Protection Methods
- Curative measures have a very limited impact
Deep plowing can destroy the larvae in the soil. A thorough weeding is also necessary.
Preventive treatment must target the leafhopper, because the curative treatment of phytoplasma is impossible once the plant is infested, similar to viruses. Prevention is the only strategy to limit the development of stolbur in the field.
Active substances are efficient: lambda-cyhalothrin is approved for use against leafhoppers on tobacco
- When should it be treated ?
Recent research on grapevines, where similar problems related to Stolbur (bois Noir) have been encountered, indicates that the first flight of leafhoppers occurs when the sum of air temperatures is around 1026 ° C (sum starting from March 15, and when air temperature is above 6.8 ° C). After observations, and based on the conditions suggested by the research, the flights start around the second half of June. To verify the condition of the sum of temperatures, yellow traps were placed in vineyards.
It seems that the two detection systems of periods when the leafhoppers fly (or move) are in agreement. The yellow trap can be a helpful tool when deciding about an insecticide treatment. Tobacco specific tests are underway.