , Vigna
5.
J Sci Food Agric ; 99(13): 5962-5968, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31215022

RESUMO

BACKGROUND: Cadra (=Ephestia) cautella (Walker) is a serious cosmopolitan pest that can feed on a wide variety of stored foods. It is controlled mainly by fumigation with phosphine, to which strong resistance has been documented in major stored-product insects in many countries. The need for reliable, user- and environmentally friendly alternatives is therefore high on the agenda to avoid the development of potential resistance and to reduce human exposure to toxic insecticides. Two modified atmospheres (MAs) composed of high carbon dioxide (CO2 ) and low oxygen (O2 ) (90% and 96% CO2 in air) were studied at the laboratory at 20 °C and 65 ± 3% relative humidity (RH) against C. cautella. RESULTS: Eggs (1, 2, and 3 days old), young and mature larvae (10 and 20 days old), pupae (1, 2 and 3 days old) and adults (1 day old) were exposed to two MAs consisting of high CO2 and low O2 for the range of 2 to 104 h. Eggs, old larvae, and pupae were found to be the most tolerant. Adults were rather easily killed and young larvae were the most susceptible. Lethal exposure time (LT99 ) values were between 11.74 h and 128.97 h. CONCLUSION: Modified atmospheres consisting of high CO2 and low O2 offer an affordable combination to control C. cautella effectively. From the perspective of economics and efficacy, 90% CO2 might be the concentration of choice. © 2019 Society of Chemical Industry.


Assuntos
Dióxido de Carbono/farmacologia , Controle de Insetos/métodos , Mariposas/efeitos dos fármacos , Animais , Atmosfera/análise , Dióxido de Carbono/análise , Controle de Insetos/instrumentação , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Oxigênio/análise , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento
6.
Environ Sci Pollut Res Int ; 26(21): 21871-21881, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31134551

RESUMO

Utilization of non-host plants semiochemicals to mediate insect behavior offers a promising opportunity for novel management of insect pests in field crops and fruits. Therefore, there is still a substantial opportunity for the development of natural prophylactic as an eco-friendly approach in the novel pest management programs. Sophora alopecuroides extract has been used as a natural pesticide in the control of agricultural and household pests, but the low persistence effect and rapid biodegradability limit its use on a wider scale in pest management programs. In this study, an emulsifiable concentrate formulation containing S. alopecuroides extract (SAE-EC) was developed with a simple procedure and evaluated for its ovicidal, antifeedant, and repellent effects against Diaphorina citri under laboratory and semi-field conditions. Our results indicated that SAE-EC at 15, 30, and 50 mg/mL concentrations provide complete protection against psyllids for a period of 96 h after application both under laboratory and semi-field conditions, while the aqueous methanolic extract of S. alopecuroides loses its persistence 48 h after application. Furthermore, the emulsifiable concentrate at 20 and 30 mg/mL concentrations, only 15.97% and 31.97% of eggs were able to hatch, and at similar concentrations, 72.86% and 85.5% of honeydew secretion were reduced as compared to the control. SAE-EC at 30 mg/mL concentration has not shown any phytotoxic symptoms on Murraya paniculata seedlings. Fourier transform infrared (FTIR) study revealed the presence of alkaloids in emulsifiable concentrate after 3 months of its preparation placed under ambient temperature. Furthermore, the particle size and polydispersity index (PDI) of the emulsifiable concentrate were also confirmed by dynamic light scattering (DLS). Our finding indicated that emulsifiable concentrate formulation prolongs the persistence of S. alopecuroides extract and enhances its efficacy both under laboratory and semi-field conditions. It has been concluded that the emulsifiable concentrate formulation containing S. alopecuroides extract might be developed as an eco-friendly novel prophylactic against citrus psyllid.


Assuntos
Hemípteros/efeitos dos fármacos , Repelentes de Insetos/farmacologia , Extratos Vegetais/farmacologia , Sophora/química , Alcaloides/análise , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Difusão Dinâmica da Luz , Emulsões/química , Emulsões/farmacologia , Hemípteros/fisiologia , Controle de Insetos/métodos , Repelentes de Insetos/administração & dosagem , Repelentes de Insetos/química , Murraya/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Plântula/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Zigoto/efeitos dos fármacos
7.
An Acad Bras Cienc ; 91(2): e20180375, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31141011

RESUMO

Drosophila suzukii is one of the main pests of small fruits in the world. An effective monitoring is fundamental to detect the presence of the fly and to predict the infestation of fruits in new areas. We evaluated the food baits Ceratrap®, Torula®, Biofruit®, Suzukii Trap®, apple cider vinegar, and a homemade mixture comprising wine, vinegar and molasses (WVM) for D. suzukii attractiveness, and if reproductive stage affects females attraction and capture in the different baits. Bait selectivity of non-target insects was assessed. The preference of adults between ripe blackberry fruit and the food baits was also evaluated. Adults showed a higher attraction (61.97% of the captured insects) to the WVM mixture than to Ceratrap® (1.32%), Torula® (0.52%), Biofruit® (13.15%), Suzukii Trap® (17.6%), and apple vinegar (5.4%). Considering the attractiveness to D. suzukii, Suzukii Trap® and apple vinegar were the most selective to non-target insects. In general, reproductively immature females showed a preference for Biofruit®, apple vinegar, and WVM, whereas mature females did not show bait preferences. Adults preferred ripe blackberry fruit over the WVM mixture. Understanding the field behavior of D. suzukii is of foremost importance to estimate insect population density and outline pest management strategies.


Assuntos
Drosophila/fisiologia , Controle de Insetos/métodos , Feromônios , Animais , Brasil , Drosophila/classificação , Feminino , Controle de Insetos/instrumentação , Masculino
8.
Environ Sci Pollut Res Int ; 26(17): 17797-17808, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31037535

RESUMO

Efficacy of Metarhizium anisopliae strain (IMI330189) and Mad1 protein alone or in combination by feeding method to overcome immune-related enzymes and Toll-like pathway genes was investigated in migratory locust. M. anisopliae (IMI330189) is a potent and entomopathogenic fungal strain could be effectively used against insect pests. Similarly, Mad1 protein adheres to insect cuticle, causing virulence to insects. We confirmed maximum 55% of mortality when M. anisopliae (IMI330189) and Mad1 was applied in combination. Similarly, increased PO activity was observed in locust with combined dose of Mad1 + IMI330189 whereas PO, POD, and SOD activities reduced using Mad1 independently. Four Toll-like signaling pathway genes (MyD88, Cactus, Pelle, and CaN) were investigated from midgut and body of the migratory locust after 72 h of treatments. Subsequently, the expression of MyD88 in the midgut and body significantly decreased with the application of Mad1 and Mad1 + IMI330189. Performance of these treatments was absolutely non-consistent in both parts of insects. Meanwhile, IMI330189 significantly raised the expression of Cactus in both midgut and body. However, the combined treatment (Mad1 + IMI330189) significantly reduced the Cactus expression in both body parts. Pelle expression was significantly increased in the midgut with the application of independent treatment of Mad1 and IMI330189 whereas the combined treatment (Mad1 + IMI330189) suppressed the Pelle expression in midgut. Its expression level was absolutely higher in body with the application of IMI330189 and Mad1 + IMI330189 only. On the other hand, Mad1 significantly increased the expression of CaN in midgut. However, all three treatments significantly affected and suppressed the expression of CaN gene in body of locust. This shows that the applications of M. anisopliae and Mad1 protein significantly affected Toll signaling pathway genes, which ultimately increased level of susceptibility of locust. However, their effect was significantly different in both parts of locust which recommends that the Toll-related genes are conserved in midgut instead of locust body.


Assuntos
Proteínas Fúngicas/metabolismo , Gafanhotos/microbiologia , Metarhizium , Migração Animal , Animais , Genes de Insetos , Gafanhotos/enzimologia , Controle de Insetos/métodos , Insetos , Receptores Toll-Like/genética , Virulência
9.
Arch Insect Biochem Physiol ; 101(3): e21555, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31038785

RESUMO

RNAi-based pest control strategies are emerging as environment friendly and species-specific alternatives for the use of conventional pesticides. Because N-glycosylation is important for many biological processes, such as growth and development, the early steps of protein N-glycosylation are promising targets for an RNAi-based pest control strategy. Through injection of dsRNAs, the expression of the catalytic subunits of the oligosaccharyl transferase complex was efficiently silenced in nymphs of the notorious rice pest insect Nilaparvata lugens. Silencing of both STT3 isoforms resulted in a high mortality of the N. lugens nymphs. However, our data reveals the occurrence of a functional redundancy between the two isoforms when silencing only one of the isoforms. These observations confirm the potential to use the early genes in the N-glycosylation pathway as targets for an RNAi-based pest control strategy. In addition, the existence of a functional redundancy between the two STT3 isoforms presents a factor which one must take into account when designing RNAi-based approaches.


Assuntos
Hemípteros/genética , Controle de Insetos/métodos , Interferência de RNA , Animais , Hemípteros/crescimento & desenvolvimento , Ninfa/genética , Ninfa/crescimento & desenvolvimento
10.
PLoS Negl Trop Dis ; 13(4): e0006973, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30964873

RESUMO

A published study used a stochastic branching process to derive equations for the mean and variance of the probability of, and time to, extinction in population of tsetse flies (Glossina spp) as a function of adult and pupal mortality, and the probabilities that a female is inseminated by a fertile male. The original derivation was partially heuristic and provided no proofs for inductive results. We provide these proofs, together with a more compact way of reaching the same results. We also show that, while the published equations hold good for the case where tsetse produce male and female offspring in equal proportion, a different solution is required for the more general case where the probability (ß) that an offspring is female lies anywhere in the interval (0, 1). We confirm previous results obtained for the special case where ß = 0.5 and show that extinction probability is at a minimum for ß > 0.5 by an amount that increases with increasing adult female mortality. Sensitivity analysis showed that the extinction probability was affected most by changes in adult female mortality, followed by the rate of production of pupae. Because females only produce a single offspring approximately every 10 days, imposing a death rate of greater than about 3.5% per day will ensure the eradication of any tsetse population. These mortality levels can be achieved for some species using insecticide-treated targets or cattle-providing thereby a simple, effective and cost-effective method of controlling and eradicating tsetse, and also human and animal trypanosomiasis. Our results are of further interest in the modern situation where increases in temperature are seeing the real possibility that tsetse will go extinct in some areas, without the need for intervention, but have an increased chance of surviving in other areas where they were previously unsustainable due to low temperatures.


Assuntos
Controle de Insetos/métodos , Modelos Estatísticos , Moscas Tsé-Tsé/fisiologia , Animais , Feminino , Masculino , Densidade Demográfica , Probabilidade , Pupa/fisiologia
11.
J Insect Sci ; 19(2)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30822779

RESUMO

Exorista larvarum (L.), a polyphagous gregarious larval parasitoid of lepidopterans, can be mass produced both in vivo, using the greater wax moth Galleria mellonella (L.) (Lepidoptera: Pyralidae) as a factitious host, and in vitro, on artificial media composed of crude components. The present study was focused on another aspect of E. larvarum rearing, namely the influence of adult food on parasitoid performance. The standard food, consisting of lump sucrose and cotton balls soaked in a honey and water solution (1), was compared with other foods or food combinations, namely lump sucrose alone (2), honey and water solution (3), sucrose and water solution either alone (4) or combined with bee-collected pollen (5), and, finally, pollen alone (6). All foods were provided together with distilled water supplied in drinking troughs. Based on the parameters considered (i.e., female longevity, number of eggs laid on host larvae, puparia obtained from eggs, and adults emerged from puparia), pollen alone was deemed to be the most suitable food for adult females of E. larvarum. In particular, the pollen showed a longevity-promoting effect, increasing the number of eggs laid on host larvae throughout the female lifespan. The use of this adult food may also result in a higher flexibility of the management of E. larvarum colonies because it can be replaced weekly, as no desiccation or mold infections were ever found to occur.


Assuntos
Dípteros/fisiologia , Controle de Insetos/métodos , Mariposas/parasitologia , Controle Biológico de Vetores/métodos , Animais , Dieta , Dípteros/crescimento & desenvolvimento , Feminino , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/fisiologia , Longevidade , Mariposas/crescimento & desenvolvimento , Reprodução
12.
Proc Natl Acad Sci U S A ; 116(13): 6473-6481, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30833386

RESUMO

Bed bugs have reemerged in the United States and worldwide over recent decades, presenting a major challenge to both public health practitioners and housing authorities. A number of municipalities have proposed or initiated policies to stem the bed bug epidemic, but little guidance is available to evaluate them. One contentious policy is disclosure, whereby landlords are obligated to notify potential tenants of current or prior bed bug infestations. Aimed to protect tenants from leasing an infested rental unit, disclosure also creates a kind of quarantine, partially and temporarily removing infested units from the market. Here, we develop a mathematical model for the spread of bed bugs in a generalized rental market, calibrate it to parameters of bed bug dispersion and housing turnover, and use it to evaluate the costs and benefits of disclosure policies to landlords. We find disclosure to be an effective control policy to curb infestation prevalence. Over the short term (within 5 years), disclosure policies result in modest increases in cost to landlords, while over the long term, reductions of infestation prevalence lead, on average, to savings. These results are insensitive to different assumptions regarding the prevalence of infestation, rate of introduction of bed bugs from other municipalities, and the strength of the quarantine effect created by disclosure. Beyond its application to bed bugs, our model offers a framework to evaluate policies to curtail the spread of household pests and is appropriate for systems in which spillover effects result in highly nonlinear cost-benefit relationships.


Assuntos
Percevejos-de-Cama , Revelação , Controle de Insetos/métodos , Controle de Insetos/normas , Políticas , Animais , Percevejos-de-Cama/patogenicidade , Ectoparasitoses/epidemiologia , Ectoparasitoses/parasitologia , Características da Família , Habitação , Humanos , Renda , Controle de Insetos/economia , Modelos Teóricos , Prevalência , Quarentena , Sensibilidade e Especificidade
13.
BMC Biotechnol ; 19(1): 15, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30849970

RESUMO

BACKGROUND: Insect resistance in crops represents a main challenge for agriculture. Transgenic approaches based on proteins displaying insect resistance properties are widely used as efficient breeding strategies. To extend the spectrum of targeted pathogens and overtake the development of resistance, molecular evolution strategies have been used on genes encoding these proteins to generate thousands of variants with new or improved functions. The cotton boll weevil (Anthonomus grandis) is one of the major pests of cotton in the Americas. An α-amylase inhibitor (α-AIC3) variant previously developed via molecular evolution strategy showed inhibitory activity against A. grandis α-amylase (AGA). RESULTS: We produced in a few days considerable amounts of α-AIC3 using an optimised transient heterologous expression system in Nicotiana benthamiana. This high α-AIC3 accumulation allowed its structural and functional characterizations. We demonstrated via MALDI-TOF MS/MS technique that the protein was processed as expected. It could inhibit up to 100% of AGA biological activity whereas it did not act on α-amylase of two non-pathogenic insects. These data confirmed that N. benthamiana is a suitable and simple system for high-level production of biologically active α-AIC3. Based on other benefits such as economic, health and environmental that need to be considerate, our data suggested that α-AIC3 could be a very promising candidate for the production of transgenic crops resistant to cotton boll weevil without lethal effect on at least two non-pathogenic insects. CONCLUSIONS: We propose this expression system can be complementary to molecular evolution strategies to identify the most promising variants before starting long-lasting stable transgenic programs.


Assuntos
Inibidores Enzimáticos/metabolismo , Expressão Gênica , Engenharia Genética/métodos , Tabaco/genética , alfa-Amilases/antagonistas & inibidores , Animais , Evolução Molecular Direcionada , Inibidores Enzimáticos/química , Inativação Gênica , Controle de Insetos/métodos , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Gorgulhos , alfa-Amilases/genética , alfa-Amilases/metabolismo
14.
Environ Entomol ; 48(2): 434-443, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30850845

RESUMO

Melon thrips, Thrips palmi Karny (Thysanoptera: Thripidae), is a serious pest of vegetable, ornamental, and fruit crops. As a potential component of an integrated pest management (IPM) program, different plastic mulches including white-on-black, black-on-white, black-on-black, two metalized ultraviolet (UV)-reflective mulches, and a no mulch control were evaluated for managing T. palmi on six field-grown vegetable crops (eggplant, cucumber, squash, snap bean, Jalapeno pepper, and tomato) during the Fall of 2015 and 2016. Metalized reflective mulch significantly reduced the number of T. palmi in all vegetable crops compared with the other treatments. The highest numbers of T. palmi were observed on the white-on-black mulch and control treatments. The numbers of adults and larvae were highest on eggplant followed by cucumber, snap bean, squash, and Jalapeno pepper. The lowest numbers of T. palmi were observed on tomato plants. This study indicated that growing vegetable crops on metalized mulch is an effective method of reducing T. palmi populations in vegetable crops and should be considered in IPM programs for this insect species.


Assuntos
Agricultura/instrumentação , Produtos Agrícolas , Controle de Insetos/métodos , Tisanópteros , Animais , Larva , Densidade Demográfica
15.
J Insect Sci ; 19(2)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30817820

RESUMO

The rice moth, Corcyra cephalonica Stainton, an alternate host for the production of the parasitoid, Habrobracon hebetor Say, was reared on different diets, including pearl millet [Pennisetum glaucum (L.) R. Br.] (Poales: Poaceae) flour only, and in combinations of flours of sorghum [Sorghum bicolor (L.) Moench] (Poales: Poaceae), peanut (Arachis hypogea L.) (Fabales: Fabaceae), and cowpea [Vigna unguiculata (L.) Walp.] (Fabales: Fabaceae) to identify the optimal and economical proportion to be used under the conditions of Niger. The addition of cowpea or peanut to the pearl millet diet slightly increased C. cephalonica larval development time. Likewise, the addition of cowpea or peanut to cereal diets yielded a higher C. cephalonica larval survival. Female moths emerging from larvae fed on cereal and legume mixed diets produced higher eggs compared to the ones fed on sole and mixed cereals. Among legumes, cowpea addition is most interesting in terms of cost/production of C. cephalonica larvae. However, female moths emerging from larvae fed on different millet cowpea mix (5, 25, and 50%) laid significantly more eggs than those fed on sole pearl millet. Further, individual C. cephalonica larvae fed on 75% pearl millet + 25% cowpea produced significantly more H. hebetor. With an initial 25 C. cephalonica larvae kept for a 3-mo rearing period, the number of H. hebetor parasitoids produced will reach 2.68-10.07 million. In terms of cost/production ratio, the 75% pearl millet: 25% cowpea yielded better results.


Assuntos
Farinha/análise , Interações Hospedeiro-Parasita , Controle de Insetos/métodos , Mariposas/crescimento & desenvolvimento , Controle Biológico de Vetores/métodos , Vespas/crescimento & desenvolvimento , Animais , Produtos Agrícolas , Dieta , Feminino , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/fisiologia , Mariposas/parasitologia , Especificidade da Espécie , Vespas/fisiologia
16.
Parasit Vectors ; 12(1): 75, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30732628

RESUMO

BACKGROUND: There are many different traps available for studying fly populations. The aim of this study was to find the most suitable trap to collect synanthropic fly populations to assess the impact of increased latrine coverage in the state of Odisha, India. METHODS: Different baits were assessed for use in sticky pot traps (60% sucrose solution, 60 g dry sucrose, half a tomato and an non-baited control), followed by different colours of trap (blue versus yellow) and finally different types of trap (baited sticky pot trap versus sticky card traps). The experiments were undertaken in a semi-urban slum area of Bhubaneswar, the capital of Odisha. The first experiment was conducted in 16 households over 30 nights while experiments 2 and 3 were conducted in 5 households over 30 nights. RESULTS: The traps predominantly caught adult Musca domestica and M. sorbens (78.4, 62.6, 83.8% combined total in experiments 1-3 respectively). Non-baited traps did not catch more flies (median 7.0, interquartile range, IQR: 0.0-24.0) compared with baited traps (sucrose solution: 6.5, 1.0-27.0; dry sucrose: 5.0, 0.5-14.5; tomato: 5.0, 1.5-17.5). However, there were significantly more flies collected on blue sticky pot traps, which caught nearly three times as many flies as yellow sticky pot traps (Incidence Rate Ratio, IRR = 2.91; 95% CI: 1.77-4.79); P < 0.001). Sticky card traps (27, 8-58) collected significantly more flies than the non-baited sticky pot traps (10, 1.5-30.5). CONCLUSIONS: Blue sticky card traps can be recommended for the capture of synanthropic fly species as they are non-intrusive to residents, easy to use, readily allow for species identification, and collect sufficient quantities of flies over 12 hours for use in monitoring and control programmes.


Assuntos
Dípteros , Controle de Insetos/instrumentação , Controle de Insetos/métodos , Animais , Moscas Domésticas , Índia , Densidade Demográfica , Sacarose , Toaletes
17.
Environ Sci Pollut Res Int ; 26(11): 10708-10718, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30778939

RESUMO

The vine mealybug (VMB), Planococcus ficus (Hemiptera: Pseudococcidae), is a key insect pest of vineyards. While pheromone-based mating disruption (MD) has been successfully tested against a wide range of insect pests, knowledge about its efficacy against key mealybug species, such as P. ficus, is scarce. In this study, a novel MD product, Isonet® PF, was evaluated by testing 300, 400, and 500 dispensers/ha at four study sites located in Northern (Veneto) and Southern (Sicily) Italy. Experiments were carried out over 2 years by monitoring the mealybug populations in wine grape and table grape vineyards managed with and without the application of MD. Pheromone dispensers were periodically collected during the grapevine-growing season, extracted, and analyzed by GC-MS, to determine their pheromone content and the release in mg/ha/day. The results showed that use of the MD dispenser Isonet® PF reduced the percentage of VMB-infested bunches and the number of VMB specimens per bunch compared with the untreated controls. This was recorded over 2 years at all experimental sites. Differences in the incidence of infested bunches among the three tested rates of Isonet® PF were not detected. Overall, the results presented here contribute to optimizing the sex pheromone dosage used in MD control programs against VMB allowing a reduction of broad-spectrum insecticides currently employed to manage this important pest.


Assuntos
Hemípteros/fisiologia , Controle de Insetos/métodos , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Feminino , Hemípteros/efeitos dos fármacos , Masculino , Doenças das Plantas/parasitologia , Reprodução/efeitos dos fármacos , Estações do Ano , Sicília , Vitis/parasitologia
18.
Environ Entomol ; 48(2): 444-453, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30810746

RESUMO

Brown stink bug, Euschistus servus (Say), is a damaging pest of corn, Zea mays L. (Cyperales: Poaceae), in the southeastern United States. In North Carolina, during the spring, winter-planted wheat, Triticum aestivum L. (Cyperales: Poaceae), serves as the earliest available crop host, and E. servus seems to prefer this crop over seedling corn. In the absence of wheat in the agroecosystem, weeds serve as a bridge host for a portion of overwintered E. servus populations until they move to corn and other subsequent crops. Our objective was to reduce densities of E. servus in corn by manipulating the weedy field borders with mowing and applications of dicamba herbicide. During the study, multiple species of stink bugs (n =16) were found associated with weed plots. However, E. servus was the predominant (>94%) stink bug species in the corn. In this farmscape, density of E. servus adults in the unmanaged weed plots began declining around the second week of May, followed by an increase in density in adjacent corn plots. This movement coincided with the seedling growth of corn. In 2016, applications of dicamba in the weedy field border resulted in a lower density of E. servus in herbicide-treated weed plots compared with untreated plots. Despite this difference, manipulations of weeds did not lead to any significant changes in density of E. servus adults in corn. Further evidence suggested that a prominent external source of E. servus, other than field-bordering weeds, in the farmscape was likely driving densities in corn.


Assuntos
Heterópteros , Controle de Insetos/métodos , Plantas Daninhas , Animais , Densidade Demográfica , Dinâmica Populacional , Soja , Controle de Plantas Daninhas , Zea mays
19.
J Insect Sci ; 19(1)2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30772917

RESUMO

Pairs of electrocutor-grid ultraviolet light traps were assigned to three treatments to evaluate the effects of illumination events, e.g., light traps turned on, on house fly, Musca domestica L., attraction as indicated by numbers of flies captured by the traps. Both traps in treatment 1 were illuminated constantly (no illumination event). Both traps in treatment 2 were turned on, illuminated for 1 h, then turned off for 1 h, then repeated (1 illumination event every 2 h). Traps in treatment 3 were operated singularly. One trap was turned on for 1 h, then turned off. As it turned off, the other trap turned on for 1 h, then turned off, then repeated (1 illumination event every hour). The mean number of flies attracted per trap pair was significantly greater in treatment 1 than in treatments 2 or 3. However, in treatment 3, with one trap illuminated at a time and hourly illumination events, the mean fly catch was just 27% less, numerically, than the mean number of flies attracted to treatment 1 with both traps illuminated constantly. The effects of intermittent lighting and its potential use are discussed.


Assuntos
Moscas Domésticas/efeitos da radiação , Controle de Insetos/métodos , Fototaxia , Raios Ultravioleta , Animais , Florida
20.
Sci Total Environ ; 663: 632-643, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30731409

RESUMO

Agricultural land use has intended and unintended consequences for human livelihoods through feedbacks within coupled human and natural systems. In Senegal, West Africa, soils are a vital resource for livelihoods and food security in smallholder farming communities. In this study, we explored the connections among land use, soil conditions, plant nutrient content, and the abundance of several locust and grasshopper species. We worked in two rural farming villages in the Kaffrine region of Senegal. Oedaleus senegalensis was least abundant in groundnut areas where plant N was highest and abundance was negatively correlated with plant N across land use types. Overall, grasshoppers were most numerous in grazing and fallow areas. There was little variation in soil properties across land use types and soil organic matter (SOM) and inorganic soil N content were low throughout. SOM was positively correlated with soil inorganic N concentration, which in turn was positively correlated with plant N content. Of the management practices we surveyed, fallowing fields was important for soil N and SOM replenishment. These results corroborate other research indicating that land use, management practices, soil and plant nutrients, and insect herbivore abundance are mechanistically coupled. Although further research is needed, improving soil fertility could be used as an alternative to pesticides to keep locusts at bay and improve crop yields.


Assuntos
Proteção de Cultivos , Produtos Agrícolas/química , Gafanhotos/fisiologia , Controle de Insetos/métodos , Solo/química , Animais , Senegal
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