Dr. Christine Casey, North Carolina State University, $12,500, 3 year project 
 

Executive Summary
The tospoviruses are a group of plant-infecting viruses that are transmitted by several species of thrips.  These insects are small, highly mobile, and distributed worldwide.  This virus group causes one of the most serious disease problems in agriculture.
 

Tospovirus management in flower crops is complicated by several factors.  Disease incidence does not correspond to thrips density, so merely monitoring insect populations is not sufficient to predict epidemics. Virus symptoms are variable and mimic other diseases or nutritional disorders, and symptoms may not appear on infected plants for 10 to 14 days after thrips feeding.  Finally, weeds in and around the production area can be asymptomatic virus sources. A priority for improved  tospovirus management is an early warning system such as indicator plants that would alert growers to the presence of infected thrips before crop symptoms are seen. Previous research funded by the American Floral Endowment showed the value of indicator plants as a tool to locate sources of virus-carrying thrips, but did not address the essential question of whether indicator plants are more attractive to these thrips than the crops they are intended to protect.
 

It is also important to consider the role of the crop plants themselves in virus epidemics. Certain infected crops may serve as sources for the spread of tospovirus epidemics if they are more attractive to thrips than other crops.  If this information were available these plants could be a priority for culling.