Bemisia tabaci and associated viruses

Bemisia tabaci is an obligate phloem-feeding pest, which is globally distributed. Bemisia tabaci is listed on the EPPO A2 list and EPPO recommends its member countries regulate the pest as quarantine. Only a few EU Member States, (UK, Finland, Ireland, Sweden and certain areas of Portugal) remain free of B. tabaci and maintain ‘Protective Zone’ status against this pest. The cost of maintaining protective zones varies; in Finland, over the period 2000-2007, costs were estimated at €1,261,409, including eradication and monitoring survey costs21. Because B. tabaci is acquiring resistance to pesticides and because of the retrieval of pesticides from the European market, the development of novel control methods for this pest based on biological control agents within EMPHASIS WP3 (predatory bugs, endogenous entomopathogenic fungi) will benefit European agriculture.


In total, at least 120 plant viruses are transmitted by B. tabaci, causing diseases of vegetable and fibre crops worldwide. Tomato (Lycopersicon esculentum) crops are particularly susceptible to more than 50 different species of the Begomovirus genus, including Tomato yellow leaf curl virus (TYLCV) and Tomato yellow leaf curl Sardinia virus (TYLCSV) both of which reduce yields and can cause large economic losses in tomatoes. TLYCV and TYLCSV have been recorded in countries all around the Mediterranean Basin. Other viruses which were determined to be important include: cucurbit yellow stunting disorder virus (CYSDV), which can cause severe losses for cucumber and melon growers, and tomato chlorosis virus (ToCV), which can also affect tomato yields by reducing fruit growth and delaying ripening and more recently Tomato yellow leaf curl virus, TYLCV.

Management approach

For Biological control agents: Screening predatory bugs & mites (Dicyphus tamaninii, Dicyphus errans, Euseius gallicus?) for the management of the pest.). Screen endogenous entomopathogenic fungi (Beauveria bassiana, Paecilomyces fumosoroseus)

Solution proposed by EMPHASIS

For Biological control agents:Report on the most effective BCAs for the management of target pests (PU) and new BC agents available (bugs). Increased efficacy of BCA’s (biorational insecticides to synergise the impact of microbial biopesticides)

Contact person/organisation

Ramon Albajes (UdL) , Maureen Wakefield / Neil Audsley (FERA)