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1.
Bull Entomol Res ; 110(4): 487-496, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31987066

RESUMO

The whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is one of the most important agricultural pests and virus vectors worldwide. Bemisia tabaci is considered a complex of cryptic species with at least 44 species. Among them, the species Middle East-Asia Minor 1 (MEAM1, formerly B biotype) and Mediterranean (MED, formerly Q biotype) are the most important, and they have attained global status. In Brazil, MEAM1 was first reported in the 1990s and is currently the predominant species in the country, meanwhile, MED was recently reported in the South and Southeast regions and was found to be mainly associated with ornamental plants. Currently, an increasing problem in the management of whitefly infestations in greenhouses associated with bell pepper was observed in São Paulo State, Brazil. The whiteflies were collected and identified based on a microsatellite locus (primer pair BEM23F and BEM23R) and the mitochondrial cytochrome oxidase I gene followed by restriction fragment length polymorphism analysis and sequencing. We observed that MED was the predominant species collected on bell pepper, but it was also found on tomato, cucumber, eggplant, and weeds grown in greenhouses. In open field, we found MED on tomatoes, bell peppers, and eggplants. In addition, MED was identified in Goiás State in association with ornamental plants. The begomovirus Tomato severe rugose virus and the crinivirus Tomato chlorosis virus was detected on bell pepper and tomato, respectively. Only MED specimens were found associated with the virus-infected plants. Moreover, we also investigated the endosymbionts present in the MED whiteflies. The collected populations of B. tabaci MED harbored a diversity of secondary endosymbionts, with Hamiltonella (H) found predominantly in 89 specimens of the 129 tested. These results represent a new concern for Brazilian agriculture, especially for the management of the newly introduced whitefly MED species, which must be implemented to limit the spreading and establishment of this pest in different crops in this country.


Assuntos
Produtos Agrícolas , Hemípteros/classificação , Hemípteros/virologia , Animais , Begomovirus/isolamento & purificação , Brasil , Crinivirus/isolamento & purificação , Surtos de Doenças , Hemípteros/genética , Espécies Introduzidas , Repetições de Microssatélites , Doenças das Plantas/virologia , Simbiose , Verduras
2.
Acta amaz ; 47(4): 293-300, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-885978

RESUMO

ABSTRACT The bacurizeiro (Platonia insignis Mart.) is a tree native to the Amazon whose fruit is much used in the gastronomy in the North and Northeast regions of Brazil. Due to its great economic potential for these regions, the species is being conserved in germplasm banks to support genetic breeding programs. The aim of this work was the molecular characterization of P. insignis accessions belonging to the germplasm bank of the Embrapa Eastern Amazon research unit using ISSR (Inter Simple Sequence Repeat) markers. Seventy-eight accessions of P. insignis belonging to 16 progenies were sampled in two different localities on Marajó Island, state of Pará, Brazil. Among the 16 progenies, seven were collected in Soure and nine in Salvaterra. The 78 accessions were genotyped with 23 pre-selected primers. We obtained 121 amplified products, of which 54 were polymorphic. The most polymorphic primers were UBC 834, UBC 899 and UBC 900. Primers UBC810 and UBC884 did not amplify polymorphic bands. Forty-nine markers out of 54 were selected for genetic analyses. AMOVA within and among progenies showed low genetic differentiation (ΦPT = 0.064, P<0.001) with higher diversity within progenies (96%), low genetic differentiation among sampling localities (ΦPT = 0.025, P<0.013), and higher diversity within (98%) than among localities. Clustering by UPGMA based on Jaccard similarities among pairs of accessions did not separate genotypes according to progeny or sampling localitiy. We recommend that new germplasm surveys consider a greater sampling effort within sampling localitites.


RESUMO O bacurizeiro (Platonia insignis Mart.) é uma espécie frutífera nativa da Amazônia muito utilizada na cultura alimentar nas regiões Norte e Nordeste do Brasil. Devido a seu grande potencial econômico regional, a espécie vem sendo conservada em bancos ativos de germoplasma (BAG) para apoiar programas de melhoramento genético. Dessa forma, o objetivo deste trabalho foi caracterizar molecularmente acessos de P. insignis pertencentes ao BAG da Embrapa Amazônia Oriental por meio de marcadores ISSR (Inter Simple Sequence Repeat). Foram coletados 78 acessos de P. insignis pertencentes a 16 progênies coletadas em dois locais diferentes na Ilha de Marajó, PA. Das 16 progênies, sete foram coletadas em Soure e nove em Salvaterra. Os 78 acessos foram genotipados com 23 primers ISSR pré-selecionados. Obteve-se 121 produtos amplificados, dos quais 54 foram polimórficos. Os primers mais polimórficos foram UBC 834, UBC 899 e UBC 900. Já os primers UBC810 e UBC884 não apresentaram bandas polimórficas. Das 54 marcas, 49 foram selecionadas para as análises genéticas. A AMOVA entre e dentro de progênies identificou baixa diferenciação genética (ΦPT = 0,064, P<0,001) com maior diversidade dentro de progênies (96%), bem como baixa diferenciação genética entre os locais de coleta (ΦPT = 0,025, P<0,013), com maior diversidade dentro (98%) do que entre locais. O agrupamento pelo método UPGMA, com base nas similaridades de Jaccard entre os acessos, não separou as amostras por progênie ou local de coleta. Recomenda-se que novas coletas de germoplasma considerem maior esforço de coleta em cada local amostrado.


Assuntos
Variação Genética
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