Gallup, C.A., M.J. Sullivan, and H.D. Shew. 2006. Black Shank of Tobacco. The Plant Health Instructor. DOI: 10.1094/PHI-I-2006-0717-01

DISEASE:  Black Shank of Tobacco

PATHOGEN:  Phytophthora nicotianae Breda de Haan (synonyms: Phytophthora parasitica var. nicotianae, Phytophthora nicotianae var. nicotianae).

HOSTS: Tobacco: Nicotiana tabacum and N. rustica

Cultivated tobaccos are primarily in the species N. tabacum, with a small amount of commercial tobacco coming from N. rustica. Within N. tabacum, multiple types of tobacco are grown, including flue-cured, light air-cured (primarily burley and Maryland types), oriental, dark air-cured (includes cigar types), and dark fire-cured. Infection of the roots of numerous other plants has been reported, but tobacco isolates appear to be host specific.

Authors:
Courtney A. Gallup, Melinda J. Sullivan, and H. David Shew
North Carolina State University

Black shank can be a devastating root and crown rot disease of all types of tobacco, with losses in individual fields reaching 100%. The disease was first described from Indonesia in 1896, but has since spread to most major tobacco growing areas worldwide. Management requires an integrated approach based on cultural practices, host resistance, and soil applied fungicides.

Symptoms of black shank on flue-cured tobacco with characteristic yellowing and wilting of leaves.