Lettuce infectious yellows virus (LIYV)

The Infectious by Lettuce infectious yellows virus (LIYV) belongs to the family of Closteroviridae and gender Crinivirus (Figure 1). It is transmitted by Bemisia tabaci in the semi-persistent mode.


- Symptoms

They are characterized by thinning of the veins, yellowing, reddening and curling of the leaves. Plants can remain dwarf. The symptoms are similar to those of BWYV.


- Main characteristics

This other Crinivirus is also mainly reported on lettuce in the United States (California, Arizona) where it was described in 1980. It poses serious problems in the open field in California where infestation rates of 100% and losses of l The order of 50 to 70% is recorded. It is even reported in hydroponic crops in Arizona. This virus is currently in decline due to the disappearance of Bemisia tabaci in the affected regions, to the detriment of Bemisia argentifolia (ineffective vector of this virus). LIYV affects a wide range of cultivated hosts (cotton, cucurbits, beet, carrot ...) and weeds ( Malva spp., Chenopodium spp., Physalis spp., Ipomoea sp., Lactuca canadensis ...). During the season, its vector easily changes from cotton to melon and ends up on lettuce; each time infecting plants.