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Passion fruit plants are self-incompatible and fruiting is exclusively dependent on cross-pollination, which in nature is performed by carpenter (mamangava) bees, especially Xylocopa spp. (family Apidae). To ensure satisfactory productivity, daily manual pollination is a common practice among passionflower growers. Therefore, we studied whether manual pollination mechanically transmits the cowpea aphid-borne mosaic virus (CABMV), the causal agent of the passion fruit woodiness disease. None of the eight healthy passion fruit plants manually pollinated with pollen from CABMV field-infected plants were infected, as confirmed by PTA-ELISA and RT-PCR. Healthy passion fruit plants mechanically inoculated with extracts of pollen collected from flowers of CABMV field-infected plants were not infected. CABMV was only detected by RT-PCR in groups of three anthers, and in pollen from groups of 20 anthers collected from flowers of infected passion fruit plants. RT-qPCR conducted with different amounts of pollen grains and anthers indicated extremely low virus titers. In addition to low virus titers, transmission failure may be associated with an absence of virus particles outside the pollen grains and/or absence of enough wounding produced on the stigmas by the fingertips. The improbability of CABMV transmission via pollen during manual pollination showed that this widely used cultural practice is a negligible factor in the epidemiology of passion fruit woodiness disease.

In Brazil, passion flower is grown across almost the entire country. The predominant disease of the passion flower cropis passion fruit woodiness, caused by the potyvirus cowpea aphid-borne mosaic virus (CABMV), and transmitted byaphids in a nonpersistent manner. The disease reduces the useful life of the orchard from 36 months to approximately18 months. Up to now, there has not been an efficient method for disease management. The aim of this work was toevaluate the efficiency of systematic roguing of diseased plants through weekly inspections, for disease management inthe field. The latent and incubation periods of CABMV in passion flower vines were determined in order to optimizeroguing efficiency. Passion fruit plants inoculated with CABMV started to act as sources of inoculum from 3 days afterinoculation (DAI), and the symptoms were expressed, on average, at 8 DAI. Five field experiments, conducted in thestates of S~ao Paulo and Bahia, Brazil, demonstrated that systematic roguing of diseased plants was significantly efficientfor managing passion fruit woodiness disease. In order to facilitate identification and subsequent removal of theinfected plants, they need to be grown separately. This cultural practice can be recommended for managing passionfruit woodiness disease, provided it is applied on a regional scale by all passion fruit growers. The development ofsome pilot plantings for the application of roguing in a passion flower-producing region is recommended to validatethe use of this technique for managing passion fruit woodiness disease. Made available in DSpace on 2020-02-12T18:09:33Z (GMT). No. of bitstreams: 1 Longlastingsystematicroguing2019.pdf: 557891 bytes, checksum: 92a54d52de1484d1506a3b1545811030 (MD5) Previous issue date: 2019

Zucchini lethal chlorosis virus (ZLCV), genus Orthotospovirus, so far was only reported in Brasil. The main natural hosts of ZLCV are in the cucurbit family. Pumpkin (Cucurbita maxima) cultivar Exposicao was previously reported as highly resistant to ZLCV infection. The objectives of this work were to better characterize the resistance of the Exposicao cultivar to ZLCV and to evaluate the interference of potyviruses (papaya ringspot virus type W, PRSV-W, and zucchini yellow mosaic virus, ZYMV) in the ZLCV resistance of this cultivar. C. maxima ‘Exposicao’ and zucchini (C. pepo) ‘Caserta’ (susceptible control) plants were mechanically inoculated with ZLCV in the cotyledons. Resistance to infection and systemic virus movement were evaluated at 7 and 20 days later. Virus detection was performed using PTA-ELISA and RT-PCR in the cotyledons and upper leaves. The interference of the potyviruses in ZLCV resistance was evaluated in greenhouse and field assays. ZLCV was detected in the inoculated cotyledons of both cultivars, but it did not move systemically in C. maxima ‘Exposicao’. The potyviruses PRSV-W and ZYMV did not interfere in the response of C. maxima ‘Exposicao’ to infection with ZLCV. The resistance of ‘Exposicao’ to ZLCV can be explored in future cucurbitaceae breeding programs.

In 2012 and 2013, watermelon (Citrullus lanatus) plants from commercial crops in Sao Paulo State were found showing mosaic, necrotic lesions, leaf deformation and necrotic spots on the fruits, suggestive of tospovirus infection. Leaf and fruit samples were separately tested by PTA-ELISA and reverse transcription polymerase chain reaction (RT-PCR) against tospovirus was performed. The virus was identified as Groundnut ringspot virus (GRSV) and was sap transmissible. The host range was similar to isolates of GRSV found naturally infecting Solanaceae, except that this isolate infected watermelon systemically but did not infect tomato cvs. Santa Clara and Mariana. Thrips collected in the field transmitted GRSV to watermelon, sweet pepper and Nicotiana species. To our knowledge, this is the first report on the natural infection of watermelon by GRSV.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:41Z No. of bitstreams: 1 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) Made available in DSpace on 2013-08-22T18:49:41Z (GMT). No. of bitstreams: 1 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) Previous issue date: 2012-09-01 Made available in DSpace on 2013-09-30T17:45:54Z (GMT). No. of bitstreams: 2 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) S0100-54052012000300012.pdf.txt: 11779 bytes, checksum: f7b89a6efb2acb16c03e3af5bb5165e2 (MD5) Previous issue date: 2012-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:20:27Z No. of bitstreams: 2 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) S0100-54052012000300012.pdf.txt: 11779 bytes, checksum: f7b89a6efb2acb16c03e3af5bb5165e2 (MD5) Made available in DSpace on 2014-05-20T13:20:27Z (GMT). No. of bitstreams: 2 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) S0100-54052012000300012.pdf.txt: 11779 bytes, checksum: f7b89a6efb2acb16c03e3af5bb5165e2 (MD5) Previous issue date: 2012-09-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Entre os problemas fitossanitários da cultura da alface estão as doenças causadas por vírus. Três vírus causam sintomas de mosaico praticamente indistinguíveis: o Lettuce mosaic virus (LMV, Potyvirus), o Lettuce mottle virus (LeMoV, Sequivirus) e o Bidens mosaic virus (BiMV, Potyvirus). Através de RT-PCR utilizando-se oligonucleotídeos específicos para cada um destes vírus, amostras de alface e plantas invasoras, preferencialmente com sintoma de mosaico, foram coletadas em campos de produção de alface das regiões de Mogi das Cruzes, Campinas e Bauru no Estado de São Paulo e analisadas para a presença dos vírus. Verificou-se que o LeMoV foi o vírus encontrado com maior freqüência, seguido do LMV. A ocorrência de BiMV em alface foi extremamente baixa e restrita às regiões de Campinas e Bauru, onde também foi verificado em plantas invasoras como Bidens pilosa e Galinsoga parviflora. Esta ultima é hospedeira dos três vírus. Among the phytosanitary problems affecting lettuce culture are the diseases caused by viruses. Three viruses cause almost indistinguishable mosaic symptoms: Lettuce mosaic virus (LMV, Potyvirus), Lettuce mottle virus (LeMoV, Sequivirus) and Bidens mosaic virus (BiMV, Potyvirus). By RT-PCR using specific primers for each virus, lettuce and weed samples, preferably with mosaic symptoms, and collected from lettuce fields in the regions of Mogi das Cruzes, Campinas and Bauru, São Paulo State, Brazil, were analyzed for the presence of these viruses. LeMoV was the most frequently found virus, followed by LMV. The occurrence of BiMV in lettuce was extremely low and restricted to the regions of Campinas and Bauru, where it was also found in weeds such as Bidens pilosa and Galinsoga parviflora. The latter plant is the host of these three viruses. UNESP Faculdade de Ciências Agronômicas Departamento de Produção Vegetal Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Recursos Genéticos e Biotecnologia UNESP Faculdade de Ciências Agronômicas Departamento de Produção Vegetal

Cucumber ( Cucumis sativus ) fruits and pepper plants ( Capsicum annuum ) cultivated in the same commercial greenhouse in Vitoriana, Sao Paulo, Brazil, in December 2012 and March 2013, respectively, were found with necrotic concentric rings,…