Submitted to: Tomato Disease Workshop
Publication Type: Abstract Only
Publication Acceptance Date: November 6, 2010
Publication Date: November 16, 2010
Citation: Ling, K. 2010. Genetic Diversity of Tomato Viroids in North America. Tomato Disease Workshop. P33. Technical Abstract: The North American greenhouse tomato industry has expanded dramatically in the last couple of decades. Nearly 40% of fresh tomatoes in the U.S. supermarkets are now produced in greenhouses. The intense production practices and the protective plant growing environment resulted in a number of unique viral disease problems. In addition to the endemic Pepino mosaic virus, tomato chlorotic dwarf disease has recently emerged in a number of greenhouse production facilities in North America, including Canada, Mexico and the U.S. Three distinct viroids have been identified. Tomato chlorotic dwarf viroid (TCDVd) was identified in Arizona, Mexican papita viroid (MPVd) in Canada and Mexico, and Potato stpindle tuber viroid (PSTVd) in California. Sequence analysis to an approximately 100 cloned viroid genomes generated by PCR in selected field samples revealed the presence of high percentage of mutants in addition to the dominant genotype, comprising of a quasispecies nature. The challenge facing such quasispecies in accurate viroid detection, disease epidemic and management will be discussed.