January 27, 2003
From: American Phytopathological Society, Plant Disease Notes [edited]

Bacterial Spot of tomato and pepper caused by Xanthomonas axonopodis pv. vesicatoria in the Western Mediterranean region of Turkey
H. Basim, University of Akdeniz, Faculty of Agriculture, Department of Plant Protection, 07050, Antalya, Turkey; E. Basim, University of Suleyman Demirel, Faculty of Agriculture, Department of Plant Protection, 32260, Isparta, Turkey; and J. B. Jones, G. V. Minsavage, and E. R. Dickstein, University of Florida, Department of Plant Pathology, Gainesville 32611. Plant Dis. 88:85, 2004; published on-line as D-2003-1112-01N, 2004. Accepted for publication 22 Oct 2003.

_Xanthomonas axonopodis_ pv. _vesicatoria_, causal agent of bacterial spot of tomato (_Lycopersicon esculentum_ L.) and sweet pepper (_Capsicum annuum_ L.), was isolated from tomato and pepper plants in
greenhouse production in the Province of Antalya, in southwestern Turkey.

Disease incidence was less than 4 percent of plants observed in 2001 and ranged from 1 to 20 percent in 2002. 11 seedling-producing companies and 26 greenhouses that produce tomato and pepper were surveyed during the rainy seasons of 2001 and 2002. The increase in disease incidence in 2002 is an indication that this disease is
becoming more prevalent on tomato and pepper plants grown in greenhouses in southwestern Turkey.

A gram-negative bacterium producing yellow-pigmented colonies on nutrient agar was consistently isolated from brown, circular spots on leaflets of tomato and sweet pepper seedlings.

5 isolates were pathogenic on commercial cultivars of tomato and pepper when bacterial suspensions (100 million CFU/ml) were infiltrated into the intercellular spaces of leaves to determine race by using procedures described by Bouzar et al. (1). All the isolates produced hypersensitive reaction responses on tomato genotype cv. Hawaii 7998 and pepper genotype cvs. 20 R and 30 R and were designated tomato race 1 pepper race 1 (T1P1) (1).

Fatty acid analysis of the strains identified them as _X. axonopodis vesicatoria_ with similarity index values of 0.872 to 0.933. In addition, the strains were tested with _X. axonopodis vesicatoria_-specific polymerase chain reaction primers (RST 2/3 and RST 9/10) (2). The isolates were determined to be _X. axonopodis vesicatoria_.

Although bacterial spot of tomato has been suspected in Turkey for a number of years, to our knowledge, this is the first report of the bacterium on tomato.

References:
(1) H. Bouzar et al. Phytopathology 84:663, 1994.
(2) R. P. Leite, Jr. et al. Appl. Env. Microbiol. 60:1068, 1994.

[Xanthomonas axonopodis_ pv. _vesicatoria_ [Xav] has been in Turkey for some time. Long-distance spread of the pathogen in the country is likely, mainly by movement of infected or infested tomato seed. The fact that Xav has infected tomato may be the consequence of environmental conditions. Xav is comprised of strains (races) that infect only pepper or tomato, or both crops. - Mod.DH]