
Tomato Foe
Attacks Other Crops, TooBy Alfredo Flores January 31, 2003Tomato spotted wilt virus (TSWV) is
estimated to cause more than $1 billion in damage to crops throughout the world
annually. As its name implies, TSWV was originally observed in tomatoes. But in recent
years, there have been reports of a sharp increase in TSWV attacking not only
tomatoes, but also peppers and peanuts, particularly in Florida, Georgia and
North Carolina. Last year Virginia saw a tremendous increase in TSWV problems
in potatoes. In May 2002, Agricultural Research
Service plant pathologist Scott T. Adkins, in conjunction with the
University of Florida (UF), began to study
crop damage caused by this virus in the tomato production areas of northwest
Florida, just west of Tallahassee. He and his team observed, in adjacent tomato
and pepper fields, a high percentage of infected tomato plants, but a low
percentage of infected pepper plants. Adkins took TSWV samplings from tomato and pepper plants back for analysis
by scientists in ARS'
Subtropical Plant
Pathology Research Unit at Ft. Pierce, Fla. He is trying to see if one host
(tomato) is affecting the ability of TSWV to infect the other host (pepper) and
vice versa. The virus can turn leaves brown, purple or bronze and frequently kills the
plants' stem tips. It can also cause brown or yellow spots and rings on
tomatoes and other produce, making them unappealing to consumers and therefore
unmarketable. TSWV is transmitted from plant to plant almost exclusively by several
species of thrips. The western flower thrips (Frankliniella
occidentalis) and the tobacco thrips (F. fusca) are major vector
species in Florida, although F. bispinosa may also be a locally
important vector. Adkins is working closely with UF plant pathologist Tim Momol, who is
located at the North Florida Research and
Education Center in Quincy. Southeastern produce growers are showing great
interest in their work. Adkins hopes to characterize the diversity of the virus across the wide
range of host plants TSWV infects, not only in the region, but also throughout
the United States. Once this is determined, he can use the information to
develop improved virus management strategies and crop cultivars that will
resist infection. ARS is the U.S. Department of
Agriculture's principal scientific research agency. U.S. Department of Agriculture |