TSWV
scouted June 4, 2026
- Scientific Name
- Tomato spotted wilt virus
- Background
- A 5-6 week-old dark tobacco field, variety Narrow leaf madole, was being scouted, and it was observed that 1% of the field was affected by disking in the pith, and plants were flopped with lesions at ground level. A sample was submitted to the PDIC for diagnosis.
- Conclusion
- The issue was identified as Tomato Spotted Wilt Virus (TSWV) on tobacco. This disease is caused by a virus in the Orthotospovirus genus and is transmitted by thrips, primarily tobacco thrips (Frankliniella fusca) and western flower thrips (F. occidentalis). Not all infected tobacco plants develop symptoms, and severity can range from mild to severe. Symptoms typically appear 2 to 3 weeks after infection which makes early detection difficult. Common symptoms include necrotic spots and concentric rings that initially appear yellow and later turn brown. There is no cure for TSWV but reducing thrips populations through chemical and cultural practices can help limit disease spread.
- Resources