Allelic profi le of Serbian Xanthomonas campestris pv. campestris isolates from cabbage

Abstract

Xanthomonas campestris pv. campestris (Xcc), the causal agent of black rot disease of cabbage (Brassica oleracea var. capitata L.), is one of the most important bacteria which aff ect proper cabbage growth, leading to head weight and quality losses and thereby drastically reducing its marketing value. The pathogen is genetically diverse, which is evident from the presence of eleven races worldwide and more than thirty combinations of allelic profi les. Therefore, this study aimed to determine the allelic profi les of Serbian cabbage Xcc strains obtained in 2014. The analysis was done on three selected Xcc strains whose DNA was fi rst amplifi ed using polymerase chain reaction (PCR) with four housekeeping genes – P-X dnaK, fyuA, gyrB, and rpoD, then sequenced, and the obtained sequences were fi nally used to determine allelic profi les. Allelic profi les were determined by comparison with 33 Xcc strains obtained from diff erent hosts and regions, whose allelic profi les had been determined previously. A non-redundant database (NRDB) from the pubMLST was used for allelic profi le determination and Phyloviz software for constructing a minimum spanning tree. The obtained allelic profi le of all Serbian Xcc cabbage strains was 1, 3, 1, 1 for the P-X-dnaK, fyuA, gyrB and rpoD genes, respectively. This profi le is assigned as sequence type 2 (ST2) and it coincides with a Portuguese B. oleracea Xcc strain, CPBF 213, originating from B. oleracea var. costata. No connection between sequence type (ST) and the host was detected.