Hemp Leaf Spot (Bipolaris Leaf Spot or Zonate Leaf Spot): Caused by Bipolaris gigantea, this disease produces circular spots with white centers that often fall out. While the spots remain small, they may coalesce, leading to leaf blighting. All leaf tissue is susceptible to infection. Severe losses have been reported in a limited number of floral hemp cultivars, although most cultivars exhibit slight to moderate susceptibility. The host range includes several gramineous hosts and a small number of broadleaf weed species.
