Tomato yellow leaf curl virus (Begomovirus chohini) and tomato chlorosis virus (Crinivirus tomatichlorosis): an emerging threat in tomato production in Georgia, USA

Authors: KUMAR, MANISH - University Of Georgia; AGRWAL, LOKESH - University Of Georgia; BAG, SUDEEP - University Of Georgia; MCAVOY, THEODORE - University Of Georgia; Simmons, Alvin

Submitted to: Plant Health Cases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/11/2026
Publication Date: 7/10/2026
Citation: Kumar, M., Agrwal, L., Bag, S., Mcavoy, T., Simmons, A.M. 2026. Tomato yellow leaf curl virus (Begomovirus chohini) and tomato chlorosis virus (Crinivirus tomatichlorosis): an emerging threat in tomato production in Georgia, USA. Plant Health Cases. https://doi.org/10.1079/planthealthcases.2026.0011.
DOI: https://doi.org/10.1079/planthealthcases.2026.0011

Interpretive Summary: Tomatoes worldwide are significantly threatened by two whitefly-transmitted plant viruses (Tomato yellow leaf curl virus and Tomato chlorosis virus). When these viruses infect plants together, the resulting disease is much more severe and harder to control. This combined infection can even overcome the natural resistance of some tomato cultivars. Including resistant genes from wild tomato into commercial cultivars is helpful, but the resistance can breakdown under mixed infections. Symptoms were seen as early as three to four weeks after the tomatoes were planted in the field, which highlights the need for integrated management approaches for the problem in tomato crops. This research benefits farmers, agricultural industries, and consumers by protecting global tomato production.

Technical Abstract: Tomato yellow leaf curl disease (TYLCD) is a major constraint to tomato (Solanum lycopersicum L.) production globally, threatening yield and sustainability. Although the United States remains a leading producer, national production has declined, with viral diseases playing a significant role. TYLCD is primarily caused by tomato yellow leaf curl virus (TYLCV), a DNA virus transmitted by the sweet potato whitefly. Disease severity is further intensified under mixed infection conditions involving TYLCV and tomato chlorosis virus (ToCV), which can induce severe TYLCD-like symptoms and compromise host resistance. Ty-resistance genes introgressed from wild tomato relatives are deployed in commercial cultivars, providing intermediate resistance; however, resistance is often partial and prone to breakdown, particularly under mixed infections. Notably, severe symptoms were observed as early as three to four weeks post-transplant, well before flowering and fruit set, posing a substantial risk to commercial tomato production. These findings highlight the limitations of current resistance strategies and emphasize the urgent need for integrated management approaches to address evolving virus-vector-host interactions.