DETERMINATION OF ALLELIC PROFILE OF Xanthomonas campestris pv. campestris ISOLATES ORIGINATED FROM CABBAGE

Abstract

Cabbage (Brassica oleracea var. capitata L.) is one of the most important vegetable crop in Ser bia, mainly significant for its richness in beneficial nutrients, both minerals and vitamins. Its yield can nowadays be reduced due to presence of many phytopathogens. Xanthomonas campestris pv. camp estris (Xcc), a causal agent of black rot disease, is among the most significant bacteria which affects proper cabbage growth, leading to loss in head weight and quality, therefore drastically reducing its economic value. This pathogen is genetically diverse, which can be seen through the worldwide presence of eleven races and more than thirty combinations of allelic profiles of just four housekeep ing genes - dnaK, fyuA, gyrB, rpoD. The main goal of this work was to subject Xcc isolates originated from cabbage to sequence analysis and to determine their affiliation to certain allelic group. Forty-four Xcc isolates obtained from cabbage in 2014, from five different localities in Serbia (Futog, Temerin, Šabac, Vrnjačka Banja, Čačak), were taken for analysis. DNA of all isolates was first amplified using BOXA1R rep-PCR primer to check if differences in profiles exist. Representative iso lates were then sequenced on the basis of four housekeeping genes (dnaK, fyuA, gyrB, rpoD). Non-re dundatant database (NRDB) from pubMLST (https://pubmlst.org/analysis/nrdb.shtml) was used to determine the allelic profiles for each of the sequenced genes, and to compare tested isolates with already described and deposited strains from NCBI database, whose allelic profiles are known. The results of rep-PCR fingerprinting revealed the same banding patterns for all tested isolates. The allelic profile was 1, 3, 1, 1 for dnaK, fyuA, gyrB and rpoD gene, respectively. This profile coincides with Portuguese B. oleracea Xcc strains CPBF 213, CPBF 1126 (race 6) and CPBF 331 (race 10). The ob tained allelic profile is assigned as sequence type 2 (ST2). In conclusion, since different races can have same allelic profile combinations and vice versa, Xcc race affiliation cannot be determined based on their genetic differences.