Race differentiation within strains of Xanthomonas euvesicatoria causal agent of bacterial spot of pepper in Serbia

Abstract

Bacterial spot of pepper, caused by Xanthomonas euvesicatoria regularly causes losses in pepper production in Serbia. During 2008, 2009 and 2010 samples of diseased pepper leaves with bacterial spot symptoms were collected from different localities in Serbia. Total of 116 strains of bacteria were obtained by isolation from infected leaves. Within the world population of the pathogen 11 physiological races are distinguished on the basis of reaction on pepper variety ECW and their isogenic lines known as ECW10R (Bs1 gene), ECW20R (Bs2 gene), ECW30R (Bs3 gene) and PI 235047 (Capsicum pubescens). Race differentiation of Serbian X. euvesicatoria strains was carried out based on the reaction of differential plants. Our studies showed that the population of X. euvesicatoria was heterogeneous, consisting of four physiological races: P1, P3, P7 and P8. The most common was the pepper race P8, followed by P7, P1 and P3 represented by the 93, 17, 5 and 1 strain, respectively.