ARS | Publication request: A novel M RNA reassortant of Groundnut ringspot virus and Tomato chlorotic spot virus infecting vegetables in Florida

Submitted to: American Phytopathological Society
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 2011
Publication Date: July 15, 2011
Citation: Webster, C.G., Reitz, S.R., Frantz, G., Mellinger, H., Perry, K.L., Adkins, S.T. 2011. A novel M RNA reassortant of Groundnut ringspot virus and Tomato chlorotic spot virus infecting vegetables in Florida. American Phytopathological Society. Abstract.

Technical Abstract: Groundnut ringspot virus (GRSV) was recently identified using serology and nucleocapsid gene sequence from tomato plants with severe tospovirus symptoms in south Florida, which extends the geographic range of this virus from South America and South Africa to now include North America. Full genome sequence analysis demonstrated that the Florida GRSV isolate was actually an M RNA reassortant with the S and L RNA segments coming from GRSV but with the M RNA segment coming from Tomato chlorotic spot virus (TCSV), a related but genetically distinct tospovirus species described in South America. This is the first report of a natural reassortant (i.e. LGMTSG) between two tospovirus species. Regions of each of the three genomic RNA segments were sequenced to confirm that the LGMTSG genotype was present in tomato samples collected in five south Florida counties starting in December 2009. The LGMTSG genotype was also detected in pepper and tomatillo with typical tospovirus symptoms in December 2010. Western flower thrips (Frankliniella occidentalis) transmitted the LGMTSG genotype and other thrips species are currently being investigated for their ability to transmit this virus. Neither parental genotype (GRSV or TCSV) nor alternate reassorted genotypes have been detected in any samples. These results suggest that LGMTSG was introduced to the U.S. in its current form and that reassortment between distinct tospovirus species may be more frequent than previously thought.