Black wood (Bois noir) (Candidatus Phytoplasma solani-related) is a phytoplasm of grape, corn, and solenaceous hosts. It is a native of Europe.
The reservoirs for the disease are stinging nettle and bindweed. Insect vectors are infected by the phytoplasm upon feeding on these reservoirs. Various crops and plants can become infected, with most displaying symptoms of leaf yellowing and curling. Corn plants commonly become red as infections develop.