Nandina mosaic viruses
In California, at least two viruses occur in heavenly bamboo, Nandina domestica. The Cucumber mosaic virus and Plantago asiatica mosaic virus (formerly Nandina mosaic virus) mostly cause a mottled red discoloration of heavenly bamboo leaves.
Identification
Leaf reddening in heavenly bamboo can also be due to other causes such as high light intensity.
Cucumber mosaic virus infection causes wine red discoloration of new spring growth in nandina. Leaves may be thinner (more narrow in width) than normal and cupped downward. There may be fewer flower buds and berries on infected plants.
Plantago asiatica mosaic virus causes a relatively mild mosaic; the reddening of foliage may not be very intense or extensive. There may be stunting and leaf distortion of infected Nandina.
Life cycle
Plantago asiatica mosaic virus spreads mechanically during propagation and pruning. The virus can be introduced into plants on cutting tools contaminated with sap from an infected plant.
Cucumber mosaic virus, infects a variety of agricultural and ornamental plants and annual and perennial weeds. It can be transmitted mechanically. In the field, Cucumber mosaic virus is often spread by aphids, especially the melon aphid, Aphis gossypii, and green peach aphid, Myzus persicae. Aphids acquire the virus while feeding on infected plants and transmit it when they move and feed on other plants. Once a plant becomes infected with the virus, it usually remains infected throughout its life.
Solutions
There is no cure or treatment for virus-infected plants in landscapes. Replace affected plants if their performance is unsatisfactory. Purchase and plant only Nandina that has been virus-tested and found to be free of all known viruses. For more information, see Viruses.
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