Lettuce necrotic yellows virus (LNYV)

The virus necrotic yellows lettuce ( Lettuce necrotic yellows virus , LNYV) belongs to the family of Rhabdoviridae and gender cytorhabdovirus (Figure 1). It is transmitted mainly by the garden sow thistle aphid Hyperomyzus lactucae , in the persistent mode. Hyperomyzus carduellinus and Nasonovia ribisnigri are also able to transmit it naturally and artificially, respectively.


- Symptoms

Pale green to chlorotic salads, with a rather flattened shape. Marbling sometimes present on lower leaves. Plants attacked before apple formation may show internal necrotic damage and die. They are also sometimes stunted.


- Main characteristics

This virus shows a very low incidence on lettuce, on which it was first described in Australia in 1963. LNYV, or a similar virus, has been isolated occasionally in New Zealand, but also in Italy, in Spain and Great Britain. Its attacks are found especially in production areas where reservoir weeds are present in large numbers: Sonchus oleraceus , Sonchus hidrophilus ..., this at a time of the year favorable to vectors. It is reported on garlic and on Cicer arietinum . It is not transmitted by the seed.