Molecular variation of ‘Candidatus Phytoplasma ziziphi’ isolated during co-cultivation from micropropagated jujube witches’ broom infected shoots

The aim of the study was to isolate and cultivate ‘Candidatus Phytoplasma ziziphi’ (16SrV-B) from micropropagated jujube shoots exhibiting witches’ broom symptoms. As a result, liquid cultures containing ‘Ca. P. ziziphi’ along with at least one bacterial species, Pseudomonas, were obtained. Subsequently, colonies were grown on solid agar media, in which the presence of ‘Ca. P. ziziphi’ alongside the predominant Pseudomonas species was confirmed using PCR methods. It was found that over time, the phytoplasma cell cultures tends to accumulate DNA changes that significantly distinguish them from the original isolate. It is possible that these variations may provide advantages to particular phytoplasma strains allowing them to more efficiently multiply in artificial nutrient media.