Target spot is a polycyclic disease
Target spot disease in tobacco is polycyclic. This means that it can cause many cycles of infections within one growing season. The disease develops best under moderate temperatures, high relative humidity, and prolonged periods of leaf wetness.
Interactive disease cycle
The target spot disease cycle begins at the bottom of the diagram. This is the overwintering, or dormancy, stage of the disease.
Click on the red hotspots to view descriptions and videos of the various stages in the cycle.
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