Haplotypes of ‘Candidatus Liberibacter solanacearum’ identified in Umbeliferous crops in Spain

Abstract

‘Candidatus Liberibacter solanacearum’ is a phloem-limited Gram-negative bacterium that causes serious damage to different crops of the botanical families Solanaceae and Apiaceae. Five haplotypes have been described: LsoA and LsoB are present in solanaceous crops in America and vectored by the tomato/potato psyllid Bactericera cockerelli; LsoC affects carrots from Northern and Central Europe, and is transmitted by the carrot psyllid Trioza apicalis; haplotypes LsoD and LsoE are present in Southern Europe and Morocco in carrot and celery, and are associated with the psyllid Bactericera trigonica. Thirty-four ‘Ca. L. solanacearum’ isolates were collected in six different regions of Spain from distinct Apiaceae hosts (carrot, celery, parsley and parsnip) in eight consecutive years and were analysed. Their haplotypes were determined by a sequence analysis of 16S ribosomal RNA, the 16S–26S ribosomal RNA intergenic spacer, and the 23S ribosomal RNA and rplJ and rplL genes. Both haplotypes LsoD and LsoE were found across Spain, and no host specificity appeared between these two haplotypes. This is the first report of ‘Ca. L. solanacearum’ associated with parsley and parsnip.