New Online Help for Managing Whiteflies
Flores August 22, 2007
Tiny, sap-sucking whitefliesand the diseases they often
spreadcause some of the world's worst crop problems and are responsible
for enormous losses every year. Now an online resource has been developed to
help growers afflicted by the pests.
Agricultural Research Service (ARS) scientists in the agency's Subtropical
Insects Research Unit (SIRU),
McKenziein collaboration with the University of Florida, the
University of California, the
University of Georgia,
Texas A & M University and
Cornell University, and endorsed by
industry groups such as the Society of
American Florists, American Nursery &
Landscape Association and the IR-4 Projecthave developed a website
with extensive information about whitefly management. SIRU is part of ARS' U.S.
Research Laboratory in Fort Pierce, Fla.
Whiteflies are found throughout the tropics and subtropics, but can be
troublesome in greenhouses and other growing environments as well. Both
immature and adult stages ingest plant sap and cause damage directly, by
feeding and transmitting plant viruses, or indirectly, by excreting a sticky
substance called honeydew onto leaves and fruit. Sooty mold fungi colonize the
contaminated surfaces, further interfering with photosynthesis and ultimately
resulting in reduced quality of fruit and fiber. In addition to ornamentals,
whiteflies attack cassava, cotton, sweet potato, legumes and many other
vegetables grown in mixed or annual cropping systems.
Called "Management Program for Whiteflies on Propagated Ornamentals
With an Emphasis on the Q-biotype," the comprehensive online resource can be
Among the many topics covered at the website are the importance of
crop hygiene, pre- and post-planting practices and insecticide recommendations.
Also stressed is the need to control whiteflies early, before they spread to
Proper use of insecticides is important for whitefly management,
particularly with respect to avoiding development of insecticide resistance in
whiteflies. The online guide recommends that insecticides be rotated between
chemical classes and should be applied a minimum of two times, at a five- to
seven-day interval, to allow for egg hatch between applications and ensure that
adults, nymphs and newly hatched individuals are all killed.
ARS is the U.S. Department of
Agriculture's chief scientific research agency.