Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/23/2011
Publication Date: 7/29/2011
Citation: Ling, K., Lin, H., Lewis Ivey, M.L., Zhang, W., Miller, S. 2011. First Report of 'Candidatus Liberibacter Solanacearum' Naturally Infecting Tomatoes in the State of Mexico, Mexico. Plant Disease. 95:1026. Interpretive Summary: Candidatus Liberibacter solanacearum (Lso) is a simple plant pathogenic bacterium which was first identified on greenhouse tomatoes in New Zealand in 2008. Since then, it has been implicated in causing several serious disease outbreaks on solanaceous crops (i.e., potato, tomato, pepper) in North and Central America and most recently on carrot in Europe. Lso was previously identified on field tomatoes in Western Mexico. In the present study, we detected the presence of this bacterium on greenhouse tomatoes in Eastern Mexico. Identification of this bacterium on a different cropping system over a greater geographical distribution implicates that the multi-billion dollar field and greenhouse tomato industries in North America are at risk to this emerging disease.
Technical Abstract: Tomato (Solanum lycopersicum) plants exhibiting stunting, yellow mosaic, short, chlorotic leaves, aborted flowers and reduced-size fruits, symptoms similar to those exhibited by plants infected by Candidatus Liberibacter solanacearum (Lso), were observed in greenhouses in Jocotitlan, Mexico. In addition to the detection of Pepino mosaic virus and Mexican papita viroid, Lso-specific PCR products (1,168bp and 669-bp) were also amplified by PCR in two (MX11-02 and MX11-05) of eight samples collected using primers OA2 and OI2c or CL514F/CL514R, respectively. Both 16S rRNA and 50S gene sequences in MX11-05 were identical to the Lso previously identified in potatoes in Mexico and recently classified as the “b” haplotype. On the contrary, the Lso from field tomato in Western Mexico were designated as the “a” haplotype. Lso was first identified in greenhouse tomatoes in 2008 in New Zealand. It has also been identified to infect greenhouse and field tomatoes in the U.S. This is the first report of Lso naturally infecting greenhouse tomatoes in Mexico.