Canker and
anthracnose generally refer to many different
plant diseases of such broadly similar
symptoms as the appearance of small areas of dead tissue, which grow slowly, often over years. Some are of only minor consequence, but others are ultimately lethal and therefore of major economic importance in
agriculture and
horticulture. Their causes include such a wide range of organisms as
fungi,
bacteria,
mycoplasmas and
viruses. The majority of canker-causing organisms are bound to a unique host
species or
genus, but a few will attack other plants. Weather and animals can spread canker, thereby endangering areas that have only slight amount of canker.