Volume 60 - Tomato Genetics Cooperative - University of Florida

Research Papers TGC REPORT VOLUME 60, 2010
Preliminary report on association of ‘Candidatus Liberibacter solanacearum’
with field grown tomatoes in Guatemala
Luis Mejía, Amilcar Sánchez, and Luis Méndez, Facultad de Agronomía, Universidad
de San Carlos de Guatemala; D. P. Maxwell, Department of Plant Pathology,
University of Wisconsin-Madison; R. L. Gilberston, Department of Plant Pathology,
University of California-Davis; V.V. Rivera and G.A. Secor, Department of Plant
Pathology, North Dakota State University, Fargo.
Introduction
A new disease of tomatoes has received considerable attention in the local
newspapers in Guatemala. Locally, it is referred to “Paratrioza disease”, which refers
to the insect associated with symptomatic plants. The symptoms on tomatoes are
flower abortion, purple margins of youngest leaves, upward cupping of leaves,
thickened stems and retarded internode growth, and stunting of the plants (Fig. 1). In
Mexico, a disease of tomato with similar symptoms is called permanent damage
disease or permanent yellowing disease (daňo permanente del tomate; Páramo
Menchaca, 2007) and Munyaneza et al. (2009) reported that Candidatus Liberibacter
solanacearum was associated with these plants. This unculturable bacterium is
transmitted by the tomato/potato psyllid (Bactericerca (Paratrioza) cockerelli).
Fig. 1. Typical symptoms associated with “Paratrioza disease” of tomato in
Guatemala. Image taken December 2009 and shows flower abortion, purple leaf
margins, cupping of leaves and thickened petioles and stems.
In a tomato field (about 0.7 ha, at 1,500 m, Department of Sacatepéquez) where
symptom incidence was over 90%, samples of young leaves with typical symptoms
were collected in December 2009. DNA was extracted at San Carlos University,
Guatemala City (Garcia et al., 2007). PCR was performed at North Dakota State
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