Phomopsis

There are two Phomopsis diseases that occur in Ontario: Phomopsis seed mould and Phomopsis pod and stem blight.

Phomopsis seed mould is characterized by fine cracks that usually develop near the hilum of the infected seed. A white or grey mould may be visible on the seed surface. The yield, grade, viability and vigour of the seed can be reduced. Yield losses occur because severely infected seeds remain small and light and may be lost during harvest and cleaning operations.

The second phase of the disease is referred to as "pod and stem blight." Although plants are infected early in the season, symptoms do not become apparent until after mid-season. Symptoms on the stems appear as small, black, raised dots or bumps (pycnidia). These bumps are arranged in rows or islands on the stem. On the pods, there are also numerous black dots but they are not arranged in any particular pattern.