Tomato cultivation in Brazil is threatened by a number of tomato-infecting viruses belonging to the genus Begomovirus of the family Geminiviridae. Here, we report the full DNA-A sequences of three Brazilian begomoviruses: a potentially new tomato-infecting viruses, tomato interveinal chlorosis virus (ToICV), and two previously proposed begomoviruses for which only partial DNA-A sequences are available in the databases: tomato mottle leaf curl virus (TMoLCV) and tomato golden vein virus (TGVV). The complete sequences of the DNA-B components of TMoLCV and TGVV and the DNA-A components of a number of tomato severe rugose virus variants are also presented. Collectively, all of the analyzed sequences were phylogenetically clustered within the two major groups of Brazilian tomato-infecting begomoviruses.

Solanum violaefolium is an ornamental plant, with prostrate, trailing growth habit and is cultivated in shaded areas. A virus that causes ringspot symptoms on its leaves, tentatively named as Solanum violaefolium ringspot virus (SvRSV) and transmitted by Brevipalpus phoenicis (Acari: Tenuipalpidae) was found in Piracicaba city, São Paulo State. It is a bacilliform virus that resembles other cytoplasmic viruses transmitted by Brevipalpus sp. The objective of this work is to describe the biological properties and establish partial molecular characterization of the SvRSV. The SvRSV can be transmitted mechanically to several plant species causing local lesions. Among the tested species, Datura stramonium was proved to be the best experimental host. It was observed that S. violaefolium plants were infested by B. obovatus that also transmitted SvRSV in preliminary Ferreira, P.T.O., Locali-Fabris, E.C., Freitas-Astúa, J., Antonioli-Luizon, R., Gomes, R.T., Machado, M.A., Kitajima, E.W. Characterization of a bacilliform virus isolated from Solanum violaefolium transmitted by the tenuipalpid mites Brevipalpus phoenicis and Brevipalpus obovatus. Summa Phytopathologica, v.33, n.3, p.264-269, 2007 RESUMO Solano-violeta (Solanum violaefolium) é uma planta ornamental rasteira usada para cobrir solos de áreas sombreadas. Um vírus que induz manchas anelares nas folhas desta planta, tentativamente designado Solanum violaefolium ringspot virus -SvRSV, transmitido pelo ácaro Brevipalpus phoenicis (Acari: Tenuipalpidae) foi encontrado em Piracicaba, SP. Trata-se de um vírus baciliforme que se assemelha a outros vírus do tipo citoplasmático transmitidos por Brevipalpus sp. Este trabalho teve como objetivo relatar propriedades biológicas e estabelecer uma caracterização molecular parcial do SvRSV. O vírus pode ser transmitido mecanicamente a várias outras espécies botânicas, causando lesões localizadas. Entre as espécies avaliadas, Datura stramonium mostrou-se a melhor hospedeira experimental. Observou-se também a manifestação de sintomas nestas plantas após infestação das mesmas por B. obovatus previamente alimentado em Ferreira, P.T.O., Locali-Fabris, E.C., Freitas-Astúa, J., Antonioli-Luizon, R., Gomes, R.T., Machado, M.A., Kitajima, E.W. Caracterização de um vírus baciliforme isolado de Solanum violaefolium transmitido pelos ácaros Brevipalpus phoenicis e Brevipalpus obovatus (Acari: Tenuipalpidae). Summa Phytopathologica, v.33, n.3, p. [264][265][266][267][268][269] 2007 Palavras-chave adicionais: SvRSV, CiLV-C, dsRNA, sequenciamento, efeito citopático lesões de SvRSV, confirmando esta outra espécie de ácaro como vetor do vírus. Suas propriedades físicas in vitro foram: temperatura de inativação 40-45 ºC; ponto final de diluição 10 -3 -10 -4 ; longevidade in vitro 12 dias. Em secções ultrafinas, as partículas do SvRSV mostraramse levemente mais delgadas e mais longas que as de outros vírus do mesmo grupo. A partir do dsRNA do SvRSV foi construída uma biblioteca de cDNA e foram identificadas duas possíveis regiões c...

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.