Aug 20, 2004

Pink Hibiscus Mealybug Threaten Georgia’s CropsSource: Various

The Georgia Department of Agriculture inspectors have been out looking for plants infested with pink hibiscus mealybugs that are a threat to ornamental plants, members of the hibiscus family, peanuts, cotton and okra, which are all major crops in Georgia.

First Foliage Nursery in Homestead, Fla., shipped as many as 44,000 infested hibiscus plants from the beginning of March until the first week of June to 41 Lowe’s and Home Depot stores in Georgia; all but four of the 41 destination stores are in metro Atlanta and North Georgia according to the Georgia Department of Agriculture.

“We can’t afford to have these pests damaging two of our major crops, peanuts and cotton; nor can we afford the potential losses to our $250 million horticulture industry in domestic and foreign markets,” Georgia Department of Agriculture Commissioner Tommy Irvin said.

“This tropical exotic pest came into South Florida about two years ago from the Caribbean,” Irvin said. “These insects are a problem to stop and contain because there is no effective chemical treatment.” In Florida, it was first discovered on the east coast in Broward County in June of 2002.

The most effective action a home or garden owner can take, Irvin suggested, is to double bag the infested plants in black plastic and tie them up securely, then leave them in the hot sun for a minimum of two weeks.

“We’re asking county agents across the state to help us with this problem by assisting local residents with the proper handling of any plants they may have purchased,” Irvin said.

According to the Georgia Department of Agriculture, Georgia is number one in peanut production and number three in cotton produced.

Pink hibiscus mealybugs have become a growing problem in Florida within the last two years a number of efforts are being made to try to fix this problem.

According to the Florida Department of Agriculture and Consumer Services (DOACS), pink hibiscus mealybug is a tiny (3 mm) sap-sucking insect that attacks fruit trees, vegetables and ornamental plants and occurs in most tropical areas of the world. The insect has a life cycle of 24-30 days, and there could be as many as 15 generations each year. Pink hibiscus mealybugs can kill more than 200 plant species, including ornamentals such as chrysanthemums, roses, ginger lily, oleander, palm and hibiscus; food-producing plants such as tomatoes, cucumbers, lettuce, asparagus, cabbage and peppers; and fruit-bearing trees such as oranges, mangos and papayas.

The insect forms colonies on the host plant, which grows into large cotton-like masses of white, waxy deposits on branches and leaves. As it feeds, it pierces into the soft tissues of the plant, injecting a toxic substance that results in malformed leaf and shoot growth (commonly called “bunchy top” ), stunting and possibly death. When fruits are infested, they are covered entirely in the white, waxy coating of the pest. The fruit will either drop off or remain in a dried and shriveled condition. If flower blossoms are attacked, the fruit will set poorly.

In the egg and crawler stages, pink hibiscus mealybug is most easily spread by wind. The wax, which sticks to each egg, can also be transported by ants and other small insects, by a person’s clothing or by an animal’s fur. It can be identified from other mealybug insects by its reddish-brown, smooth body and pink-to-red body fluid. In cooler climates, the pest overwinters on the host plant, either in the egg stage or as an adult. In warmer climates, the insect may stay alive and reproduce year-round.

Currently, biological control is considered the most effective long-term solution to the mealybug infestation. According to the USDA, the parasites are self-perpetuating, persist even when the mealybug is at low population densities, and they continue to attack the mealybug, keeping populations below economic-injury levels.

More information about pink hibiscus mealybugs is available at www.doacs.state.fl.us/pi/enpp/ento/pink.htm and http://creatures.ifas.ufl.edu/orn/mealybug/mealybug.htm.