January 2, 2003
From: EPPO Reporting Service 2003, No.10 [edited]

Details on the situation of tomato chlorosis and tomato infectious chlorosis criniviruses in Spain

In 1997, unusual symptoms were observed on tomato crops in Málaga and Almería in Spain. Symptoms were characterized by interveinal yellowing of leaves and purple discoloration in some cases. The disease was associated with high populations of whiteflies. In 2000, Tomato chlorosis crinivirus (ToCV - EPPO Alert List) was identified as the causal agent. This virus was also found in 2000 in Tenerife and Gran Canaria (Islas Canarias).

In 2001, another virus causing similar symptoms, Tomato infectious chlorosis crinivirus (TICV - EPPO Alert List), was identified on tomato crops in Benicarlo (Castellon). From April 2001 to December 2002, a total of 196 samples of symptomatic tomato plants, collected from the main tomato-growing regions of Spain, were tested by RT-PCR for the presence of ToCV and TICV.

ToCV was detected in 95 samples from: Alicante, Almeria, Castellon, Gran Canaria, Mallorca (Baleares), Murcia, Sevilla, Gran Canaria and Tenerife (Islas Canarias). TICV was detected in 16 tomato samples from Alicante and
Castellon. Both viruses were found in 3 samples from Alicante.

The situation of Tomato chlorosis crinivirus in Spain can be described as follows: Present, found in Andalucia (Almeria, Malaga, Sevilla), Comunidad Valenciana (Alicante, Castellon), Murcia, Islas Baleares (Mallorca), Islas
Canarias (Tenerife, Gran Canaria).

The situation of Tomato infectious chlorosis crinivirus in Spain can be described as follows: Present, found in Comunidad Valenciana (Alicante, Castellon).

Source: Font, M.I.; Vaira, A.M.; Accotto, G.P.; Lacasa, A.; Serra, J.; Gomila, J.; Juarez, M.; Espino, A.I.; Jorda, M.C. (2003) Amarilleos en los cultivos de tomate asociados a Tomato chlorosis virus (ToCV) y Tomato infectious chlorosis virus (TICV) en Espana. Boletin de Sanidad Vegetal, Plagas, 29(1), 110-121.

[Criniviruses are filamentous viruses containing 2 separate genomic segments (650-850 and 700-900 nm), both of which are required for infectivity. Tomato (field and glasshouse) is the main host, but other crops such as potato (_Solanum tuberosum_) and lettuce (_Lactuca sativa_) are susceptible. 2 weed species (Jimson weed, _Datura stramonium_ and Black nightshade, _Solanum nigrum_) are also hosts that may contribute to maintaining these viruses in the wild. TICV is transmitted only by _T. vaporariorum_, but ToCV is transmitted by the greenhouse whitefly (_Trialeurodes vaporariorum_), the banded-wing whitefly (_T. abutilonea_), and by _Bemisia tabaci_ (biotype A) and _B. argentifolii_ (biotype B). Once either virus is established in an agricultural environment containing susceptible hosts, it is very difficult to prevent infection. Disease management requires use of virus-free transplants, avoidance of susceptible hosts (especially weeds), roguing (physical removal) of infected plants, and control of insect vectors by insecticides. - Mod.DH]