Occurrence of Pseudomonas syringae pv. tomato in Bulgaria

Abstract. Bacterial speck of tomato caused by Pseudomonas syringae pv. tomato is an important disease in many tomato growing areas. The pathogen is known to comprise two races – R0 and R1. Sixty-seven pathogenic strains isolated in the period 2000 – 2013 from tomatoes with symptoms of bacterial speck in Bulgaria were the object of this study. The isolates were identified as P. syringae pv. tomato by the miniaturized Biolog system and possess the typical metabolic profile for the species. The pathogenic population of P. syringae pv. tomato in Bulgaria is homogeneous by phenotypic characteristics. The races of the strains were determined. On the base of the obtained results and the data available in the literature for the country, the proportions of the occurrence of the two races since 1985 alter cyclically with a tendency for shortening the cycle. The changes in the spread and development of the disease are related to the climatic changes

Variability in the resistance to bacterial spot causal agents Xanthomonas euvesicatoria P and Xanthomonas vesicatoria PT2 among Bulgarian and introduced pepper varieties

Abstract. Bacterial spot in pepper (Capsicum annuum L.) is caused by Xanthomonas euvesicatoria and X. vesicatoria. The natural Bulgarian population of X. vesicatoria belongs to pepper-tomato pathotypes (PT), whereas Macedonian population of X. euvesicatoria refers to pepper pathotypes (P). Bacterial spot of pepper caused by X. vesicatoria and X. euvesicatoria has become a very serious disease in Bulgaria during the past few years. The use of resistant pepper cultivars is the most economically and technically efficient method for control. Pepper varieties with immune and/or resistant reaction were not found in this study. Moderately susceptible to both pathogens were the following varieties: Kapia UV-Vertus, Sofijska kapia and Familiya of Kapia type, Quadrato D"Asti Giallo of Dolma type and Chorbadzhiyski of long pungent fruits. All varieties with cone-shaped fruits and the ones for sweet powder performed with highly susceptible reaction to X. еuvesicatoria