Visual inspections of elm trees in south Moravia in 1997-2007 revealed a rare occurrence of plants with smaller and cowl-forming leaves on some twigs, i.e. a feature resembling witches'-broom disease observed on the end of twigs. The presence of phytoplasma-like bodies was observed by transmission electron microscopy of phloem tissue. On the other hand, no phytoplasmas were found in asymptomatic trees. Nucleic acids extracted from these plants were used in nested-PCR assays with primers amplifying 16S rRNA sequences specific for phytoplasmas. Sequence analyses of the 16S-23S ribosomal operon (1852 bp) allowed for the classification of the detected phytoplasmas in the elm yellows group, but its position remained on the boundary of the 16SrV-A and 16SrV-C ribosomal subgroups. Sequence analyses of the ribosomal protein of the rpl22-rps3 and secY genes lead to further classification and revealed the phytoplasmas' affiliations to the 'Candidates Phytoplasma ulmi'. Some exceptions in unique oligonucleotide sequences defined for 'Ca. Phytoplasma ulmi' were found in the Czech isolate. This is the northernmost confirmed occurrence of phytoplasma on elm trees within Europe.

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Lilium martagon (Turk's-cap lily) found in West Bohemia showed untisual malformation in the shape of a very flattened stem. Scanning electron microscopy (SEM) and fluorescence microscopy (DAPI staining) revealed phytoplasma bodies in sieve tube elements of the diseased plant, but not in healthy ones. The diameter of the bodies ranged from 100 to 900 nm, with an average of 400 nm. Phytoplastna 16S rDNA detection by nested PCR resulted in 1.1 kbp product. Based on restriction analysis of amplified region, this phytoplasma is classified to the aster yellows cluster (16SrI), subgroup 1-C, with clover phyilody phytoplasma as a type strain. Partial phytoplasma 16S rDNA sequence amplified by nested PCR was compared through restriction fragment length polymorphism. No virus infection was detected. This paper is the first report on clover phyilody phytoplasma in a monocotyledonous host identified on molecular level.