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1.
PLoS One ; 17(8): e0273291, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36037224

RESUMO

In the 21st century, we still need to talk about gender inequality in science. Even with the sharp growth of studies on this theme over the last decades, we are still trying to convince our peers that diversity matters and, if embraced, makes better science. Part of this drawback can be related to the need for data to support effective proposals to change the academic scenario. In order to close some of those gaps, we here analyze 1) the profile of Brazilian researchers based on production, impact, and membership to the Brazilian Academy of Sciences, 2) participation in the Editorial boards of Brazilian journals dedicated to Entomology, and, 3) the academic scenario of Brazilian Entomology focusing on the sex of the first and last authors in peer-reviewed international publications related to Entomology. We aimed to provide a deeper look on the Brazilian Entomology scenario and to expand the amount of data availability to stimulate and foster a mind-change in the current academic structure. We performed scientometric searches and analysis using different platforms and found that the number and impact of the publications by female researchers, as observed by relative numbers, are not less than that of males. Despite that, female researchers are less represented at the Brazilian Academy of Sciences and editorial boards, reinforcing the lack of women recognition in science. Thus, we observe that some narratives related to the productivity gap can be misleading to a perpetuation of our internal and structural biases. We here expanded data from a previous paper where we scrutinized the Brazilian Entomology scenario and discussed the patches and systems that maintain gender gap in science.


Assuntos
Entomologia , Editoração , Brasil , Feminino , Humanos , Masculino , Revisão por Pares
2.
Plants (Basel) ; 11(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35567136

RESUMO

Encapsulation via nanotechnology offers a potential method to overcome limited thermal and photo-stability of botanical pesticides. In this study, nanospheres of essential oils (NSEO) derived from Zanthoxylum rhoifolium Lam. fruit were characterized and evaluated for their photostability and insecticidal activity against Bemisia tabaci. Three major compounds of Z. rhoifolium fruits were detected by CG-MS: ß-phellandrene (76.8%), ß-myrcene (9.6%), and germacrene D (8.3%). The nanoprecipitation method was used to obtain homogeneous spherical NSEO, with ≥98% encapsulation efficiency. Tests with UV/Vis spectrophotometry showed significantly reduced photodegradation from exposed NSEO samples when compared with essential oil (EO) controls. Whitefly screenhouses bioassays with bean plants treated with 0.25, 0.5, 1 and 1.5% suspensions showed EO treatments in both free and nanoencapsulated forms reduced adult whitefly oviposition by up to 71%. In further tests, applications at 1.5% caused ≥64% mortality of second instar nymphs. When the test was conducted under high temperature and light radiation conditions, the insecticidal effect of NSEO treatments was improved (i.e., 84.3% mortality) when compared to the free form (64.8%). Our results indicate the insecticidal potential of EO-derived from Z. rhoifolium fruits with further formulation as nanospheres providing greater photostability and enhanced insecticidal activity against B. tabaci under adverse environmental conditions.

3.
Ecol Evol ; 12(1): e8557, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35127052

RESUMO

During 1991, in Brazil, the presence of the exotic Bemisia tabaci B mitotype was reported in São Paulo state. However, the duration from the time of initial introduction to population upsurges is not known. To investigate whether the 1991 B mitotype outbreaks in Brazil originated in São Paulo or from migrating populations from neighboring introduction sites, country-wide field samples of B. tabaci archived from 1989-2005 collections were subjected to analysis of mitochondrial cytochrome oxidase I (mtCOI) and nuclear RNA-binding protein 15 (RP-15) sequences. The results of mtCOI sequence analysis identified all B. tabaci as the NAFME 8 haplotype of the B mitotype. Phylogenetic analyses of RP-15 sequences revealed that the B mitotype was likely a hybrid between a B type parent related to a haplotype Ethiopian endemism (NAFME 1-3), and an unidentified parent from the North Africa-Middle East (NAF-ME) region. Results provide the first evidence that this widely invasive B mitotype has evolved from a previously undocumented hybridization event. Samples from Rio de Janeiro (1989) and Ceará state (1990), respectively, are the earliest known B mitotype records in Brazil. A simulated migration for the 1989 introduction predicted a dispersal rate of 200-500 km/year, indicating that the population was unlikely to have reached Ceará by 1990. Results implicated two independent introductions of the B mitotype in Brazil in 1989 and 1990, that together were predicted to have contributed to the complete invasion of Brazil in only 30 generations.

4.
Neotrop Entomol ; 50(6): 859-872, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34767178

RESUMO

Although women are about half of world's population, they are underrepresented in many sectors including academia and the research scenario in general. Gender gap in Entomology has been pointed out in other publications; however, data for Brazil has never been demonstrated. Here we provide a diagnosis for the Brazilian Entomology scenario in order to contribute to propositions towards disentangling the gender gap in general. We analyzed scientometric data for Brazilian Entomology focusing on gender disparity and on personal perceptions related to the gender gap through an online questionnaire. We detected a pervasive gender bias in which the scissor-shaped curve is the most representative effect of it: women were the majority in lower degree stages but the minority in higher degree stages (permanent positions and positions of prestige and power). We also observed mentorship bias and discussed these results in light of intersectionality and the COVID-19 pandemic. Gender differences were perceived differently by the questionnaire respondents considering age, gender, and parenting. With this data and analyses, we have provided elements to stimulate and support change to a healthier and more equitable academic space.


Assuntos
COVID-19 , Sexismo , Animais , Brasil , Feminino , Masculino , Pandemias , SARS-CoV-2 , Fatores Sexuais
5.
Microbiol Res ; 216: 12-22, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30269851

RESUMO

Selecting entomopathogenic fungal isolates with resilience to environmental stresses, optimal mass production characteristics, and with high virulence to target pests favors the development of mycopesticides. A case in point, Cordyceps (= Isaria) javanica has been extensively investigated for non-chemical control of whiteflies worldwide. We phylogenetically characterized 11 native C. javanica isolates from Northeastern and Central Brazil. These isolates were screened for tolerance to heat-shock, UV-B radiation, osmotic and oxidative stresses, as well as conidial production on cereal grain and insecticidal activity against the whitefly Bemisia tabaci (MEAM 1) in the laboratory. All isolates were pathogenic to whiteflies and significant (3-fold) differences in median lethal concentration were observed among isolates. Furthermore, pronounced differences among isolates were found for stress factors and conidial production. Using principal component analysis, our results highlighted three major clusters formed by isolates (i) resistant to osmotic and oxidative stress, (ii) resilient to UV-B, and (iii) with high virulence, conidial production and heat tolerance. Overall, isolate CG1228 performed best based on multi-stress resistance, mass production and virulence attributes in the laboratory. This study highlights the importance of exploring natural variation in entomopathogenic fungi for selection of appropriate isolates for effective biocontrol of insect pests coupled with mass production characteristics and abiotic stress tolerances.


Assuntos
Cordyceps/isolamento & purificação , Cordyceps/fisiologia , Fenótipo , Reprodução Assexuada/fisiologia , Estresse Fisiológico/fisiologia , Aclimatação/fisiologia , Brasil , Cordyceps/patogenicidade , Cordyceps/efeitos da radiação , Resposta ao Choque Térmico , Temperatura Alta , Inseticidas , Análise Multivariada , Pressão Osmótica , Estresse Oxidativo , Controle Biológico de Vetores/métodos , Filogenia , Esporos Fúngicos/crescimento & desenvolvimento , Raios Ultravioleta , Virulência
6.
Molecules ; 23(8)2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30115840

RESUMO

The aim of our study was to produce and characterize poly-ε-caprolactone (PCL) nanospheres containing essential oils from Zanthoxylum riedelianum fruit and to evaluate their stability gains as well as their insecticidal and deterrent activities against whitefly (Bemisia tabaci). The PCL nanospheres exhibited a homogeneous spherical morphology, with particle diameters between 106.7 nm and 129.2 nm, pH of approximately 6, zeta potential (ZP) lower than -19.0 mV and encapsulation efficiency higher than 98%. Only 43% of the nanoencapsulated essential oil (NSEO) was degraded in response to ultraviolet light, whereas the essential oil (EO) degraded by 76% over the same period. In a free-choice test, the NSEO and EO reduced the number of whitefly eggs by approximately 70%. NSEO and EO at 1.5% killed 82.87% and 91.23% of 2nd-instar nymphs of whitefly, respectively. Although NSEO displayed lower insecticidal activity, it offers a greater advantage over the free EO, due to protection conferred by polymer against photodegradation. Therefore, its usage may optimize the maintenance of essential oils in the field through photoprotection and controlled release. Our results suggest that the EO of Z. riedelianum fruit can be used for B. tabaci management strategy; nevertheless, the benefits of NSEO require further evaluation at the field level.


Assuntos
Hemípteros , Inseticidas/química , Nanosferas/química , Óleos Voláteis/química , Zanthoxylum/química , Animais , Liberação Controlada de Fármacos , Frutas/química , Ninfa , Óvulo , Tamanho da Partícula , Fotólise , Raios Ultravioleta
7.
Appl Microbiol Biotechnol ; 102(6): 2595-2606, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29417198

RESUMO

The present study aimed to add value to palm oil by-products as substrates to efficiently produce conidia of Beauveria bassiana and Isaria javanica (Hypocreales: Cordycipitaceae) for biological control of the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae), through a solid-state fermentation process using palm kernel cake and palm fiber as nutrient source and solid matrix, respectively. The optimum culture conditions yielded high concentrations of viable conidia after air-drying, when the fungi were grown on palm kernel cake (B. bassiana 7.65 × 109 and I. javanica 2.91 × 109 conidia g-1 dry substrate) after 6 days under optimal growth conditions set to 60% substrate moisture and 32 °C. Both fungal strains exhibited high efficacy against third-instar whitefly nymphs, inducing mortality up to 62.9 and 56.6% by B. bassiana and I. javanica, respectively, assessed after 9 days post-application in a screenhouse. Furthermore, we noted that insect mortality was strongly correlated with high atmospheric moisture, while B. bassiana appeared to require shorter accumulative hours under high moisture to kill whitefly nymphs compared to I. javanica. Our results underpin a feasible and cost-effective mass production method for aerial conidia, using palm kernel as the main substrate in order to produce efficacious fungal bioinsecticides against an invasive whitefly species in Brazil. Finally, our fermentation process may offer a sustainable and cost-effective means to produce eco-friendly mycoinsecticides, using an abundant agro-industrial by-product from Brazil that will ultimately assist in the integrated management of agricultural insect pests.


Assuntos
Beauveria/metabolismo , Cordyceps/metabolismo , Análise Custo-Benefício , Resíduos Industriais , Inseticidas/metabolismo , Animais , Beauveria/crescimento & desenvolvimento , Biotransformação , Brasil , Cordyceps/crescimento & desenvolvimento , Fermentação , Hemípteros/efeitos dos fármacos , Inseticidas/farmacologia , Ninfa/efeitos dos fármacos , Análise de Sobrevida , Temperatura
8.
J Invertebr Pathol ; 127: 93-100, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25805519

RESUMO

Eggs, nymphs (1st-5th instar) and adults of Tibraca limbativentris were challenged by conidial suspensions of its major fungal pathogen Metarhizium anisopliae in order to assess their susceptibility. The role of chemical defensive compounds from exocrine secretions produced by both nymphs and adults were examined for their participation on M. anisopliae infection. Although insect susceptibility to M. anisopliae followed a dose-dependent manner, adults followed by older nymphs displayed the highest resistance. Eggs were highly susceptible showing >96% fungal infection. Crude extracts isolated from metathoracic scent gland and dorsal abdominal glands of adults and nymphs, respectively, showed fungistatic effects by impairing spore germination, vegetative growth and sporulation. Gas chromatography-mass spectrometry analysis of these extracts revealed that the major components were short-chain hydrocarbons (C10-13) and unsaturated aldehydes. In vitro tests with the corresponding synthetic standards indicated compounds with greater antifungal activity including (E)-2-hexenal, (E)-2-octenal, and (E)-2-decenal, with the latter being the most deleterious to fungal fitness. We demonstrated that differential susceptibility of the rice stalk stink bug to M. anisopliae infection is age-specific and partly mediated by fungistatic properties of aldehydes, which are produced by scent glands of both nymphs and adults.


Assuntos
Heterópteros/metabolismo , Heterópteros/parasitologia , Metarhizium , Controle Biológico de Vetores/métodos , Animais , Cromatografia Gasosa-Espectrometria de Massas , Heterópteros/imunologia
9.
World J Microbiol Biotechnol ; 30(5): 1583-90, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24343780

RESUMO

We investigated the potential production and desiccation tolerance of microsclerotia (MS) by Brazilian strains of Metarhizium anisopliae (Ma), M. acridum (Mc) and M. robertsii (Mr). These fungi were grown in a liquid medium containing 16 g carbon l⁻¹ with a carbon:nitrogen ratio of 50:1. One hundred milliliters cultures were grown in 250 ml Erlenmeyer flasks in a rotary incubator shaker at 28 °C and 200 rpm for 5 days. Five-day-old MS were harvested, mixed with diatomaceous earth (DE) and air-dried for 2 days at 30 °C. The air-dried MS-DE granular preparations were milled by mortar + pestle and stored in centrifuged tubes at either 26 or -20 °C. Desiccation tolerance and conidia production were assessed for dried MS granules by measuring hyphal germination after incubation for 2 days on water agar plates at 26 °C and for conidia production following 7 days incubation. Yields of MS by all strains of Metarhizium were 6.1-7.3 × 106 l⁻¹ after 3 days growth with maximum MS yields (0.7-1.1 × 107 l⁻¹) after 5 days growth. No differences in biomass accumulation were observed after 3 days growth, whereas Ma-CG168 showed the highest biomass accumulation after 5 days growth. Dried MS-DE preparations of all fungal strains were equally tolerant to desiccation (≥93 % germination) and the highest conidia production was obtained by MS granules of Mc-CG423 (4 × 109 conidia g⁻¹). All MS granules showed similar stability after storage at either 26 or -20 °C for 3.5 months.


Assuntos
Meios de Cultura/metabolismo , Fermentação , Metarhizium/crescimento & desenvolvimento , Biomassa , Brasil , Carbono/metabolismo , Dessecação , Hifas/crescimento & desenvolvimento , Metarhizium/classificação
10.
Ciênc. rural ; 34(6): 1681-1688, nov.-dez. 2004. tab, graf
Artigo em Português | LILACS | ID: lil-389013

RESUMO

O percevejo-do-colmo, Tibraca limbativentris Stal, 1860 (Heteroptera: Pentatomidae), é altamente prejudicial à cultura do arroz no Brasil, principalmente em sistemas de cultivo irrigados por inundação. O efeito de duas formas de aplicação, conídios em suspensão e veiculados em grãos de arroz autoclavado, da cepa (CP) 172 de Metarhizium anisopliae (Metsch.) Sorok., no controle do percevejo, foi avaliado em três experimentos conduzidos em 1991, 1993 e 1994, em lavoura comercial de arroz irrigado. Em 1991, tanto a pulverização de conídios como a distribuição manual grãos de arroz cobertos com material fúngico em dosagem equivalente a 7,2 x 10(13) conídios.ha-1, sobre o solo e entre os colmos de arroz, onde os percevejos estavam alojados, reduziram significativamente a população natural do inseto com eficiência de controle de 52,6 por cento e 61,8 por cento, respectivamente. Ainda em 1991, estudo sobre o estabelecimento e persistência da cepa no solo do arrozal, com base na contagem de unidades formadoras de colônias (UFC), indicou que o fungo manteve-se viável na entressafra, até 216 dias após a aplicação, época da implantação de novos arrozais. O número de UFC foi maior nas parcelas tratadas com os grãos de arroz cobertos com material fúngico. O crescimento linear do número de UFC, no solo nas parcelas testemunhas, evidenciou disseminação do fungo para partes anteriormente não tratadas do arrozal. Resultados significativos de controle com a aplicação da suspensão de conídios e dos grãos de arroz com o fungo, na dose de 5 x 10(13) conídios.ha-1, também foram obtidos em 1993, com 51,8 por cento e 48,2 por cento de eficiência, respectivamente. Em 1994, a aplicação da suspensão de 5 x 10(13) conídios.ha-1 resultou em 39,5 por cento de controle do inseto. O índice de confirmação de infeção, contudo, foi baixo, nos dois anos, atingindo, no máximo, 20 por cento, em 1993. O baixo número de insetos com micose, em comparação ao índice de mortalidade, pode provavelmente reduzir a taxa de disseminação do fungo nos arrozais e, por conseqüência, ser desfavorável à ocorrência de epizootias.

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