Thrips and Tomato Spotted Wilt Management in Tomato and Pepper

Summary

The management of thrips vectored TSWV has been progressing in the area of host plant resistance in recent years. Ranking of commercially available TSWV-resistant cultivars of tomato and pepper are provided.

Situation

Thrips-vectored Tomato Spotted Wilt Virus (TSWV), of the genus Tospovirus (Family Bunyaviridae), is one of the major factors contributing to yield loss in pepper and tomato. In Georgia, TSWV reduces pepper yields by an estimated 1-5% annually. In 2005, the Georgia pepper crop, was valued at $87 million and tomato was valued at $81 million. TSWV is primarily transmitted by western flower thrips, Frankliniella occidentalis (Pergande), and tobacco thrips, F. fusca (Hinds). Incidence of TSWV varies from year to year; however, it is not uncommon for disease incidence to exceed 20% infection in years with higher disease incidence. TSWV detection in winter weeds in south Georgia suggested that 2006 would exhibit late but higher TSWV than the previous two years and in fact it was higher.

Response

The goal of this project was to demonstrate the impact of TSWV-resistant tomato and pepper on yields in the presence of high levels of thrips vectors of TSWV. Seed of commercially available cultivars of TSWV-resistant peppers and tomato were acquired and planted in a greenhouse at the Coastal Plain Experiment Station using standard seedling production practices. One month old seedlings were transplanted into plastic mulched, methyl bromide fumigated beds at the Tifton Vegetable Park. Plants were monitored for TSWV symptoms and the presence of thrips vectors. Yield and fruit quality were evaluated for the impact of TSWV on fruit quality. Plots were viewed by participants at a UGA vegetable field day in May 2006.

Impact

Results from the TSWV-resistant pepper and tomato cultivar test are summarized here as the 05/25/06 percentage TSWV symptomatic plants. These data rank the cultivars which the company designates as either Resistant(R)/Susceptible(S)in terms of overall resistance in the following lists. Pepper TSWV Host Plant Resistance Trial Cultivar Company % TSWV groups Stiletto Syngenta R 0% c Heritage Harris Moran R 0% c Magico Harris Moran R 0% c Plato Seminis R 0% c Aristotle Seminis S 23% b Excursion II Abbott & Cobb R 40% b Revolution Harris Moran S 63% a Tomato TSWV Host Plant Resistance Trial Cultivar Company % TSWV groups Amelia Harris Moran R 0% d Quincy Seminis R 0% d BHN 685 BHN (Siegers) R 0% d Bella Rosa Sakata(Siegers) R 3% d Talladega Syngenta R 3% d HAZ 3074 Hazera (Siegers) R 3% d BHN 444 BHN (Siegers) R 7% cd BHN 640 BHN (Siegers) R 7% cd Crista Harris Moran R 7% cd Muriel Sakata(Siegers) R 10% cd Cupid Seminis S 23% cd BHN 602 BHN (Siegers) R 33% bc Caporal Vilmorin(Clifton) R 53% ab Mariana Sakata(Rupp) S 70% ab FL 47 Seminis (Siegers) S 77% a Marglobe USDA S 80% a These results clearly indicate that some cultivars are much more tolerant to TSWV under field conditions and provide a viable means of managing this serious pest problem in commercial production systems. These tests will be repeated in 2007.

State Issue

Agricultural Profitability and Sustainability

Details

• Year: 2006
• Geographic Scope: State
• County: Tift
• Program Areas:
  • Agriculture & Natural Resources