Phylogenetic diversity of Clavibacter michiganensis subsp. michiganensis isolates causing bacterial canker of tomato in Greece

Abstract Tomato bacterial canker, caused by Clavibacter michiganensis subsp. ( Cmm ) (Li et al. 2018), is a common destructive disease worldwide. The bacterium colonizes plant’s vascular system causing characteristic symptoms such as wilting, cankers, brown and black discoloration of vessels, white spots on the fruit leaves. In present work, isolates were collected from infected tomato plants 11 Greek Prefectures during years 2003-2018, genetic variability was investigated. After initial identification, 93 selected strains subjected to phylogenetic analyses based sequencing multiple loci (Multi-Locus Sequencing Analysis, MLSA) utilizing four housekeeping genes atpD , ppk kdpA sdhA ). MLSA highlighted 4.1% in nucleotide sequences classified into 38 haplotypes. Nevertheless, grouping not accordance with geographical distribution, fact that probably advocates introduction propagating material. However, isolated same area different year placed group which means pathogen can remain active between growing seasons. study provides important epidemiological information outbreaks spread Greece.