Submitted to: Plant Disease
Publication Type: Peer reviewed journal
Publication Acceptance Date: 4/10/2013
Publication Date: 5/29/2013
Citation: Bextine, B., Aguilar, E., Rueda, A., Caceres, O., Sengoda, V.G., Mc Cue, K.F., Munyaneza, J.E. 2013. First report of 'Candidatus Liberibacter solanacearum' on tomato in El Salvador. Plant Disease. 97:1245. Interpretive Summary: Liberibacter is an economically important plant pathogen that severely damages potato, tomato, pepper, and other related crops. This bacterium is transmitted to these crops by the potato psyllid, a serious insect pest in the United States. Researchers at USDA-ARS Wapato, WA and Albany, CA, University of Texas, and Zamorano University in Honduras discovered that this plant pathogen was also present in El Salvador, where it has caused significant losses to the tomato industry. Tomatoes constitute an important commodity in Central America; therefore, documentation of this bacterium distribution in this country is important to world food security.
Technical Abstract: In April of 2012, tomato plants grown near the town of Yuroconte in the municipality of La Palma in El Salvador, were observed with symptoms resembling those of “Candidatus Liberibacter solanacearum” (Lso) infection. Disease incidence in several fields in the area ranged from 40 to 60%. Heavy infestations of the psyllid Bactericera cockerelli were observed in the affected fields. Leaf samples and psyllids were collected from one of the fields and total DNA was purified from the leaves of 8 and 10 symptomatic and asymptomatic plants, respectively. Pair primers specific for both 16S rDNA (OA2 and OI2c) and surface antigen gene (OMB 1482f and 2086r) of Lso were used to confirm the bacterium presence in infected tomatoes. Four of the eight symptomatic tomatoes (50%) tested positive for the presence of Lso using both primer pairs and no asymptomatic plants were positive for the bacterium. To our knowledge, this is the first report of Lso associated with tomato in El Salvador and the first formal report of the bacterium in the country. This bacterium has caused millions of dollars in losses to the tomato industry in New Zealand, Mexico, and the United States. Tomatoes, as well as many other members of family Solanaceae, are severely damaged by Lso and constitute an important commodity in Central America; therefore, documentation of this bacterium distribution in this country is important to world food security.