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Citrus plants presenting the typical huanglongbing (HLB) symptoms have been associated to 16SrIX phytoplasma in the States of Sao Paulo (SP), Minas Gerais (MG), Bahia (BA) and, more recently, Distrito Federal (DF), Brazil. Although in SP and MG states ‘Candidatus Liberibacter asiaticus’ is more commonly associated with HLB, single infection by phytoplasmas also occurs. To date, only 16SrIX phytoplasma induces HLB symptoms in BA and DF, a region free of ‘Ca. Liberibacter spp.’. The objective of this work was to survey for alternative hosts and potential vectors of the 16SrIX phytoplasma in citrus orchards from DF using quantitative real-time PCR (qPCR) detection. Fifty-three specimens encompassing fifteen species of weeds were collected from three Tahiti lime (Citrus latifolia Tanaka) and Ponkan mandarin (Citrus reticulata Blanco) orchards. Only five plants, one Euphorbia sp., one Sida sp., and three Bidens pilosa were positive for the presence of the 16SrIX phytoplasma. Regarding the leafhoppers, 16SrIX phytoplasma was detected in 11/ 38 specimens of Scaphytopius sp. and not detected in 32 specimens of Planicephalus flavicosta. These results suggest that spontaneous vegetation and the leafhoppers Scaphytopius may harbor 16SrIX phytoplasma that can further infect citrus orchards. The capacity of Scaphytopius insects to vector the phytoplasma to citrus plant should be better investigated.

Maize white spot, caused by the bacterium Pantoea ananatis, is one of the main leaf diseases of maize in Brazil. However, until now, its presence in corn seeds has not been detected. In this study, P. ananatis was detected in corn seeds using a semi-selective culture medium. A bacterial suspension of P. ananatis was serially diluted ten-fold and plated on 523, YDC or semi-selective PA20 media, with or without the addition of methyl thiophanate. The detection of bacteria in seeds was evaluated in three seed lot samples, collected from field maize plants with white spot symptoms. Seed washings were prepared, ten-fold serially diluted and plated on the same three culture media. Addition of methyl thiophanate to 532, YDC and PA20 culture media did not inhibit bacterial growth. Pantoea ananatis was detected in two corn seed samples on YDC and PA20 media, which was confirmed by biochemical, physiological and molecular characterization as well as by pathogenicity tests. This is the first report of P. ananatis detection in corn seeds.

Resumo: O objetivo deste trabalho foi avaliar as informações qualitativas e quantitativas sobre as interceptações de pragas ausentes não regulamentadas e quarentenárias em material vegetal importado. As informações sobre interceptações de pragas pelo serviço de quarentena vegetal da Embrapa, no período de 1977 a 2013, foram obtidas em um banco de dados, atas laboratoriais e listas de interceptação publicadas. As interceptações foram analisadas de acordo com regulamentação das pragas, espécie vegetal, parte vegetal importada e origem. O material foi categorizado em sementes botânicas e material de propagação vegetativa. No período do levantamento, foram interceptadas 75 espécies de pragas em 114 eventos de interceptação. Fungos, vírus e ácaros constituem a maior parte das interceptações, e a maioria delas ocorreu em lírio, oliveira, trigo, uva, arroz, batata e maçã. A taxa média anual de infestação/infecção do material vegetal analisado é de 2% dos processos de importação. O material para propagação vegetativa apresentou maior taxa de infestação/infecção por pragas do que as sementes botânicas. Das espécies-pragas interceptadas, 63% não são regulamentadas como quarentenárias para o Brasil. Esses resultados indicam a necessidade premente de revisão da atual lista de pragas quarentenárias do País. Abstract: The objective of this work was to evaluate qualitative and quantitative information on interceptions of quarantine and absent non-regulated pests in imported plant material. Information concerning pest interceptions by Embrapa's plant quarantine service during the period of 1977-2013 was obtained from a database, laboratory reports, and published lists of intercepted pests. Data interceptions were evaluated according to pest regulations, plant species, imported plant parts, and origin of importation. The plant material was categorized as botanical seeds and plant material for vegetative propagation. In the survey period, 75 pest species were intercepted in 114 interception events. Fungi, viruses, and mites were the most intercepted ones, and most interceptions occurred in lily, olive, wheat, grapes, rice, potato, and apple. The average annual rate of infestation/infection of the evaluated plant material was 2% of the import processes. The material for vegetative propagation had a higher rate of infestation/infection with pests than botanical seeds. Of the intercepted pests species, 63% are not regulated as quarantine pests for Brazil. These results indicate the urgent need to review the current list of quarantine pests in the country.

Le Centre national de recherche sur les fruits temperes : historique, objectifs, banques de genes, programmes speciaux (pechers, pommiers, poiriers, pruniers, fraisiers, Rubus, especes indigenes, programmes divers)

RESUMO Ocorrencia de Pseudomonas corrugata causando necrose-da-medula em plantas de tomate em Goias, Brasil Identificou-se Pseudomonas corrugata associada a sintomas de necrose-da-medula em campo de producao de tomate para mesa localizado no municipio de Goianapolis, Goias, em 2006. A bacteria foi identificada por meio de PCR, utilizandose os iniciadores especificos PC5/1 e PC5/2. Realizou-se ainda testes fisiologicos e de patogenicidade que corroboraram na identificacao. No Brasil, P. corrugata havia sido relatada apenas em Sao Paulo e no Rio Grande do Sul.

Em inspeções feitas nos núcleos rurais do Estado do Amapá e nas bases físicas da UEPAE de Macapá/Embrapa, constataram-se sintomas de doenças fúngicas e bacterianas em hortaliças. Exames microscópicos, cultura pura, testes de patogenicidade e bioquímicos confirmaram a diagnose visual das doenças. Made available in DSpace on 2018-03-23T00:39:31Z (GMT). No. of bitstreams: 1 CPAFAP1990DoencasdehortalicasnoAmapa.pdf: 1580887 bytes, checksum: f26d0d4edbed58e5b46b38f382b60edd (MD5) Previous issue date: 2001-07-27