Monday, December 10, 2007 - 9:05 AM

Aerial dispersal of pink hibiscus mealybug (Hemiptera: Pseudococcidae) in South Florida

Justin Vitullo,, Virginia Polytechnic Institute and State University, Department of Entomology, 216 Price Hall, Blacksburg, VA, Christopher Bergh,, Virginia Polytechnic Institute and State University, Alson H. Smith, Jr. Agricultural Research and Extension Center, 595 Laurel Grove rd, Winchester, VA, Aijun Zhang, Aijun.Zhang@ARS.USDA.GOV, USDA-ARS, Plant Sciences Institute, Invasive Insect Biocontrol and Behavior Laboratory, Bldg. 007, Rm.312, BARC-West, 10300 Baltimore Ave, Beltsville, MD, and Catharine M. Mannion,, University of Florida, Tropical Research and Education Center, 18905 SW 280th Street, Homestead, FL.

The pink hibiscus mealybug (PHM), Maconellicoccus hirsutus (Green), is a highly polyphagous pest and an agricultural threat in the southern USA. Since invading south Florida in 2002, PHM has spread to 36 FL counties and to Louisiana. Although information on its dispersal capabilities is critical toward assisting with predicting, modeling, and managing its spread, very little is know about its natural modes of dispersal on a local scale. To measure aerial dispersal in relation to abiotic factors, potted hibiscus plants heavily infested with PHM were surrounded by sticky traps and monitored at 4-h intervals for seven consecutive days. PHM nymphs were captured in sticky traps and their aerial dispersal exhibited a diel periodicity that peaked between 2 and 6pm and a directionality in accordance with prevailing wind direction. Stepwise and Mallows C(p) linear regressions of abiotic factors showed that wind speed, solar radiation and temperature explained most dispersal. Dispersal was not a function of a single abiotic factor; maximum values did not produce the maximum number of dispersing individuals. To measure the distance of aerial dispersal, potted hibiscus plants heavily infested with PHM were placed upwind from a sticky trap at 1, 5, 10, 25, or 50m and monitored for ten consecutive days. Significantly more PHM were captured at 1m from the plant, although they demonstrated the capacity to disperse up to 50m. Information regarding local dispersal will help optimize biocontrol and monitoring programs, improving our ability to manage the risk associated with this important, invasive pest.

Species 1: Hemiptera Pseudococcidae Maconellicoccus hirsutus (pink hibiscus mealybug)