HOW?
- Mealybug transmits leafroll virus.
- Leafroll reduces yield, grape and wine quality, and it shortens the lifespan of vines.
- We can never win the battle against leafroll disease if we do not deal with mealybug. We have the means and know-how at our disposal.
Mark all mealybug-infested vines now.- Apply contact insecticide with hand lances before budding to target overwintering mealybugs under bark on vine trunks and cordon arms.
- Control ants.
- Monitor mealybug throughout the season.
- Apply systemic or contact insecticides when needed – note withholding periods.
- Only a few infested vines in a block (<2%) – consider biological control.
A protocol for managing mealybug and leafroll is available in a series of user-friendly fact sheets on the IGWS website via http://igws.co.za/content/fact-sheets/leafroll.
For information about registered products for controlling mealybug, contact your local consultant.
– For further information, contact Lucinda Heyns at leheyns@sun.ac.za or Elleunorah Allsopp at allsoppe@arc.agric.za.
