Poster: Biology & Disease Mgmt: Integrated Pest Mgmt
419-P
Management of Tomato chlorotic spot virus, an emerging tospovirus of tomato causing severe losses in south Florida
S. ZHANG (1), Y. Fu (2), X. Fan (2), D. Seal (2), Q. Wang (3), E. McAvoy (4) (1) Tropical Research and Education Center, University of Florida, IFAS, U.S.A.; (2) Tropical Research and Education Center, University of Florida, IFAS, U.S.A.; (3) UF/IFAS Miam
Tomato chlorotic spot virus (TCSV) is a devastating tospovirus transmitted by thrips. TCSV was first reported in the USA from tomato plants in Homestead, FL in 2012. Outbreaks of TCSV in Homestead area since 2014 have caused significant losses to growers. TCSV has become established in south Florida and it occurs more widely with greater frequency across this region, bringing a serious concern that TCSV may spread to other tomato production regions. Field trials have conducted in Homestead since 2015 to develop management strategies for TCSV. Fourteen tomato varieties resistant to Tomato spotted wilt virus (TSWV) were evaluated. In the spring trial in 2015, all tested varieties exhibited varying levels of resistance to TCSV (10-40% vs 100% infection in the commercial standard cv. ‘FL 47’) two months after transplanting. In the two repeated trials carried out in the fall of 2015, all these varieties had lower than 8% disease incidence 16 weeks after transplanting, whereas 50% plants of cv. ‘FL 47’ showed TCSV symptoms. In an insecticide trial conducted in the spring of 2015, only spinetoram (Radiant®) and cyantraniliprole (Exirel®) significantly (P<0.05) reduced TCSV incidence compared to the untreated control. In the fall trials of 2015, plant activator acibenzolar-S-methyl (Actigard®) numerically reduced TCSV incidence. The use of metalized UV-reflective plastic mulch failed to suppress the disease. Results from this study will be reported and discussed in detail.