|Wintermantel, William - Bill|
|NATWICK, ERIC - University Of California - Cooperative Extension Service|
Submitted to: 3rd Hemipteran-Plant Interactions Symposium Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 4/8/2017
Publication Date: 6/3/2017
Citation: Wintermantel, W.M., Hladky, L.L., Cortez, A.A., Natwick, E.T. 2017. A Tomato necrotic dwarf virus isolate from Datura with poor transmissibility by the whitefly, Bemisia tabaci. 3rd Hemipteran-Plant Interactions Symposium. June 4-8, 2017, Madrid, Spain. p. 132.
Technical Abstract: Tomato necrotic dwarf virus (ToNDV); genus Torradovirus, is a whitefly-transmitted virus that caused significant losses for tomato production in the Imperial Valley of California during the 1980s. The virus causes severe stunting, dwarfing of leaves, foliar and fruit necrosis, and greatly reduced fruit and seed production. ToNDV has a limited host range with an affinity for members of the Solanaceae, and infection of Imperial Valley tomato contributed to the loss of the tomato seed industry from the region. After the loss of tomato production the virus disappeared and was not identified in the region again until 2015 when it was found infecting wild Datura species. Like many other tomato-infecting members of the genus, Torradovirus, ToNDV produces icosahedral virions approximately 30 nm in diameter, and can be transmitted in what appears to be a semipersistent manner by at least three whitefly species; Bemisia tabaci MEAM1 and NW1, Trialeurodes abutilonea, and T. vaporariorum, as well as mechanically and by grafting. The ToNDV genome is composed of two RNA molecules of 7.2 and 4.9 Kb, with both RNAs expressing large polyproteins. Three tomato isolates of ToNDV characterized to date share approximately 97 percent or greater average protein sequence identity and are transmitted efficiently by T. abutilonea and B. tabaci MEAM1 in laboratory studies, whereas transmission by T. vaporariorum appears to be less efficient. A new isolate from Datura shares only 80 and 87% nucleotide identity for RNA1 and 2 of the original ToNDV-R, respectively, whereas the polyproteins encoded by these RNAs share 93 and 96% identity. The Datura isolate has been found infecting new Datura plants from an isolated desert weed plot for two years, suggesting the possibility of either seed transmission in Datura, or more efficient transmission to solanaceous weeds than to tomato.