This week on IAS spotlight highlights the plant pest Maconellicoccus hirsutus green, the pink hibiscus mealybug. It is a serious plant pest in many subtropical and tropical regions including northern Australia, southeast Asia, and Africa. It attacks many plant species including citrus. The pink hibiscus mealybug doesn’t just attack agricultural plants but ornamental plants in parks and gardens.
The pink hibiscus mealybug lives in colonies and these colonies are usually the host plant they attach themselves to, to hide away from predators. The main agent of dispersal to plants is the juveniles. The nymphs have little wax and can survive without food for two days and are easily dispersed by wind. The mealybug can be found on the leaves, buds, fruit, stems, and roots of many plants. On the hibiscus plant, the mealybug infests young twigs, causing deformed leaves, thickened twigs, and deformed terminal growth due to the shortening of the internodes.
It feeds on the soft tissues of many plant species, injecting toxic saliva into the plants that contort and curl the leaves. Stems may twist and buds may not flower, fruits may also be abnormal. The shoot tips of plants may develop a bushy appearance and may become stunted. The honeydew that the mealybug excretes encourages the development of black sooty mold and high infestations kill plants. The hibiscus mealybug may stunt the growth of young plants through heavy infestations. Research has found that accidental introduction of this species into new territories is possible through the movement of live plant material via air transport/mail or shipping, cut flowers, ornamental plants, fruit, and vegetative and vegetable propagules.
Subsequently, managing the pink hibiscus mealybug involves its natural enemy, the wasp. The biological control agent, Anagyrus Kamali, is a non-stinging species of wasp used for new areas of infestation and has been an effective form of biological control. On Caribbean islands, this parasitoid has been released with successful results in controlling infestations.
For more management methods, read more from our sources below!
Entomology & Nematology/ UF-IFAS – Pink hibiscus mealybug
CABI – Pink Hibiscus Mealybug
ID Tools – Pink Hibiscus Mealybug
UWI – Maconellicoccus hirsutus (Hibiscus Mealybug)