Paulo Sergio Torres Brioso

Complete genome sequence of the sugarcane nitrogen-fixing endophyte Gluconacetobacter diazotrophicus Pal5

BackgroundGluconacetobacter diazotrophicus Pal5 is an endophytic diazotrophic bacterium that lives in association with sugarcane plants. It has important biotechnological features such as nitrogen fixation, plant growth promotion, sugar metabolism pathways, secretion of organic acids, synthesis of auxin and the occurrence of bacteriocins.ResultsGluconacetobacter diazotrophicus Pal5 is the third diazotrophic endophytic bacterium to be completely sequenced. Its genome is composed of a 3.9 Mb chromosome and 2 plasmids of 16.6 and 38.8 kb, respectively. We annotated 3,938 coding sequences which reveal several characteristics related to the endophytic lifestyle such as nitrogen fixation, plant growth promotion, sugar metabolism, transport systems, synthesis of auxin and the occurrence of bacteriocins. Genomic analysis identified a core component of 894 genes shared with phylogenetically related bacteria. Gene clusters for gum-like polysaccharide biosynthesis, tad pilus, quorum sensing, for modulation of plant growth by indole acetic acid and mechanisms involved in tolerance to acidic conditions were identified and may be related to the sugarcane endophytic and plant-growth promoting traits of G. diazotrophicus. An accessory component of at least 851 genes distributed in genome islands was identified, and was most likely acquired by horizontal gene transfer. This portion of the genome has likely contributed to adaptation to the plant habitat.ConclusionThe genome data offer an important resource of information that can be used to manipulate plant/bacterium interactions with the aim of improving sugarcane crop production and other biotechnological applications.

Constatação do Banana streak Uganda B virus em bananeiras no Estado do Pará

O Estado do Para destacou-se, de 1998 a 2000, como o maiorprodutor de bananas do Pais. Em 2005, tornou-se o terceiro colocado,com praticamente a mesma producao do Estado da Bahia, o segundoprodutor nacional. A maior parte da producao de bananas no Para e deareas de agricultores familiares, com baixo nivel tecnologico, e seconcentra na mesorregiao sudeste paraense. A ocorrencia de doencas,porem, tem contribuido para a baixa produtividade dos bananais noPara, destacando-se a sigatoka-negra, sigatoka-amarela, mal-do-Panamae moko. Em tres propriedades rurais, situadas no Municipio de SaoDomingos do Araguaia, foram coletadas amostras de folhas de plantasda cultivar Mysore e Inaja, com sintomas iniciais de estrias cloroticasque evoluiam para necroticas (Fig. 1), culminando com o secamentodas folhas.Das amostras, procedeu-se a extracao dos acidos nucleicos totaise, para a purificacao do DNA, utilizou-se o produto

Obtenção de plantas de feijão-caupi resistentes ao Cowpea severe mosaic virus e ao Cowpea aphid-borne mosaic virus

Among the viruses that infect cowpea (Vigna unguiculata L. Walp.), Cowpea severe mosaic virus (CPSMV) and Cowpea aphid-borne mosaic virus (CABMV) are highlighted for their severity and widespread occurrence, respectively. Therefore, the aim of this study was to obtain and evaluate cowpea plants showing resistance to CPSMV and CABMV in order to develop new and essentially derived cultivars. Eight crosses were performed, followed by backcrosses, using the line TE 97-309G-9 and the cultivar Patativa as resistant parental donors, and the cultivars BR3-Tracuateua, BRS-Urubuquara, BRS-Novaera, BRS-Guariba and Pretinho as susceptible parents. Generations F2 and F2RC1 were challenged for resistance by mechanically inoculating CPSMV and CABMV isolates. In F2RC1 generations, besides resistance, other traits were evaluated: number of days to the beginning of flowering, pod length, number of seeds.pod-1, weight of 100 seeds, and yield of seeds.plant-1. All F2 and F2RC1 individuals were analyzed by the χ2 test and fit to the expected frequency of 15 susceptible plants: 1 plant resistant to both viruses. The means of resistant F2RC1 plants, from each backcross, were compared with the mean of their respective recurrent parent by the t-test and means of backcrosses were compared by the Scott-Knott test. Genetic variability among backcrosses was detected for all traits. All backcrosses were considered promising for obtaining essentially derived cultivars resistant to CPSMV and CABMV, and the selected plants have characteristics that allow the selection of lines with highly productive grains of good commercial quality.

Chanker in Calycophyllum spruceanum in Rio de Janeiro state

) pode atingir quando adulta, 15-40 m de altura/ 4-5 m dediâmetro de copa. Nativa da regiao amazonica, tem crescimento lentoe e utilizada em paisagismo urbano, no reflorestamento, na industriamadeireira e para fins medicinais. Tal planta esta distribuida na Bolivia,Brasil, Colombia, Equador, Peru (Almeida, Inf. Tec. Rede Sem.Amazonia 6:1-2, 2004; Lombard

Variabilidade biológica de isolados do Citrus leprosis virus (CiLV) oriundos de cultivares de laranjeira

ABSTRACT Citrus leprosis, caused by Citrus leprosis virus (CiLV) is one of themajor diseases in citrus orchards in the State of Rio de Janeiro. Theobjective of this study was to compare the development of symptomson Chenopodium amaranticolor inoculated with CiLV isolates from‘Lima’, ‘Pera’ and ‘Seleta’ sweet oranges using three differentdilutions. Five to seven-days after inoculation, necrotic lesionsexhibiting a small chlorotic halo when exposed to the light, were Cunha Junior, J.O.; Pozzer, L.; Brioso, P.S.T. Biological variability of Citrus leprosis virus (CiLV) isolates from sweet orange cultivars. Summa Phytopathologica , v.33, n.3, p.294-296, 2007. RESUMO A leprose, causada pelo Citrus leprosis virus (CiLV), e uma dasprincipais doencas presentes em pomares citricos fluminenses. Oobjetivo deste trabalho foi comparar o quadro sintomatologicodesenvolvido por isolados de CiLV obtidos de cultivares comerciais delaranjeira (Lima, Pera e Seleta), inoculados mecanicamente em Chenopodium amaranticolor,

Espécies de Chrysopidae (Neuroptera) associadas à cultura do tomateiro estaqueado em dois municípios do estado do Rio de Janeiro, Brasil

This research aimed to investigate the diversity of species of lacewings (Chrysopidae) associated to trellised tomato crops in the counties of Cambuci and Seropedica, in Rio de Janeiro State, Brazil. Eggs and adults of chrysopids were collected, manually and by oral suction device, respectively, in Cambuci (commercial farming) and Seropedica (experimental farming). Four species were obtained: Ceraeochrysa cincta (Schneider, 1851), Ceraeochrysa sp1., Chrysopodes elongatus (Freitas; Penny, 2001) and Chrysopodes sp1. in the experimental farming in Seropedica, while in the commercial farming in Cambuci only two species were found: Chrysoperla externa (Hagen, 1861) and Ceraeochrysa cubana (Hagen, 1861).Arq. Inst. Biol., São Paulo, v.82 p. 1-4, 2015 RESUMO: Objetivou-se, com a presente pesquisa, conhecer a diversidade de espécies de crisopídeos (Chrysopidae) em cultivos de tomateiro estaqueado localizados nos municípios de Cambuci e Seropédica, no Rio de Janeiro, Brasil. Ovos de crisopídeos foram coletados manualmente, e os adultos do predador, com o uso de aspirador bucal em lavoura comercial, em Cambuci, e em lavoura experimental, em Seropédica. Em Seropédica foram obtidas quatro espécies de crisopídeos: Ceraeochrysa cincta (Schneider, 1851), Ceraeochrysa sp1., Chrysopodes elongatus (Freitas; Penny, 2001) e Chrysopodes sp1. e em Cambuci, duas espécies: Chrysoperla externa (Hagen, 1861) e Ceraeochrysa cubana (Hagen, 1861).

Orange rust in sugarcane: molecular identification in Rio de Janeiro State

Sugarcane (Saccharum spp.) cultivation is one of the major agricultural activities in the Brazilian states. This study aimed to molecularly identify the pathogen associated with rust in sugarcane cultivars in the state of Rio de Janeiro and to suggest a control strategy. Among the 14 PCR-tested cultivars, Puccinia kuehnii infection was identified for RB947520, RB92606, RB835486, RB72454, SP89-11I5, SP83-2847, both from infected leaf sample and from urediniospores. Puccinia kuehnii was not detected by PCR for the cultivars RB955971, RB951541, RB92579, RB867515, RB855536, SP91-1049, SP80-3280, SP80-1816. This is the first molecular detection of this fungus in the state of Rio de Janeiro for six of the 14 analyzed cultivars.

Ocorrência de Badnavirus em frutos de bananeira no estado do Amazonas, Brasil

RESUMO - A producao brasileira de bananas atende principalmente ao mercado interno, no entanto, em funcao de problemas fitossanitarios, a produtividade dos bananais, principalmente no Estado do Amazonas e extremamente baixa. Recentemente, foi constatada no Estado do Amazonas a ocorrencia de lesoes necroticas de formato irregular, nos frutos de plantas hibridas tetraploides ‘FHIA 01’, ‘FHIA 18’, ‘BRS Caprichosa’, ‘BRS Garantida’, ‘Preciosa’ e ‘Pacovan Ken’ depreciando-os completamente para a comercializacao. Atraves de PCR, utilizando-se dos primers BADNA 1A e BADNA 4 foi detectada a presenca de Badnavirus correlacionada com a estirpe BSV-BR1, e com o Banana streak Uganda B virus. Esta e a primeira vez em que se relatam tais sintomas em frutos associados a Badnavirus, no Pais. Termos para indexacao: Musa spp., Sintomatologia, Polymerase Chain Reaction .

Molecular detection of Xylella fastidiosa in citrus in the state of Para, Brazil

Molecular Detection of Xylella fastidiosa in citrus in the state of Para, Brazil This paper reports the occurrence of chlorosis variegation of citrus (Citrus spp.) in the state of Para, Brazil. The presence of the pathogen was detected by PCR in extracts of total DNA from leaf petioles using specific primes to Xylella