Cotton mealybug
Cotton mealybug is a pest derived from small biting / sucking insects (Planococcus citri [Risso]) that can attack several of the grapevine's organs. These insects are homopterous and have six generations per year. They hibernate in old wood or under the vine’s rhytidome. After hibernation, the insects begin to colonise nodes, internodes, petioles and ribs. The cotton mealybug larvae absorb the plant’s sap and the plant ends up drying.
- Perishing of the grapevine - Appearance of sooty mould (dark-coloured fungus that is found in the honeydew produced by the cotton mealybug) - Appearance of ants due to the presence of honeydew - White formations - resembling cotton flocks - in the rods, bunch and leaves - Honeydew on the bunches (end of July)
Cultural control:
Clean the grapevine’s trunk and thicker bunches, removing the rhytidome in the affected areas.
Chemical control:
Winter Treatment:
- summer oil
Spring / Summer Treatment:
- chlorpyrifos - malathion + mineral oil - methidathion
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