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story to find out more.
Research leader David Hall
observes ladybugs preying upon pink hibiscus mealybugs. Bottom photo shows
close-up of the female mealybug. Click the images for more information about
them. |
Predatory Insects May Help Solve Mealybug
Problem
By Alfredo Flores April 14, 2005
Agricultural Research Service
(ARS) scientists and cooperators have joined forces to control the pink
hibiscus mealybug, which, if unchecked, could cause an estimated $750 million
in crop losses annually in the United States.
This invasive pest, Maconellicoccus hirsutus, was first found
in Florida several years ago and is spreading within Florida and to other
states. As it feeds, the mealybug injects saliva into the plant, causing
malformation, stunting and eventual death.
Research leader
David
Hall and entomologist
Stephen
Lapointe of the ARS
Subtropical
Insects Research Unit (SIRU), Fort Pierce, Fla., are leading an effort to
find biological methods to stop the pest.
Before the pest came to Florida in 2002, Lapointe, working in St.
Croix, U.S. Virgin Islands, discovered that female pink hibiscus mealybugs
(PMH) emit a powerful pheromone that attracts males. To recreate this chemical
in the laboratory, Lapointe used a hormone analog to eliminate male PHMs from a
colony, leaving only females for pheromone analyses.
He also developed a simple diet for feeding the mealybugs, showing
that PHM could be reared--for research purposes--on an artificial diet. Due to
the expanding infestation of the mealybug, research to develop an optimal
artificial diet was recently initiated at the Fort Pierce laboratory.
In addition to these efforts, the USDA's
Animal and Plant Health Inspection
Service (APHIS) and the Florida
Department of Agriculture and Consumer Services responded to the Florida
infestation by releasing two effective mealybug parasites, Anagyrus kamali
and Gyranusoidea indica, along with a predatory ladybug,
Cryptolaemus montrouzieri. These releases have resulted in a reduction of
more than 98 percent in PHM population density in some locations.
Lapointe's new artificial PHM diet will enable the production of
larger numbers of healthy mealybugs to rear wasps and ladybugs needed for
successful PHM-control programs.
Read more
about the research in the April issue of Agricultural Research magazine.
ARS is the U.S. Department of
Agriculture's chief scientific research agency.