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Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 4/14/2017 Publication Date: 6/15/2017 Citation: Wintermantel, W.M. 2017. Tobacco ringspot virus. In: Keinath, A.P., Wintermantel, W.M., Zitter, T.A., editors. Compendium of Cucurbit Diseases and Pests. 2nd edition. St. Paul, MN: APS Press. p. 151-152. Interpretive Summary: Tobacco ringspot virus (TRSV), and its vector, the dagger nematodes (Xiphinema americanum and related species) are widely distributed throughout the world. Cucumber, melon, and watermelon are particularly affected by TRSV. Symptoms can vary with plant age, the strain of the virus, and environmental conditions. Newly infected leaves usually exhibit very bright yellow mosaic or mottle, circular spots (ring spots), leaf spots, necrosis, leaf distortion, and in some cases enations. Watermelon fruit may also develop prominent bumps, pimples, necrotic spots, and ring spots. TRSV, a member of the Nepovirus genus, family Secoviridae, is characterized by isometric particles ranging from 25 to 29 nm in diameter, with each particle encapsidating a one of two single-stranded RNAs. TRSV can be easily detected serologically (ELISA, Western blot) and antiserum can be purchased commercially. Nematodes acquire the virus within 24 hr, and the larval and adult stages transmit it efficiently. Some other vectors have been noted in literature, but transmission by non-nematode vectors is of low efficiency. Seed and pollen transmission has also been documented. Intense cultivation and a methodical removal of known virus reservoir host plants drastically reduce the presence of the vectors and, consequently virus infection. Resistance has been found in several cultivated and wild Cucurbita spp., but no resistant cultivars are currently available. Technical Abstract: Tobacco ringspot virus (TRSV), and its vector, the dagger nematodes (Xiphinema americanum and related species) are widely distributed throughout the world. Cucumber, melon, and watermelon are particularly affected by TRSV. Symptoms can vary with plant age, the strain of the virus, and environmental conditions. Newly infected leaves usually exhibit very bright yellow mosaic or mottle, circular spots (ring spots), leaf spots, necrosis, leaf distortion, and in some cases enations. Watermelon fruit may also develop prominent bumps, pimples, necrotic spots, and ring spots. TRSV, a member of the Nepovirus genus, family Secoviridae, is characterized by isometric particles ranging from 25 to 29 nm in diameter, with each particle encapsidating a one of two single-stranded RNAs. TRSV can be easily detected serologically (ELISA, Western blot) and antiserum can be purchased commercially. Nematodes acquire the virus within 24 hr, and the larval and adult stages transmit it efficiently. Some other vectors have been noted in literature, but transmission by non-nematode vectors is of low efficiency. Seed and pollen transmission has also been documented. Intense cultivation and a methodical removal of known virus reservoir host plants drastically reduce the presence of the vectors and, consequently virus infection. Resistance has been found in several cultivated and wild Cucurbita spp., but no resistant cultivars are currently available. |
