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Tim Momol (Plant Pathologist) and Joe Funderburk (Entomologist)
University of Florida, NFREC, 30 Research Road, Quincy, FL 32351
(850) 875-7154
tmomol@ufl.edu
A new disease caused by tomato yellow leaf curl virus (TYLCV) that threatens both commercial tomato production fields and home gardens was identified in southern Florida by Jane Polston (UF/IFAS plant virologist) in July 1997. TYLCV is spread by adult silverleaf whiteflies (Bemisia tabaci Biotype B) (= Bemisia argentifolii). The impact of TYLCV on tomato production can be severe. If plants are infected at an early stage, fruit production will be eliminated and infected plants will be severely stunted. Other symptoms that are typical for this disease are: yellow leaf edges, leaf cupping, reduced leaf size (see Figure) and flower or fruit drop. Identification based only on symptomology is unreliable, because similar symptoms can be caused by other viruses or various growing conditions. Proper identification of TYLCV is available at Plant Disease Clinics in Florida. Send suspected samples through your county Cooperative Extension Service.
Plants with TYLCV-like symptoms were first brought to our attention in October 1998 by Steve Hoak of Glades Crop Care, Inc. Scientists from UF/IFAS (Momol et al.1999, Plant Disease 83:487) confirmed the causal agent as TYLCV in north Florida and south Georgia. During the spring 1999 season a few more plants with TYLCV were detected in north Florida, but whitefly populations were very low.
Growers and consultants are reporting that whitefly populations are higher than usual this summer (1999) in north Florida. Under these conditions growers need to monitor whitefly populations very closely. Silverleaf whiteflies should be controlled according to UF/IFAS Extension recommendations. TYLCV has a broad host range from several plant families. Tobacco is a symptomless host of TYLCV that could be a reservoir host in the southeastern US. Fields and areas around fields should be scouted, and crops and weeds with TYLCV-like symptoms destroyed if possible. Detail information on whitefly identification, monitoring and management is available at the USDA Whitefly Knowledgebase on the WWW at: http://whiteflies.ifas.ufl.edu/).