Lettuce big-vein disease causes leaf distortion and ruffling in affected

lettuce Lettuce (''Lactuca sativa'') is an annual plant of the family Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds. Lettuce is most often used for salads, although it is also seen in other kinds of food, ...

plants. This disease was first associated in 1983 with a rod-shaped

virus A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1 ...

named

lettuce big-vein associated virus Lettuce (''Lactuca sativa'') is an annual plant of the family Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds. Lettuce is most often used for salads, although it is also seen in other kinds of food, ...

(LBVaV), which is transmitted by the obligately

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has c ...

soil-inhabiting

fungus A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...

, ''

Olpidium brassicae ''Olpidium brassicae'' is a plant pathogen, it is a fungal obligate parasite. In 1983, the Alsike, Alberta area's clover (which is a major part of horses' diet) was struck by a fungus epidemic of ''Olpidium brassicae'', previously not seen in Ca ...

''. However, in 2000, a second virus, ''

Mirafiori lettuce virus The Stabilimento di Mirafiori (in English, the Mirafiori Factory) is the headquarters and industrial district of the Italian automobile manufacturer Fiat, a subsidiary of FCA Italy, which is part of Stellantis, and is the headquarters of CNH Ind ...

'', was found in lettuce showing big-vein symptoms. Furthermore, since the lettuce infected with this virus alone developed big-vein symptoms, it is considered to be a main agent of the big-vein disease.

Symptoms

Affected plants have veins that become large and clear, causing the rest of the leaf to become ruffled. Severely infected plants may fail to form a lettuce head.

Control

* Grow disease-resistant

cultivar A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, ...

s. * Use disease-free healthy seeds. * Treat with

methyl bromide Bromomethane, commonly known as methyl bromide, is an organobromine compound with formula C H3 Br. This colorless, odorless, nonflammable gas is produced both industrially and biologically. It has a tetrahedral shape and it is a recognized ozon ...

chloropicrin Chloropicrin, also known as PS and nitrochloroform, is a chemical compound currently used as a broad-spectrum antimicrobial, fungicide, herbicide, insecticide, and nematicide. It was used as a poison gas in World War I. Its chemical structural for ...

, or

dazomet Dazomet is a common soil fumigant that acts as a herbicide, fungicide, slimicide, and nematicide. Applications Dazomet is a chemical used to kill pests that inhibit plant growth through gaseous degradation. Dazomet is used as a soil sterilant o ...

solution.

References

Lettuce diseases Viral plant pathogens and diseases Leaf diseases Rhabdoviridae {{Virus-plant-disease-stub