Tomato yellow leaf curl virus
Tomato yellow leaf curl virus (TYLCV) can infect over 30 different kinds of plants, but it's mainly known to cause devastating losses up to 99 per cent in the yield of tomatoes.
TYLCV, a begomovirus, was first detected in Australia in early 2006 in Brisbane on cherry tomatoes and in Bundaberg in both commercial and home garden tomatoes. TYLCV is also present in the Northern Territory.
Symptoms of TYLCV
The most obvious symptoms in tomato plants are small leaves that become yellow between the veins. The leaves also curl upwards and towards the middle of the leaf (Figure 1).
In seedlings, the shoots become shortened and give the young plants a bushy appearance. Also, although tomato production is reduced by infection, the fruit appears unaffected.
Spread by silverleaf whitefly
TYLCV can be transmitted from diseased to healthy plants by silverleaf whitefly (Bemisia tabaci), which feeds on a wide range of hosts (Figure 2). The virus is not known to be seedborne or to be transmitted mechanically.
Following recent detections, silverleaf whitefly is now considered established in Victoria.
CABI, 2021, Tomato yellow leaf curl virus (leaf curl), Invasive Species Compendium, Wallingford, UK: CAB International
Figure 1 John Thomas, Queensland Department of Industries and Fisheries
Figure 2 W. Billen, Pflanzenbeschaustelle, Weil am Rhein, Bugwood.org