Chlorotic spots have been observed in plants of Clerodendrum x speciosum growing in residential gardens and parks in Piracicaba, SP, Brazil. Thin sections of diseased tissues revealed characteristic cytopathic effects of the nuclear type of the Brevipalpus (Acari: Tenuipalpidae) mitetransmitted viruses (BTrV). Brevipalpus mites, identified as B. phoenicis, infesting symptomatic C. x speciosum plants transmitted the pathogen to healthy C. x speciosum and to C. thomsonae, Gomphrena globosa, Hibiscus cannabinus, H. coccineus, H. schizopetalus, Salvia leucantha, Spathiphyllum wallasi and Tetragonia expansa causing chlorotic spots on their leaves. Mechanical inoculation using leaf extracts from infected C. x speciosum resulted in chlorotic spots on inoculated C. x speciosum, Chenopodium quinoa, C. amaranticolor, G. globosa, H. cannabinus, H. coccineus and T. expansa leaves. C. amaranticolor and C. quinoa kept at 28 -30°C became systemically infected. The same cytopathic effects caused by the nuclear type of BTrV were seen in tissues from all infected test plants by electron microscopy. The virus was purified from systemically infected leaves of C. amaranticolor and C. quinoa. A polyclonal antiserum obtained from an immunized rabbit presented a strong reaction with the homologous antigen in ELISA tests. The results suggest that this chlorotic spot disease of C. x speciosum is caused by a new species of the nuclear type of BTrV, tentatively named Clerodendrum chlorotic spot virus (ClCSV). 2006b). The only exception is OFV which has been found worldwide in orchids (Kondo et al., 2003). This study presents a detailed description of the transmission and host range of a new species of a nuclear type of BTrV isolated from the chlorotic spots on leaves of C. x speciosum, which is tentatively named Clerodendrum chlorotic spot virus (ClCSV). Results of cytopathology, purification and serology are also reported. MATERIAL AND METHODSVirus source -Clerodendrum x speciosum plants growing in Piracicaba, State of São Paulo, Brazil (22º43'S and 47º38'W) exhibiting chlorotic spots on the leaves and heavily infested with B. phoenicis were used as source of inoculum of the virus. Infection was confirmed by the presence of the nuclear type of BTrV by electron microscopy.Mite transmission assays -adult mites, identified as B. phoenicis were collected with a fine needle from symptomatic C. x speciosum plants and transferred to 39 species of test-plants (Tables 1 and 2) grown in pots in a greenhouse. Three plants of each species were used in the transmission tests, placing ten adult mites on four leaves of each tested plant. C. x speciosum plants not infested by mites were used as control. The mites were kept on the plants for five days. After eliminating the mites with chemical sprays, they were kept for symptom development and, subsequently, analyzed by electron microscopy.

RESUMO -Enterolobium contortisiliquum Vell. Morong (Leguminosae-Mimosoideae) é uma espécie muito utilizada em programas de recuperação de matas ciliares no Baixo Rio São Francisco, devido ao seu rápido crescimento inicial. Assim, o objetivo deste trabalho foi avaliar, por meio de marcadores moleculares RAPD, a diversidade genética de oito indivíduos de uma população remanescente dessa espécie, visando contribuir para a definição de estratégias de coleta de sementes. Os indivíduos estão situados em uma área de 100 ha de mata ciliar do Baixo Rio São Francisco. Para a extração do DNA, pelo método CTAB 2%, foram utilizadas folhas tenras dos indivíduos. Testaram-se 20 oligonucleotídios de 10 bases de seqüência arbitrária, cujos produtos foram separados em gel de agarose 0,8%, submetidos à eletroforese horizontal, corados com brometode-etídio e visualizados em luz ultravioleta. A similaridade genética entre os indivíduos foi calculada pelo Coeficiente de Similaridade de Jaccard e a construção do dendrograma, realizada utilizando-se o método UPGMA. O valor médio de diversidade genética entre as matrizes foi de 49%, variando de 33 a 85%. Os indivíduos 6 e 7 apresentaram relativa proximidade genética (67%), não sendo indicado o plantio de suas mudas ou semeadura direta para recuperação de área ciliar em locais muito próximos. A partir dos resultados observados, podem-se desenvolver estratégias para a coleta de sementes e produção de mudas, auxiliando, assim, programas de restauração ambiental.Palavras-chave: Recuperação de área degradada, marcadores de DNA, vegetação ciliar e caráter de raridade. GENETIC DIVERSITY OF Enterolobium contortisiliquum (Vell.) Morong. IN THE LOW SAN FRANCISCO RIVER BY RAPD MARKERS

Este trabalho teve por objetivo verificar a viabilidade de utilização da técnica de PCR, usando primers considerados específicos, para identificação de Xanthomonas axonopodis pv. phaseoli (Xap) e X. axonopodis pv. phaseoli var. fuscans (Xapf), visando criar bases para sua utilização em diagnose rotineira e em programas de certificação de sementes. Foram incluídos no estudo 42 isolados da bactéria provenientes de locais distintos, além de outros gêneros, espécies e patovares, para ser verificada a especificidade dos primers. Os resultados obtidos permitem concluir que os primers utilizados são adequados para identificação de Xap e Xapf, embora dois isolados patogênicos não tenham sido amplificados. Foi observada também a amplificação de uma banda fraca para X. axonopodis pv. vitians, com o mesmo número de pares de bases, o que sugere existir homologia entre estes patovares, na região amplificada.Palavras-chave adicionais: Phaseolus vulgaris, crestamento bacteriano do feijoeiro, caracterização molecular.The objective of this study was to determine the availability of PCR technique as a tool for Xanthomonas axonopodis pv. phaseoli (Xap) and X. axonopodis pv. phaseoli var. fuscans (Xapf) identification. The specificity of the primers was tested based on the DNA amplification of 42 isolates of bacteria collected at several locations. The primers were capable of identifying Xap and Xapf, although two virulent isolates were not detected. The amplification of a weak band, which was observed for X. axonopodis pv. vitians, suggests homology between these pathovars, in the same region. ABSTRACTIdentification of Xanthomonas axonopodis pv. phaseoli and X. axonopodis pv. phaseoli var. fuscans through the PCR technique INTRODUÇÃO

African oil palm (Elaeis guineensis Jacq.) is considered the most productive oleaginous crop due to its high oil production per hectare. In April 2015, E. guineensis leaves showing elliptical necrotic spots with yellowish halo were observed in a commercial plantation in Moju, Pará state, Brazil. A synematous fungus was consistently observed associated with the necrotic spots. The aim of this study was to identify this fungus associated with E. guineensis in Brazil. Based on morphology and DNA sequence data of the internal transcribed spacer rDNA, the fungus was identified as Helminthosporiella stilbacea. Helmintosporiella stilbacea has been reported associated with leaf spots on E. guineensis in Africa, Ghana, Sudan and Zambia. To the best of our knowledge, this is the first report of H. stilbacea associated with E. guineensis in Brazil.

The cubiu (Solanum sessiliflorum) fruit, originating in the Amazon basin, is commonly used in that region for food, medicine, and cosmetics. In an experimental culture of cubiu, in order to evaluate its adaptation to conditions in the Northern region of the state of Rio de Janeiro, it was observed plants with mosaic symptoms. A cubiu plant was collected and analyzed to identify the etiological agent. After mechanical passage through a local lesion host, a host range test was performed. The virus induced chlorotic local lesions in Chenopodium quinoa, necrotic local lesions in Gomphrena globosa, mosaic in S. sessiliflorum, leaf and stem necrosis in tomato (Lycopersicon esculentum) 'Rutgers', mosaic and leaf distortion in Datura stramonium and Physalis floridana, and necrotic local lesions followed by systemic necrosis and plant death in four Nicotiana species. Electron microscopic observations of ultra thin sections from infected cubiu leaves showed the presence of spheroidal, membrane-bound particles typical of tospovirus species. Analysis of the nucleocapsid protein from concentrated virus particles indicated the presence of a 28 kDa protein. RT-PCR was performed after total RNA extraction from infected IPA-6 tomato leaves. A fragment of approximately 0,8 kbp corresponding to the N gene was amplified, cloned and sequenced. The N protein from the cubiu isolate was 95% homologous to the Groundnut ringspot virus (GRSV) protein, and no more than 85% homologous to those from Zucchini lethal chlorosis virus (ZLCV) and Chrysanthemun stem necrosis virus (CSNV), Tomato spotted wilt virus (TSWV), and Tomato chlorotic spot virus (TCSV). This is the first report of the occurrence of GRSV (or any other plant virus) in cubiu.

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di studio del CNR sui virus e le virosi delle colture mediterranee, via Amendola 165/A, 70126Bari (Italy) **Istituto Agronomico Mediterraneo, via Cegli 9, 70010 Valenzano, Bari (Italy) The biological and physicochemical characterization of two almond isolates of prune dwarf ilarvirus (PDV), carried out in comparison with six other PDV isolates from other Prunus species, showed that the various isolates could not be differentiated from one another, if it were not for the field syndromes they were associated with. To ascertain the occurrence of serological PDV variants in nature, monoclonal antibody technology was applied. One PDV isolate (PDV-IAM1 1) from Prunus mahuleb in Puglia (Southern Italy) was used as antigen. After fusion of murine (balb/C) splenocytes with NSO/l myeloma cells, eight different hybridoma lines secreting PDV-IAM11-specific antibodies were selected, cloned, and denoted PD-3, PD-6, PD-7, PD-8, PD-9, PD-10, PD-11 and PD-12. Their use in the serological characterization of the eight PDV isolates under study, by DAS-ELISA, gave rise to three different serotype groups, one of which (PDV-B) comprised only the two almond isolates. Examination of 120 additional samples collected from field-grown PVD-infected Prunus trees (40 of which were almonds) confirmed the existence in nature of a wide range of serological PDV variants, which yielded 36 different types of reactants (tentative serogroups). The PDV-B serotype was detected in 38% of the almond trees tested, but only in three of the other 86 PDVinfected Prunus plants. These results demonstrate that serological differentiation among PDV isolates is possible, and that PDV-B, one of the tentative serotypes identified, seems preferentially associated with almond. Production d'anticorps monoclonaux du prune dwarf ilarvirus et leur utilisation pour la caracterisation serologique de ses isolats sur amandierLa caracthisation biologique et physico-chimique de deux isolats de l'amandier du prune dwarf ilarvirus (PDV), rCalisCe en comparaison avec six isolats d'autres esp&ces de Prunus, a montrk que les diffkrents isolats ne peuvent pas &re distinguis les uns des autres, sauf pour les sympdmes qu'ils provoquent en plein champ. La technologie des anticorps monoclonaux a Ct C utiliste pour vCrifier l'existence dans la nature de variants sCrologiques du PDV. Un isolat (PDV-IAM1 1) de Puglia (sud de 1'Italie) provenant de Prunus mahaleb a CtC utilisi c o m e antigbne. Aprks fusion de splknocytes munns (balb/C) avec des cellules de myClome NSO/l, huit lignCes hybrides sCcrCtant des anticorps spCcifiques ? i PDV-JAM1 1 ont Ct C sklectionnbes, clonies, et nomkes PD-3, PD-6, PD-7, PD-8, PD-9, PD-10, PD-11 et PD-12. Leur utilisation pour la caractkrisation sCrologique, par DASI-ELISA, des huit isolats de PDV Ctudiks a permis de dCgager trois groupes de skrotypes, dont un (PDV-B) comprend uniquement les deux isolats de l'amandier. L'Ctude de 120 Cchantillons supplementaires pr6levCs sur des Prunus cultivts en plein champ et infect& par le PDV (dont 40 amandiers), a c...

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