Pink hibiscus mealybug damage

PORT ARANSAS – The pink hibiscus mealybug – which may be of concern to Texas citrus and ornamental industries – has been found near Port Aransas, Texas.

“This mealybug is a potentially serious pest of many ornamental and agricultural crops,” said Dr. Carlos Bogran of College Station, Texas Cooperative Extension entomologist.

First discovered in the U.S. in Florida in 2002, the pink hibiscus mealybug has also been found in California and Louisiana.

It feeds by sucking plant sap from more than 300 species in 74 plant families, Bogran said. Pink hibiscus mealybug adults and nymphs look much like other mealybug species but have some distinguishing characteristics that help in identification.

Adult female (center) pink hibiscus mealybug, next to nymphs and eggs.

Female adults have no wings and have a waxy covering, and adult males are winged and have two long, waxy tails. Females deposit their eggs in waxy egg masses, and young nymphs emerge to find new feeding sites, especially in tender new plant growth, he said. Most other mealybugs have a fringe of wax filaments that surrounds their body, he said.

According to Bogran, pink hibiscus mealybugs disperse in wind currents, by crawling from plant to plant, or by movement of infested plant material or even when stuck on clothing.

Plant symptoms can also be used to help distinguish pink hibiscus mealybug infestations. Feeding causes new leaves to curl; young stems stop elongating and become thick, giving a ‘bunchy-top’ appearance.

Colonies and egg masses are protected by wax accumulations, making the control of the pink hibiscus mealybug with contact insecticides difficult, he said.

“Systemic insecticides may provide some control but are not always effective because eggs and young crawlers can escape exposure,” he said.

“Insecticides are also toxic to natural enemies that help to keep populations under control. Long-term management of this pest will rely on biological control. Two species of parasitic wasps have proven effective in Florida and will also be released in Texas,” he said.

People who suspect a pink hibiscus infestation in their area can go to the University of Florida Web site at http://mrec.ifas.ufl.edu/LSO/PinkMealybug.htm for identification, he said.

If the pink hibiscus mealybug is found, Bogran said, homeowners should avoid using insecticides that may negatively affect beneficial insects, released or naturally occurring.

“Pruning infested plant parts, or sprays consisting of insecticidal soaps and horticultural oils are the best control options for homeowners,” he said.

“Avoid moving infested plants or plant material as it helps the spread of the pest to unaffected areas,” he said.

Dr. Scott Ludwig, entomologist for Texas Cooperative Extension based in Overton, TX, advises homeowners who suspect they have a mealybug infestation to report it. “It is to everyone’s benefit to inform the authorities,” he said.

The Texas Department of Agriculture is working to release beneficial insects in the areas where infestations are confirmed, he said. “They may or may not cut down the infested plants. The release of the beneficial insects could save the homeowners’ and neighbors’ landscape plants.”

“The main thing is that we have good bio-control agents for this pest,” Ludwig said. “Over 90 percent of control is typically achieved when the agents have been released in other areas. I don’t see there being any negative impact on a homeowner for turning in a suspect infection. They (the Texas Department of Agriculture) are just going to confirm the infestation and work with homeowners to manage it.”

According to Bogran, the pink hibiscus mealybug is expected to be most damaging to plants in the subtropical regions of south Texas. “It could pose a threat to garden plants in north Texas,” he said, “especially in the summer months. It’s possible that the mealybug can overwinter in protected parts of outdoor plants including cracks and crevices in the bark, inside fruit bunches or even in the soil.”

“The pink hibiscus mealybug could produce up to 5 generations per year in north Texas as long as temperatures stay at or above 64 degrees,” he said.