Investigation on the transmission of some Tobamoviruses by pollen and seed in pepper (Capsicum annuum L.)

Five pepper cultivars were mechanically inoculated with isolates of three Tobamovirus species, viz. the "Gelb" strain of tobacco mosaic virus (TMV-G), the XM-isolate of dulcamara yellow fleck virus (DYFV-XM) and the Nov/H isolate of pepper mild mottle virus (PMMV-Nov/H), respectively. Symptoms caused by the viruses were characterised. The viruses were sucessfully re-isolated from different organs (roots, leaves, fruit parts) of susceptible peppers to test plants. It was estabilished, that the pollen of diseased peppers carried infective virions at least on their surface. Washes of seeds were highly infective, but no infectivity was found after treatment of the seeds with 2% NaOH or 10% Na3PO4. No infectivity of inocula prepared from seed-coats of alkaline treated seeds was established. Infection of young seedlings grown from untreated seeds was demonstrated, while the seedlings came from alkaline treated seeds remained free of infective virus. The possible role of pollen and seed in the epidemiology of Tobamoviruses pathogenic to pepper as well as the importance of seed treatment is discussed.

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Avaliação da resistência a tobamovirus em acessos de Capsicum spp.

Summa Phytopathologica ◽

10.1590/s0100-54052009000100006 ◽

2009 ◽

Vol 35 (1) ◽

pp. 39-43 ◽

Cited By ~ 2

Author(s):

Márcia Aparecida Cezar ◽

Renate Krause-Sakate ◽

Marcelo Agenor Pavan ◽

Cyro Paulino da Costa

Keyword(s):

Tobacco Mosaic Virus ◽

Mosaic Virus ◽

Capsicum Annuum ◽

Mottle Virus ◽

Tomato Mosaic Virus ◽

Pepper Mild Mottle Virus ◽

Nicotiana Glutinosa ◽

Capsicum Spp

A resistência em Capsicum spp a tobamovírus é governada pelos genes L¹ a L4. Baseado na capacidade de alguns isolados suplantarem a resistência destes genes, os tobamovírus podem ser classificados nos patótipos P0, P1, P1-2 e P1-2-3. No Brasil, até o momento as três espécies de tobamovírus conhecidas são: Tobacco mosaic virus (TMV), Tomato mosaic virus (ToMV), pertencentes aos patótipos P0 e Pepper mild mottle virus (PMMoV) pertencente ao patótipo P1-2, respectivamente e podem infectar pimentas e pimentões. Oitenta e seis genótipos de pimentão e pimenta foram avaliados quanto à resistência a tobamovírus, sendo 62 de Capsicum annuum, 18 de C. baccatum e seis de C. chinense. Oito acessos de C. annuum, seis de C. baccatum e os acessos ICA #39, Pimenta de cheiro e PI 152225 de C. chinense apresentaram reação de hipersensibilidade ao ToMV, enquanto que o acesso Ancho de C. annuum foi considerado tolerante, permanecendo assintomático, porém permitindo a recuperação do vírus quando inoculado em Nicotiana glutinosa. Para o PMMoV patótipo P1,2 foram avaliados os acessos de pimentão e pimenta considerados resistentes ao ToMV. Somente o PI 152225 de C. chinense desencadeou reação de hipersensibilidade ao PMMoV, sendo fonte potencial de resistência para programas de melhoramento a este vírus no Brasil.

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Interaction of the Tobacco Mosaic Virus Replicase Protein with the Aux/IAA Protein PAP1/IAA26 Is Associated with Disease Development

Journal of Virology ◽

10.1128/jvi.79.4.2549-2558.2005 ◽

2005 ◽

Vol 79 (4) ◽

pp. 2549-2558 ◽

Cited By ~ 79

Author(s):

Meenu S. Padmanabhan ◽

Sameer P. Goregaoker ◽

Sheetal Golem ◽

Haiymanot Shiferaw ◽

James N. Culver

Keyword(s):

Tobacco Mosaic Virus ◽

Mosaic Virus ◽

Protein S ◽

Helicase Domain ◽

Auxin Response ◽

Disease Symptoms ◽

Developmental Abnormalities ◽

Replicase Protein ◽

Transcriptional Alterations

ABSTRACT Virus-infected plants often display developmental abnormalities that include stunting, leaf curling, and the loss of apical dominance. In this study, the helicase domain of the Tobacco mosaic virus (TMV) 126- and/or 183-kDa replicase protein(s) was found to interact with the Arabidopsis Aux/IAA protein PAP1 (also named IAA26), a putative regulator of auxin response genes involved in plant development. To investigate the role of this interaction in the display of symptoms, a TMV mutant defective in the PAP1 interaction was identified. This mutant replicated and moved normally in Arabidopsis but induced attenuated developmental symptoms. Additionally, transgenic plants in which the accumulation of PAP1 mRNA was silenced exhibit symptoms like those of virus-infected plants. In uninfected tissues, ectopically expressed PAP1 accumulated and localized to the nucleus. However, in TMV-infected tissues, PAP1 failed to accumulate to significant levels and did not localize to the nucleus, suggesting that interaction with the TMV replicase protein disrupts PAP1 localization. The consequences of this interaction would affect PAP1's putative function as a transcriptional regulator of auxin response genes. This is supported by gene expression data indicating that ∼30% of the Arabidopsis genes displaying transcriptional alterations in response to TMV contain multiple auxin response promoter elements. Combined, these data indicate that the TMV replicase protein interferes with the plant's auxin response system to induce specific disease symptoms.

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Challenging the Role of Microtubules in Tobacco Mosaic Virus Movement by Drug Treatments Is Disputable

Journal of Virology ◽

10.1128/jvi.00453-06 ◽

2006 ◽

Vol 80 (13) ◽

pp. 6712-6715 ◽

Cited By ~ 25

Author(s):

Mark Seemanpillai ◽

Rabab Elamawi ◽

Christophe Ritzenthaler ◽

Manfred Heinlein

Keyword(s):

Tobacco Mosaic Virus ◽

Mosaic Virus ◽

Movement Protein ◽

Viral Rna ◽

Virus Movement ◽

Direct Role ◽

Microtubule Inhibitors ◽

Microtubule Polymerization ◽

Drug Treatments

ABSTRACT The movement protein (MP) of Tobacco mosaic virus interacts with microtubules during infection. Although this interaction is correlated with the function of MP in the cell-to-cell transport of viral RNA, a direct role of microtubules in the movement process was recently challenged by studies involving the treatment of plants with inhibitors of microtubule polymerization. Here, we report evidence suggesting that such treatments may not efficiently disrupt all microtubules. Thus, results obtained from studies using microtubule inhibitors may have to remain open to interpretation with regard to the involvement of microtubules in viral RNA trafficking.

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