Viral Diseases of Canna
Canna yellow mottle virus and canna mosaic virus can be fatal to plants if the proper control methods are not applied
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
We have received several canna samples this spring with symptoms of viral diseases (see images). Canna are susceptible to several viral diseases including canna mosaic virus, canna mottle virus and canna yellow mottle. These viruses persist in the rhizomes throughout dormancy. Thus, plants grown from dividing infected rhizomes will also be infected.
Plants infected with a virus cannot be treated to eradicate the virus. Under good growing conditions, viral symptoms may be less evident, however, the virus is still present. Symptomatic plants should be removed and destroyed.
Symptoms of the viruses often cause streaking and variegation, in some cases the symptoms were thought to be new desirable horticultural characteristics inherent to new cultivars. Since discovering the virus problems some producers have stopped growing some of these cultivars.
Canna mosaic virus causes chlorotic strips between the veins of the foliage. In severe cases, the disease causes stunting and plant death. The disease is vectored by aphids feeding on infected plant material. This virus is also known as bean yellow mosaic. Other hosts include Gladiolus, Lupinus spp. Nicotiana spp. and Petunia spp.
mottle virus and canna yellow mottle viruses cause veinal yellowing,
necrosis and mottling. These viruses affect only canna.
Brunt, A.A., Crabtree, K., Dallwitz, M.J., Gibbs, A.J., Watson, L. and Zurcher, E.J. (eds.) (1996 onwards). `Plant Viruses Online: Descriptions and Lists from the VIDE Database. Version: 20 th August 1996.' URL http://biology.anu.edu.au/Groups/MES/vide/