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1.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3615-3626, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621250

RESUMO

The visual communication between insect and plant is one of the key sensory signal channels for the survival, reproduction and defense of insects. The colored sticky boards, which are developed based on insects positive phototaxis and as one of the effective green pest control measures, have been widely applied for monitoring, forecasting and mass-trapping of many diurnal agricultural and forestry insect pests. In addition, they could be used to attract beneficial insects to the target areas to prey on or parasitize harmful insects, and to aid in pollination. Here, we discussed the insect phototaxis theory and the "attract and kill" mechanism of colored sticky boards and reviewed the effects of color, shape, size, height, density, facing direction, working duration of the sticky boards, as well as plant morphological characters and insect physiological status on trapping efficacy. We summarized various application techniques of the color sticky boards on different target pest insects in tea plantations, vegetable fields and greenhouses, etc. We analyzed various application technologies of combining colored sticky boards with synthetic sex pheromone attractants and/or botanical attractants and their efficacy; then evaluated the pros and cons of using the colored sticky boards for pest control or monitoring. Accordingly, we provided suggestions for improvements and discussed the trapping efficacy assessment and cost-benefit analysis. Finally, we proposed the RD directions of next generation colored sticky boards, especially its combination with synthetic pheromones/kairomones as an important integrated pest management (IPM) measure, and the future of the colored sticky board industry.


Assuntos
Fototaxia , Atrativos Sexuais , Animais , Controle de Insetos , Insetos , Feromônios
2.
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
3.
J Chem Ecol ; 45(8): 657-666, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31407199

RESUMO

The box tree moth, Cydalima perspectalis, is an invasive pest in Europe causing damage on Buxus species. In this study, we aimed to develop a "bisexual" lure to attract both female and male moths. Based on a previous screening bioassay we tested methyl salicylate, phenylacetaldehyde and eugenol as potential attractants in different combinations. The trapping results showed that both binary and ternary blends attracted male and female moths. Catches with these blends were comparable to catches with the synthetic pheromone. Subsequently we carried out single sensillum recordings, which proved the peripheral detection of the above-mentioned compounds on male and female antennae. To identify synergistic flower volatiles, which can be also attractive and can increase the trap capture, we collected flower headspace volatiles from 12 different flowering plant species. Several components of the floral scents evoked good responses from antennae of both females and males in gas chromatography-electroantennographic detection. The most active components were tentatively identified by gas chromatography coupled mass spectrometry as benzaldehyde, cis-ß-ocimene, (±)-linalool and phenethyl alcohol. These selected compounds in combination did not increase significantly the trap capture compared to the methyl salicylate- phenyacetaldehyde blend. Based on these results we discovered the first attractive blend, which was able to attract both adult male and female C. perspectalis in field conditions. These results will yield a good basis for the optimization and development of a practically usable bisexual lure against this invasive pest.


Assuntos
Comportamento Animal/efeitos dos fármacos , Mariposas/fisiologia , Feromônios/farmacologia , Animais , Eugenol/química , Eugenol/farmacologia , Feminino , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Controle de Insetos , Masculino , Monoterpenos/química , Monoterpenos/farmacologia , Feromônios/análise , Robinia/química , Robinia/metabolismo , Rosa/química , Rosa/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia
4.
J Insect Sci ; 19(4)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31313814

RESUMO

The past 100 yr have seen dramatic philosophical shifts in our approach to controlling or managing pest species. The introduction of integrated pest management in the 1970s resulted in the incorporation of biological and behavioral approaches to preserve ecosystems and reduce reliance on synthetic chemical pesticides. Increased understanding of the local ecosystem, including its structure and the biology of its species, can improve efficacy of integrated pest management strategies. Pest management strategies incorporating insect learning paradigms to control insect pests or to use insects to control other pests can mediate risk to nontarget insects, including pollinators. Although our understanding of insect learning is in its early stages, efforts to integrate insect learning into pest management strategies have been promising. Due to considerable differences in cognitive abilities among insect species, a case-by-case assessment is needed for each potential application of insect learning within a pest management strategy.


Assuntos
Controle de Insetos , Insetos , Aprendizagem , Animais
5.
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
6.
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
7.
Plant Dis ; 103(9): 2184-2190, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31287372

RESUMO

Little cherry disease (LCD) threatens the long-term economic sustainability of the Pacific Northwest sweet cherry (Prunus avium) industry. Results from a series of partial budget analyses indicate that additional investments in monitoring, testing, spraying to control for insect vectors, and removing infected trees are lower than the reduced profit losses compared with the do-nothing scenario. Also, management can prevent or lessen the negative impacts of higher little cherry virus (Velarivirus little cherry virus 1, Ampelovirus little cherry virus 2) spread rates. Our findings illustrate the importance of prevention, correct identification, and controlling for insect vectors in preventing the dissemination of LCD, for which the only known treatment is tree removal.


Assuntos
Agricultura , Closteroviridae , Doenças das Plantas , Prunus avium , Agricultura/métodos , Animais , Closteroviridae/fisiologia , Frutas , Controle de Insetos , Insetos Vetores/fisiologia , Doenças das Plantas/prevenção & controle , Prunus avium/virologia , Washington
8.
J Chem Ecol ; 45(8): 667-672, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313134

RESUMO

Agriotes ustulatus is an economically important click beetle in Europe. A female-produced pheromone, (E,E)-farnesyl acetate, has been identified and is used for monitoring and detecting males. More recently, a floral lure targeting females with modest, but significant, activity has been described. Based on preliminary data, we hypothesized, that similar to the effects on the congeneric A. brevis, addition of the pheromone to the floral lure should improve female A. ustulatus catches. Also, as click beetles have been reported to respond to white light, we studied possible interactions between visual and chemical cues. In field trials, the addition of the synthetic pheromone to the floral lure resulted in a dramatic increase in the number of females trapped, whereas male catches remained unaffected and equal to those in traps baited with pheromone only. A white visual cue did not influence trap catches. Maximum catches of both sexes of A. ustulatus can be achieved using the pheromone and the floral lure inside the same trap. Furthermore, the compounds can be formulated in a single polyethylene bag dispenser, making handling of the trap easier. Due to a much larger proportion of females in the catch, this improved trap may be a promising tool for semiochemical-based, environmentally sound agricultural practice against this important pest.


Assuntos
Besouros/fisiologia , Feromônios/química , Acroleína/análogos & derivados , Acroleína/química , Acroleína/farmacologia , Animais , Anisóis/química , Anisóis/farmacologia , Comportamento Animal/efeitos dos fármacos , Farneseno Álcool/análogos & derivados , Farneseno Álcool/química , Farneseno Álcool/farmacologia , Feminino , Flores/química , Flores/metabolismo , Controle de Insetos , Masculino , Feromônios/farmacologia , Estereoisomerismo
9.
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
10.
J Insect Sci ; 19(2)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31222326

RESUMO

Hemlock woolly adelgid, Adelges tsugae (Annand) (Hemiptera: Adelgidae), has caused significant damage to both eastern [Tsuga canadensis (L.) Carrière] and Carolina hemlock (Tsuga caroliniana Englemann) (Pinales: Pinaceae) since it was first reported in the eastern United States. This adelgid is particularly damaging to these hemlock species due to a lack of co-evolved plant defenses and natural enemies able to suppress hemlock woolly adelgid populations. Management of hemlock woolly adelgid relies heavily on insecticides to prevent death of vulnerable trees. Biological control programs have released natural enemies of hemlock woolly adelgid to aid in control at the landscape level. Quarantine restrictions on hemlock are in place in some regions of the United States and Canada. These quarantines impact sales and shipment of hemlock trees from nurseries as well as other hemlock products. A review of insect biology, description of life stages, damage, management options, and quarantine restrictions for hemlock woolly adelgid is presented.


Assuntos
Hemípteros , Controle de Insetos , Animais , Ecossistema , Quarentena , Tsuga
11.
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
12.
Onderstepoort J Vet Res ; 86(1): e1-e6, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31170783

RESUMO

African animal trypanosomosis (AAT) is caused by several species of the genus Trypanosoma, a parasitic protozoan infecting domestic and wild animals. One of the major effects of infection with pathogenic trypanosome is anaemia. Currently, the control policies for tsetse and trypanosomosis are less effective in South Africa. The only response was to block treat all infected herds and change the dip chemical to one which controls tsetse flies during severe outbreaks. This policy proved to be less effective as demonstrated by the current high level of trypanosome infections in cattle. Our objective was to study the impacts of AAT (nagana) on animal productivity by monitoring the health of cattle herds kept in tsetse and trypanosomosis endemic areas before and after an intervention that reduces the incidence of the disease. The study was conducted on a farm in northern KwaZulu-Natal which kept a commercial cattle herd. There was no history of any cattle treatment for trypanosome. All cattle were generally in poor health condition at the start of the study though the herd received regular anthelminthic treatment. A treatment strategy using two drugs, homidium bromide (ethidium) and homidium chloride (novidium), was implemented. Cattle were monitored regularly for 13 months for herd trypanosomosis prevalence (HP), herd average packed cell volume (H-PCV) and the percentage of the herd that was anaemic (HA). A total of six odour-baited H-traps were deployed where cattle grazed from January 2006 to August 2007 to monitor the tsetse population. Glossina brevipalpis Newstead and Glossina austeni Newstead were collected continuously for the entire study period. High trypanosomes HP (44%), low average H-PCV (29.5) and HA (24%) were rerecorded in the baseline survey. All cattle in the herd received their first treatment with ethidium bromide. Regular monthly sampling of cattle for the next 142 days showed a decline in HP of 2.2% - 2.8%. However, an HP of 20% was recorded by day 220 and the herd received the second treatment using novidium chloride. The HP dropped to 0.0% and HA to 0.0% by day 116 after the second treatment. The cow group was treated again by day 160 when the HP and HA were 27.3% and 11%, respectively. The same strategy was applied to the other two groups of weaners and the calves at the time when their HP reached 20%. Ethidium and novidium treatment protected cattle, that were under continuous tsetse and trypanosomosis challenge, for up to 6 months. Two to three treatments per year may be sufficient for extended protection. However, this strategy would need to be included into an integrated pest management approach combining vector control for it to be sustainable.


Assuntos
Criação de Animais Domésticos , Anti-Helmínticos/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Controle de Insetos , Tripanossomíase Africana/veterinária , Animais , Anti-Helmínticos/administração & dosagem , Bovinos , Doenças dos Bovinos/epidemiologia , Esquema de Medicação/veterinária , Fazendas , Insetos Vetores , África do Sul/epidemiologia , Resultado do Tratamento , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Bovina/tratamento farmacológico , Moscas Tsé-Tsé
13.
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
14.
Adv Exp Med Biol ; 1142: 273-292, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31102251

RESUMO

Chitinous structures are physiologically fundamental in insects. They form the insect exoskeleton, play important roles in physiological systems and provide physical, chemical and biological protections in insects. As critically important structures in insects, chitinous structures are attractive target sites for the development of new insect-pest-control strategies. Chitinous structures in insects are complex and their formation and maintenance are dynamically regulated with the growth and development of insects. In the past few decades, studies on insect chitinous structures have shed lights on the physiological functions, compositions, structural formation, and regulation of the chitinous structures. Current understanding of the chitinous structures has indicated opportunities for exploring new target sites for insect control. Mechanisms to disrupt chitinous structures in insects have been studied and strategies for the potential development of new means of insect control by targeting chitinous structures have been proposed and are practically to be explored.


Assuntos
Quitina , Controle de Insetos , Animais , Insetos
15.
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
16.
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
17.
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
18.
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
20.
Parasit Vectors ; 12(1): 184, 2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31029147

RESUMO

BACKGROUND: The social determinants of health (SDHs) condition disease distribution and the ways they are handled. Socio-economic inequalities are closely linked to the occurrence of neglected tropical diseases, but empirical support is limited in the case of Chagas disease, caused by the protozoan Trypanosoma cruzi. Herein we assessed the relationship between key structural SDHs and the risk of T. cruzi vector-borne transmission in rural communities of the Argentine Chaco occupied by creoles and an indigenous group (Qom). We used multiple correspondence analysis to quantify the household-level socio-economic position (social vulnerability and assets indices), access to health and sanitation services, and domestic host availability. We identified the most vulnerable population subgroups by comparing their demographic profiles, mobility patterns and distribution of these summary indices, then assessed their spatial correlation and household-level effects on vector domiciliary indices as transmission risk surrogates. RESULTS: Qom households had higher social vulnerability and fewer assets than creoles, as did local movers and migrant households compared with non-movers. We found significantly positive effects of social vulnerability and domestic host availability on infected Triatoma infestans abundance, after adjusting for ethnicity. Access to health and sanitation services had no effect on transmission risk. Only social vulnerability displayed significant global spatial autocorrelation up to 1 km. A hotspot of infected vectors overlapped with an aggregation of most vulnerable households. CONCLUSIONS: This synthetic approach to assess socio-economic related inequalities in transmission risk provides key information to guide targeted vector control actions, case detection and treatment of Chagas disease, towards sustainability of interventions and greater reduction of health inequalities.


Assuntos
Doença de Chagas/transmissão , Grupos Populacionais , Determinantes Sociais da Saúde/etnologia , Fatores Socioeconômicos , Adolescente , Adulto , Idoso , Animais , Argentina , Doença de Chagas/etnologia , Criança , Pré-Escolar , Características da Família , Feminino , Humanos , Controle de Insetos , Insetos Vetores/parasitologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , População Rural , Inquéritos e Questionários , Triatoma/parasitologia , Trypanosoma cruzi , Adulto Jovem
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