Origin:
Currently found in both Europe and North America, and known from Europe 50 years prior to its discovery in the U.S., so possibly European in origin.
Biology:
Two forms of this serious pest occur, one that attacks the roots of plants and one that attacks the foliage. When the roots are attacked it encourages a crusty growth of fungus that the mealybugs may be living under, and root attack can kill the roots and cause death of the plant. The insect is a vector of some plant pathogens. The female deposits eggs in clumps and covers them with a waxy film, laying an average of 300 eggs in her lifetime. Eggs hatch in 2-10 days. Males undergo 4 instars, and develop to a winged adult is just over 3 weeks. Females go through 3 instar stages, and become the non-winged adult in about 4 weeks. Females live an average of 3 months, while males live only a few days. This species is a pest of many agricultural crops, including cocoa, coffee, citrus, banana, mango, and other regional food crops. It also is a pest on ornamental plants when present in warm, humid conditions, such as in greenhouses or areas of the country that are not overly dry and cold.
Identification:
Females and nymphs will be most obvious on plants. The adult female is about 3 mm long, oval and flattened, and covered with a white powdery wax. Short waxy filaments protrude from the sides of the insect.
Characteristicts Important to Control:
Where natural predators are active the insect may be kept under control. Chemical controls are difficult, but include horticultural oils, often mixed with a contact insecticide. A systemic applied to the soil, such as imidacloprid, can be effective and provide long-term presence of the a.i. in the foliage. Removal of infested plants or plant parts also can be an easy and effective control, but it may be difficult to locate all of the immatures on the plant. Nymphs and adult females are highly mobile.
