Hosts and symptoms
Tobacco necrosis virus (TNV) can thrive on a handful of viable hosts. These hosts include tobacco, zucchini, cucumbers, carrots, French bean, tomatoes, potatoes, and tulips. There are a variety of symptoms that are dependent on the host species. In infected plants, abnormal coloring or necrotic tissue in the leaves may occur and roots may have lesions. If bark is present on the plant, it may become discolored. Fruit or tubers can become covered with sunken and discolored spots and can be smaller overall. On a whole-plant scale, damping off or early dying may occur.Management
Currently, there is not a way to chemically control tobacco necrosis virus. There are, however, cultural management options to reduce the risk of the virus. Prior to planting, one can reduce risk of this disease by investigating the history of their soil for past presence of TNV or of its fungal host vector ''Importance
While tobacco necrosis virus can infect many crops, it has a small economic impact relative to other plant pathogens. It is not commonly occurring or widespread in crops and does not have as severe of an effect on a crop as other, more important pathogens. TNV has many unusual and uncommon features when compared to other viruses, and therefore has some scientific importance. For example, TNV has a high level of resistance to heat and chemical agents as well as to degradation due to aging. TNV is also unusual in that it can be spread via a fungus (''Olpidium brassicae'') for some hosts and in some environments and also in that it can be both air- and water-borne.References
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