Leaves of infected plants are small and curl upward; and show strong crumpling and interveinal and marginal yellowing. The internodes of infected plants become shortened and, together with the stunted growth, plants often take on a bushy appearance, which is sometimes referred to as "bonsai" or broccoli'-like growth. Flowers formed on infected plants commonly do not develop and fall off (abscise). Fruit production is dramatically reduced, particularly when plants are infected at an early age, and it is not uncommon for losses of 100% to be experienced in fields with heavily infected plants.
Tomato leaf curl disease is not transmitted in seed, soil or from plant to plant by handling. It is harboured in infected host plants, some of which may be hosts that do not show symptoms. The virus causing tomato leaf curl disease is spread from plant to plant by silverleaf whitefly (SLW) (the biotype B of Bemisia tabaci). SLW is a serious pest in tomatoes and other vegetable crops in the coastal and some inland areas of Queensland and New South Wales. It is an established pest in Western Australia and cotton production systems in Queensland.
