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1.
J Insect Sci ; 20(2)2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32112650

RESUMO

Nine strains of five species of entomopathogenic hypocrealean fungi were tested against adults of the Asian longhorned beetle, Anoplophora glabripennis (Motschulsky). These strains have been developed as commercial biopesticide products in the United States, Brazil, South Korea, or the European Union (EU). Metarhizium anisopliae (Metschnikoff) (Hypocreales: Clavicipitaceae) ESALQ E-9 and Metarhizium brunneum (Petch) F52 (formerly M. anisopliae F52) (Hypocreales: Clavicipitaceae) killed 100% of treated beetles with the shortest survival times. Virulence differed among the five strains of Beauveria bassiana (Balsamo) (Hypocreales: Cordycipitaceae) tested, ranging from 0 to 77.3% mortality within 28 d. Two Isaria fumosorosea (Wize, 1904) (Hypocreales: Cordycipitaceae) (formerly Paecilomyces fumosoroseus) strains and the Lecanicillium muscarium (Petch) Zare & Gams (Hypocreales: Cordycipitaceae) strain used in Mycotal were not pathogenic to A. glabripennis adults. Within the entomopathogenic fungi tested, the Metarhizium strains may be the most appropriate for further evaluation.


Assuntos
Beauveria/patogenicidade , Besouros/microbiologia , Metarhizium/patogenicidade , Controle Biológico de Vetores/métodos , Animais , Hypocreales/patogenicidade , Virulência
2.
J Agric Food Chem ; 68(8): 2539-2546, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32023056

RESUMO

The rice planthopper is a very important hemipteran pest that preys on rice and substantially affects the safety of rice production. Moreover, the long-term prevention and control of these pests with chemical pesticides has led to an increase in the resistance of the rice planthopper as well as serious environmental pollution and food safety problems. Bacillus thuringiensis (Bt) has been used for the efficient and green control of a variety of rice pests. Therefore, based on the high-throughput screening of Bt strains that are active against the rice planthopper, we found that Bt strain B4F11 showed certain insecticidal activity against Laodelphax striatellus Fallén, and we have identified a novel insecticidal protein Cry78Ba1 from the Bt strain B4F11, which is expected to provide the specific and safe control of the rice planthopper. The Cry78Ba1 protein is composed of 380 amino acid residues with a molecular weight of 42.55 kDa and contains conserved Ricin_B_Lectin and Toxin_10 superfamily domains. It displays high insecticidal activity against L. striatellus with a lethal concentration (LC50) of 9.723 µg/mL. More importantly, this Toxin_10-like protein does not display sequence homology to any known allergen and can be degraded and inactivated rapidly when heated at 90 °C and in simulated gastrointestinal fluid. In summary, Cry78Ba1 has great potential for applications in the efficient and safe prevention and control of the rice planthopper.


Assuntos
Bacillus thuringiensis/genética , Proteínas de Bactérias/toxicidade , Endotoxinas/toxicidade , Hemípteros/efeitos dos fármacos , Proteínas Hemolisinas/toxicidade , Inseticidas/toxicidade , Animais , Bacillus thuringiensis/química , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Endotoxinas/genética , Endotoxinas/metabolismo , Hemípteros/fisiologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Inseticidas/metabolismo , Oryza/parasitologia , Controle Biológico de Vetores/métodos , Doenças das Plantas/parasitologia
3.
J Insect Sci ; 20(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32104893

RESUMO

Different densities prerelease packing and times of lethargy in the fruit fly parasitoids Diachasmimorpha longicaudata (Ashmead) were evaluated in order to standardize the process of chilled insect technique for this species. Adults were kept at densities of 0.048, 0.072, 0.096, 0.120, and 0.144 parasitoids/cm2 before release in a México tower, where thermal lethargy was induced at a temperature of 2 ± 2°C for 45 min. Samples of parasitoids were collected to evaluate mortality, survival, fecundity, and flight capacity. All densities showed a similar mortality, both for males (ca. >10%) and females (ca. <7). There was no effect of density on survival and flight capacity in both sexes. On the other hand, fecundity increased with density, 1.66 sons/♀/day, similar to the control. We conclude that a density of 30,000 pupae per cage (0.144 parasitoids/cm2) is adequate for the massive prerelease packaging of the parasitoid D. longicaudata. Regarding the thermal lethargy period, 180 min under 2 ± 2°C conditions, considered as time for management, does not affect the survival, fecundity, and flight capacity of adults. The results obtained are of great utility to establish prerelease packaging parameters for D. longicaudata used in the biological control of Tephritidae fruit fly populations.


Assuntos
Temperatura Baixa , Controle Biológico de Vetores/métodos , Vespas/fisiologia , Animais , Feminino , Fertilidade/fisiologia , Voo Animal/fisiologia , Masculino , Tephritidae/parasitologia
5.
Ecotoxicology ; 29(2): 148-155, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31927677

RESUMO

Stratiolaelaps scimitus (Womersley) and Cosmolaelaps brevistilis (Karg) (Acari: Laelapidae) are predatory mites of soil-inhabiting pests, mainly small insects. Fungus gnats fly species are found in greenhouse strawberry production and may be controlled with predatory mites, being important to know their compatibility with the pesticides used in strawberry crops. In this study, the compatibility of seven commercial pesticides used in strawberry cultivation with the predatory mites S. scimitus and C. brevistilis was assessed in laboratory conditions. Survival and oviposition rates were evaluated between 0.5 and 120 h after treatment (HAT). The results demonstrate that lambda-cyhalothrin treatment resulted in the lowest survival rate for both mites in the first evaluations, being moderately harmful, while spinetoran was slightly harmful to C. brevistilis. On the other hand, abamectin, azadirachtin, azoxystrobin + difenoconazole, iprodione and thiamethoxam were harmless for both mites and, oviposition rate was significantly different only at 72 and 120 HAT for S. scimitus and C. brevistilis respectively. These results may be used to develop guidelines for the adoption of selective pesticides in integrated pest management programs that conserves predatory mites.


Assuntos
Fragaria/fisiologia , Ácaros/fisiologia , Controle Biológico de Vetores/métodos , Praguicidas , Animais , Comportamento Predatório/efeitos dos fármacos
6.
Exp Parasitol ; 208: 107812, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31809704

RESUMO

The bovine tick, Rhipicephalus microplus, is the main ectoparasite of cattle and causes loss of billions of dollars worldwide in lost meat, milk, and leather production, as well as control expenses. In addition to systemically impacting the host during the parasitic act, this parasite is also an important disease vector. Traditionally, the main commercial control of the tick is achieved through application of chemical acaricides, which can leave residues in the meat and milk. Moreover, ticks can become resistant to these chemicals due to their massive and incorrect use. Many alternative methods have been tested including vaccines and natural products from plant origin. However, the efficacy of these treatments is variable and limited, especially when used alone. Arthropod-pathogenic fungi, such as Metarhizium anisopliae, are among the natural microbial agents with promising potential to be used alone or in association with other products, for example with chemical acaricides. This article discusses several aspects of bovine tick control related to the use of M. anisopliae, which is one of the most studied and viable alternative tools for effective tick control.


Assuntos
Doenças dos Bovinos/prevenção & controle , Metarhizium/fisiologia , Controle Biológico de Vetores/métodos , Rhipicephalus , Infestações por Carrapato/veterinária , Animais , Bovinos , Doenças dos Bovinos/economia , Doenças dos Bovinos/parasitologia , Controle Biológico de Vetores/normas , Rhipicephalus/microbiologia , Rhipicephalus/fisiologia , Infestações por Carrapato/economia , Infestações por Carrapato/parasitologia , Infestações por Carrapato/prevenção & controle
7.
Arch Insect Biochem Physiol ; 103(3): e21645, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31742774

RESUMO

In insect reverse genetics, dietary delivery of interfering RNAs is a practical approach in nonmodel species, such as thrips, whose small size, and feeding behavior restricts the use of other delivery methods. In a laboratory context, an unsuitable diet could confound the interpretation of an RNA interference (RNAi) phenotype, however well-formulated artificial diets can minimize experimental variability, reduce the need for insect handling, and can further be used for roles, such as delivering double-strand RNA (dsRNA)-expressing recombinant bacteria. In this study, artificial diets for oral delivery of dsRNA were developed for two important pest thrips species, western flower thrips (Frankliniella occidentalis) and onion thrips (Thrips tabaci), with the goal of (a) stimulating feeding behavior, (b) supporting optimal growth rates of dsRNA-expressing symbiotic bacteria, and (c) nutritionally supporting the thrips for sufficient periods to observe RNAi phenotypes. The efficacy of artificial diets for ingesting "naked" dsRNA or dsRNA-expressing symbionts and dsRNA delivery via host plant uptake was evaluated. Compared with previously published diet formulations, new combinations based on tryptone, yeast, and soy were superior for enhancing feeding and longevity. However, simply adding "naked" dsRNA to an artificial diet was an unreliable form of RNAi delivery in our hands due to dsRNA degradation. Delivery via host plants was more successful, and the new diet formulation was suitable for symbiont-mediated dsRNA delivery, which we believe is the most convenient approach for large-scale knockdown experiments. This study, therefore, provides alternative methodologies for thrips rearing, dietary RNAi delivery, and insights into the challenges of performing dietary RNAi in nonmodel insects.


Assuntos
Comportamento Alimentar , Controle de Insetos/métodos , Controle Biológico de Vetores/métodos , Interferência de RNA , Tisanópteros , Animais , Bactérias , Insetos Vetores , RNA de Cadeia Dupla
8.
Insect Mol Biol ; 29(1): 1-8, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31194893

RESUMO

Culex quinquefasciatus is an important mosquito vector of a number of viral and protozoan pathogens of humans and animals, and naturally carries the endosymbiont Wolbachia pipientis, strain wPip. Wolbachia are used in two distinct vector control strategies: firstly, population suppression caused by mating incompatibilities between mass-released transinfected males and wild females; and secondly, the spread of pathogen transmission-blocking strains through populations. Using embryonic microinjection, two novel Wolbachia transinfections were generated in C. quinquefasciatus using strains native to the mosquito Aedes albopictus: a wAlbB single infection, and a wPip plus wAlbA superinfection. The wAlbB infection showed full bidirectional cytoplasmic incompatibility (CI) with wild-type C. quinquefasciatus in reciprocal crosses. The wPipwAlbA superinfection showed complete unidirectional CI, and therefore population invasion potential. Whereas the wAlbB strain showed comparatively low overall densities, similar to the native wPip, the wPipwAlbA superinfection reached over 400-fold higher densities in the salivary glands compared to the native wPip, suggesting it may be a candidate for pathogen transmission blocking.


Assuntos
Culex/microbiologia , Wolbachia/fisiologia , Aedes/microbiologia , Animais , Feminino , Masculino , Controle de Mosquitos/métodos , Mosquitos Vetores/microbiologia , Controle Biológico de Vetores/métodos , Glândulas Salivares/microbiologia , Simbiose , Wolbachia/classificação
9.
Microbiol Res ; 230: 126347, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31586859

RESUMO

Biocontrol has emerged in recent years as an alternative to pesticides. Given the importance of environmental preservation using biocontrol, in this study two antagonistic bacteria against phytopathogenic fungi were isolated and evaluated. These bacterial strains, identified as Paenibacillus polymyxa NMA1017 and Burkholderia cenocepacia CACua-24, inhibited (70 to 80%) the development of two phytopathogens of economic importance: the fungus Rhizoctonia solani RhCh-14, isolated from chili pepper, and the oomycete Pythium ultimum PyFr-14, isolated from tomato. The spectrum was not limited to the previous pathogens, but also to other phytopathogenic fungus, some bacteria and other oomycetes. Fungi-bacteria microcultures observed with optical and scanning electron microscopy revealed hyphae disintegration and pores formation. The antifungal activity was found also in the supernatant, suggesting a diffusible compound is present. Innocuous tests on tobacco leaves, blood agar, bean seed germination and in Galleria mellonella larvae showed that strain NMA1017 has the potential to be a biocontrol agent. Greenhouse experiments with bean plants inoculated with P. polymyxa exhibited the efficacy to inhibit the growth of R. solani and P. ultimum. Furthermore, P. polymyxa NMA1017 showed plant growth promotion activities, such as siderophore synthesis and nitrogen fixation which can contribute to the crop development.


Assuntos
Antifúngicos/farmacologia , Burkholderia cenocepacia/química , Paenibacillus polymyxa/química , Controle Biológico de Vetores/métodos , Doenças das Plantas/microbiologia , Pythium/efeitos dos fármacos , Rhizoctonia/efeitos dos fármacos , Antifúngicos/metabolismo , Burkholderia cenocepacia/metabolismo , Paenibacillus polymyxa/metabolismo , Pythium/crescimento & desenvolvimento , Pythium/fisiologia , Rhizoctonia/crescimento & desenvolvimento , Rhizoctonia/fisiologia , Tabaco/crescimento & desenvolvimento , Tabaco/microbiologia
10.
Arch Insect Biochem Physiol ; 103(3): e21652, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31845410

RESUMO

Agricultural pest control using genetic-based methods provides a species-specific and environmentally harmless way for population suppression of fruit flies. One way to improve the efficiency of such methods is through self-limiting, female-eliminating approaches that can alter an insect populations' sex ratio toward males. In this microreview, we summarize recent advances in synthetic sex ratio distorters based on X-chromosome shredding that can induce male-biased progeny. We outline the basic principles to guide the efficient design of an X-shredding system in an XY heterogametic fruit fly species of interest using CRISPR/Cas gene editing, newly developed computational tools, and insect genetic engineering. We also discuss technical aspects and challenges associated with the efficient transferability of this technology in fruit fly pest populations, toward the potential use of this new class of genetic control approaches for pest management purposes.


Assuntos
Sistemas CRISPR-Cas , Dípteros/genética , Controle de Insetos/métodos , Controle Biológico de Vetores/métodos , Razão de Masculinidade , Animais , Feminino , Edição de Genes , Masculino
11.
An Acad Bras Cienc ; 91(4): e20181001, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800699

RESUMO

Laboratory trials were performed to determine the impact of three Neotropical predatory coccinellids (Cycloneda sanguinea, Eriopis connexa and Coleomegilla quadrifasciata) and a minute pirate bug (Orius insidiosus) on Chaetosiphon fragaefolii, an important strawberry aphid pest. The predation on C. fragaefolii nymphs and adults, as well as the time to the first attack of all predators were compared with predation on Aphis gossypii. Predator preferences for prey and aphid defensive behavior were also evaluated. Moreover, the effect of coccinellids on C. fragaefolii population growth was assessed in experimental greenhouse conditions. The predation rate varied among predators, being significantly lower for O. insidiosus than for the coccinellids. Consumption was higher on A. gossypii than on C. fragaefolii, regardless of the aphids developmental stage. The time to the first attack of all predators was longer in the presence of C. fragaefolii. Walking away and cornicle secretion were the most common antipredator behaviors of aphid against coccinellids and O. insidiosus, respectively. Coccinellids preferred A. gossypii over C. fragaefolii, while O. insidiosus showed indifference. Cycloneda sanguinea and E. connexa exhibited the highest suppression effect on the growth rate of C. fragaefolii. Thus, the four predators evaluated could contribute to reduce strawberry aphid populations, especially C. sanguinea and E. connexa.


Assuntos
Afídeos , Besouros/fisiologia , Controle Biológico de Vetores/métodos , Comportamento Predatório/fisiologia , Animais , Besouros/classificação , Fragaria/parasitologia , Fatores de Tempo
12.
Nat Biotechnol ; 37(12): 1513-1520, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31792408

RESUMO

Bacteriophages have been proposed as an alternative to pesticides to kill bacterial pathogens of crops. However, the efficacy of phage biocontrol is variable and poorly understood in natural rhizosphere microbiomes. We studied biocontrol efficacy of different phage combinations on Ralstonia solanacearum infection in tomato. Increasing the number of phages in combinations decreased the incidence of disease by up to 80% in greenhouse and field experiments during a single crop season. The decreased incidence of disease was explained by a reduction in pathogen density and the selection for phage-resistant but slow-growing pathogen strains, together with enrichment for bacterial species that were antagonistic toward R. solanacearum. Phage treatment did not affect the existing rhizosphere microbiota. Specific phage combinations have potential as precision tools to control plant pathogenic bacteria.


Assuntos
Bacteriófagos/genética , Lycopersicon esculentum/microbiologia , Controle Biológico de Vetores/métodos , Doenças das Plantas/microbiologia , Ralstonia solanacearum , Ralstonia solanacearum/genética , Ralstonia solanacearum/patogenicidade , Ralstonia solanacearum/virologia , Rizosfera
13.
Arch Insect Biochem Physiol ; 102(3): e21593, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31612553

RESUMO

The diamondback moth, Plutella xylostella, is one of the most destructive pests worldwide and its management relies exclusively on frequent application of chemical insecticides. Resistance to common insecticides is now widespread, and novel classes of insecticides are needed. Entomopathogenic bacteria and their related products play an important role in the management of this pest. In the present work, one bacterial strain was separated from infected pupae of P. xylostella collected from field and its pathogenicity was evaluated. On the basis of the 16S ribosomal RNA sequencing, BLASTN, and phylogenetic analysis, this bacterial isolate was identified as Pseudomonas cedrina. Oral administration of P. cedrina at levels above 10,000 CFU/ml gave significant mortality to P. xylostella larvae. The pathogenicity was also observed by reduced longevity and fecundity in adult females. However, when live bacterial cells were removed, the cultured broth lost any pathogenicity. In response to the bacterial infection, P. xylostella expressed antimicrobial and stress-associated genes. A mixture treatment of P. cedrina and Bacillus thuringiensis showed an additive effect on larval mortality of P. xylostella. These results indicated that P. cedrina is an opportunistic entomopathogen without secretion of toxins. Furthermore, the additive effect of P. cedrina and B. thuringiensis provide a new insight to develop new strategy for controlling P. xylostella.


Assuntos
Mariposas/microbiologia , Pseudomonas/isolamento & purificação , Animais , Feminino , Fertilidade , Perfilação da Expressão Gênica , Larva/microbiologia , Longevidade , Mariposas/genética , Mariposas/metabolismo , Controle Biológico de Vetores/métodos , Filogenia , Pseudomonas/classificação , Pseudomonas/patogenicidade , Pupa/microbiologia , RNA Ribossômico 16S
15.
Parasit Vectors ; 12(1): 483, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615544

RESUMO

BACKGROUND: Biting midges of the genus Culicoides vector multiple veterinary pathogens and are difficult to control. Endosymbionts particularly Wolbachia pipientis may offer an alternative to control populations of Culicoides and/or impact disease transmission in the form of population suppression or replacement strategies. METHODS: Culicoides sonorensis cell lines were transfected with a Wolbachia infection using a modified shell vial technique. Infections were confirmed using PCR and cell localization using fluorescent in situ hybridization (FISH). The stability of Wolbachia infections and density was determined by qPCR. qPCR was also used to examine immune genes in the IMD, Toll and JACK/STAT pathways to determine if Wolbachia were associated with an immune response in infected cells. RESULTS: Here we have transfected two Culicoides sonorensis cell lines (W3 and W8) with a Wolbachia infection (walbB) from donor Aedes albopictus Aa23 cells. PCR and FISH showed the presence of Wolbachia infections in both C. sonorensis cell lines. Infection densities were higher in the W8 cell lines when compared to W3. In stably infected cells, genes in the immune Toll, IMD and JAK/STAT pathways were upregulated, along with Attacin and an Attacin-like anti-microbial peptides. CONCLUSIONS: The successful introduction of Wolbachia infections in C. sonorensis cell lines and the upregulation of immune genes, suggest the utility of using Wolbachia for a population replacement and/or population suppression approach to limit the transmission of C. sonorensis vectored diseases. Results support the further investigation of Wolbachia induced pathogen inhibitory effects in Wolbachia-infected C. sonorensis cell lines and the introduction of Wolbachia into C. sonorensis adults via embryonic microinjection to examine for reproductive phenotypes and host fitness effects of a novel Wolbachia infection.


Assuntos
Ceratopogonidae/microbiologia , Insetos Vetores/microbiologia , Transfecção/métodos , Wolbachia/patogenicidade , Aedes/citologia , Animais , Agentes de Controle Biológico , Linhagem Celular/microbiologia , Ceratopogonidae/imunologia , Imunidade/genética , Hibridização in Situ Fluorescente , Insetos Vetores/imunologia , Controle Biológico de Vetores/métodos , Fenótipo , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase em Tempo Real , Reprodução , Wolbachia/genética , Wolbachia/imunologia
16.
An Acad Bras Cienc ; 91(3): e20180597, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618410

RESUMO

Several parasitoids attacking the same host may lead to competition. Adult parasitoids' abilities to find, parasitize and defend hosts determine resource's retention potential. In soybean, two egg parasitoid species, Telenomus podisi and Trissolcus urichi (Hymenoptera: Platygastridae), compete on the egg masses of Piezodorus guildinii (Hemiptera: Pentatomidae) one of the major pest of this crop. We evaluated parasitoid's abilities to exploit hosts' footprints; and parasitoid's behavior when competing for the same host. Both arena residence time and retention time were similar for T. podisi and T. urichi on male or female host footprints. In its turn, T. urichi reentered the area contaminated with P. guildinii more times and staid longer in it than T. podisi. Furthermore, when competing for the same egg mass, each parasitoid species won (was in possession of the host by the end of the experiment) half of the replicates, and the number of times each wasp species contacted host in the first place was similar, without affecting replicate outcome (who ultimately won). Both species started agonistic and non-agonistic encounters. This study provides information about the potential interspecific competition between these parasitoids, which contributes to evaluate the compatibility of multiple natural enemies' biological control programs for stink bugs.


Assuntos
Hemípteros/parasitologia , Controle Biológico de Vetores/métodos , Animais , Comportamento Animal/fisiologia , Feminino , Hemípteros/fisiologia , Interações Hospedeiro-Parasita , Masculino , Oviposição , Óvulo/fisiologia , Soja , Vespas/parasitologia
17.
BMC Genomics ; 20(1): 751, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623553

RESUMO

BACKGROUND: Massive techniques have been evaluated for developing different pest control methods to minimize fertilizer and pesticide inputs. As "push-pull" strategy utilizes generally non-toxic chemicals to manipulate behaviors of insects, such strategy is considered to be environmentally friendly. "Push-pull" strategy has been extraordinarily effective in controlling stem borers, and the identification of new "pushing" or "pull" components against stem borers could be significantly helpful. RESULTS: In this study, the results of field trapping assay and behavioral assay showed the larvae of C.auricilius, one kind of stem borers, could be deterred by rice plant under tilling stage, its main host crop. The profiles of volatiles were compared between rice plants under two different developmental stages, and α-pinene was identified as a key differential component. The repelling activity of α-pinene against C.auricilius was confirmed by Y-tube olfactometer. For illuminating the olfactory recognition mechanism, transcriptome analysis was carried out, and 13 chemosensory proteins (CSPs) were identified in larvae and 19 CSPs were identified in adult of C.auriciliu, which was reported for the first time in this insect. Among these identified CSPs, 4 CSPs were significantly regulated by α-pinene treatment, and CSP8 showed good binding affinity with α-pinene in vitro. CONCLUSIONS: Overall, C.auricilius could be repelled by rice plant at tilling stage, and our results highlighted α-pinene as a key component in inducing repelling activity at this specific stage and confirmed the roles of some candidate chemosensory elements in this chemo-sensing process. The results in this study could provide valuable information for chemosensory mechanism of C.auricilius and for identification of "push" agent against rice stem borers.


Assuntos
Repelentes de Insetos/metabolismo , Mariposas/fisiologia , Controle Biológico de Vetores/métodos , Doenças das Plantas/prevenção & controle , Compostos Orgânicos Voláteis/metabolismo , Animais , Quimiotaxia/genética , Quimiotaxia/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Larva/genética , Larva/fisiologia , Mariposas/classificação , Mariposas/genética , Oryza/química , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/parasitologia , Doenças das Plantas/parasitologia , Proteínas de Plantas/genética , Ligação Proteica
18.
J Insect Sci ; 19(5)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31612947

RESUMO

Invasive insect species can act as a plague across the globe, capable of vast expansion and rapid, proliferate reproduction. The spread of pathogens of serious diseases such as malaria and Zika virus and damages to agricultural crops number some of the afflictions invasive insects provide to humans alone. Additionally, an escape from predators can fail to keep invasive insects in check, providing potential threats such as extra resource competition to native species when insects invade. A variety of methods are employed to combat these invasive species, each with their own varying levels of success. Here, we explore the more traditional methods of invasive insect pest control, such as pesticides and biological control. In lieu of several unintended consequences resulting from such practices, we suggest some should be abandoned. We evaluate the potential of new techniques, in particular, those with a genetic component, regarding the costs, benefits and possible consequences of implementing them. And finally, we consider which techniques should be the focus of future research, if we truly wish to manage or even eradicate invasive insects in their introduced lands.


Assuntos
Controle de Insetos/métodos , Insetos , Inseticidas/administração & dosagem , Controle Biológico de Vetores/métodos , Animais , Controle de Insetos/instrumentação , Controle Biológico de Vetores/instrumentação
19.
Biol Res ; 52(1): 51, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31530279

RESUMO

BACKGROUND: The leafcutter ant (Atta cephalotes) is associated with losses in the agricultural sector, due to its defoliating activity; for its control, biological, mechanical and chemical methods have been developed, the latter associated with adverse effects on human and environmental health. This research validated in the field for the control of the leafcutter ant (A. cephalotes) using a mixture of Beauveria bassiana and Trichoderma lignorum spores. METHODS: The effectiveness from the combination of spores of B. bassiana and T. lignorum with an initial concentration of 2 × 109 spores/ml, in the following proportions of B. bassiana and T. lignorum, A (1:1), of each fungus. It was evaluated within the university campus, comparing it with two commercial formulations, Mycotrol (B. bassiana) and Mycobac (T. lignorum). Additionally, this formulation was evaluated in 49 nests distributed 16 in 14 locations in Colombia. The formulation application was carried out by direct application, using a pump at a speed of 10 ml/m2. The effectiveness was estimated from the reduction of the flow of ants, evaluating the statistically significant differences using the ANOVA and Tukey-test. RESULTS: Effective control of 90% of the nests was observed in the field phase in 60 days, except in nests with areas > 50 m2 that were located in regions with high rainfall (annual average precipitation above 7000 mm), such as Buenaventura. CONCLUSIONS: In this work, it was demonstrated that the combination of B. bassiana and T. lignorum spores represent a viable alternative for the control of the leafcutter ant, in which the effectiveness is related to several factors, including the size of the nest and the rainfall in the area.


Assuntos
Formigas/microbiologia , Beauveria/patogenicidade , Agentes de Controle Biológico , Controle Biológico de Vetores/métodos , Trichoderma/patogenicidade , Animais , Beauveria/crescimento & desenvolvimento , Colômbia , Esporos Fúngicos , Simbiose , Trichoderma/crescimento & desenvolvimento , Universidades
20.
Ecotoxicol Environ Saf ; 183: 109585, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31509930

RESUMO

The two biological control agents, predatory mite Amblydromalus limonicus Garman & McGregor (Acari: Phytoseiidae) and entomopathogenic fungi (EPF) Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), have the potential to independently suppress the invasive tomato potato psyllid (TPP), Bactericera cockerelli (Sulc), in New Zealand. The integrated strategy of combining the release of predatory mites and EPF may further promote biocontrol of pests. To examine the compatibility of A. limonicus and B. bassiana, we tested the lethal effects of B. bassiana on A. limonicus females on B. cockerelli and calculated the sublethal concentrations of B. bassiana. The effects of sublethal concentrations (LC10 and LC30) of EPF on predatory mite females were assessed on the reproduction parameters of the parental generation (F0). We also evaluated the transgenerational effects of EPF on life table parameters and predation rates of the offspring generation (F1) that was fed on the psyllids. Our results showed that A. limonicus females were susceptible to B. bassiana and the LC50 was 2.2 × 105 conidia mL-1. Sublethal concentrations of EPF (LC30) significantly reduced the fecundity, longevity, oviposition period and predation rates of F0 predatory mite females. However, life table and predation rates of F1 predatory mites were not influenced by sublethal concentrations (LC30), except for the reduction of the preadult and total pre-oviposition period, and the predation rate of F1 males. Also, F1 population parameters including the intrinsic rate of increase (rm), finite rate of increase (λ), gross reproduction rate (GRR), and net reproduction rate (R0) were not significantly influenced by sublethal concentrations (LC10 and LC30). This result suggests that the transgenerational effects of entomopathogenic fungi cannot be carried over to F1. In conclusion, the simultaneous application of both biological control agents does have the potential to control TPP at appropriate intervals during the crop season. Further evaluation in the field will be needed to confirm the viability of this approach to control TPP.


Assuntos
Beauveria/fisiologia , Hemípteros/microbiologia , Lycopersicon esculentum/crescimento & desenvolvimento , Ácaros/fisiologia , Controle Biológico de Vetores/métodos , Animais , Beauveria/patogenicidade , Feminino , Fertilidade/fisiologia , Longevidade/fisiologia , Masculino , Ácaros/microbiologia , Nova Zelândia , Oviposição/efeitos dos fármacos , Comportamento Predatório/fisiologia , Reprodução/efeitos dos fármacos , Estações do Ano
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