Acually mealybug females feed on plant sap, normally in roots or other crevices. They attach themselves to the plant and secrete a powdery wax layer (therefore the name mealybug) used for protection while they suck the plant juices. The males on the other hand, are short-lived as they do not feed at all as adults and only live to fertilize the females. Male citrus mealy bugs fly to the females and resemble fluffy gnats. The most serious pests are mealybugs that feed on citrus; other species damage sugarcane, grapes, pineapple (Jahn et al. 2003), coffee trees, cassava, ferns, cacti and orchids. Mealybugs only tend to be serious pests in the presences of ants because the ants protect them from predators and parasites. Mealybugs also infest some species of carnivorous plant such as Sarracenia (pitcher plants), in such cases it is difficult to eradicate them without repeated applications of insecticide such as diazinon. Small infestations may not inflict significant damage. In larger amounts though, they can induce leaf drop.
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