"Candidatus Phytoplasma solani" is a phytopathogenic bacterial Phytoplasma species of the 16SrXII group, the causal agent of the black wood of grapevine. The black wood of grapevine disease is classified as part of the grapevine yellows.
"Ca. Phytoplasma solani" is also associated with the tree peony (Paeonia suffruticosa) yellows disease in China and tobacco (Nicotiana tabacum) leaf abnormality in Turkey.