Lexington, Kentucky
February 20, 2006by
Paul Vincelli,
Kentucky Pest News
Anthracnose is a disease of
particular concern on putting greens, as the basal rot phase of
this disease can be extremely destructive to Poa annua
and sometimes to creeping bentgrass. Anthracnose also can be
found on other grasses including Kentucky bluegrass, tall
fescue, and perennial ryegrass, although it is usually not
highly destructive on these hosts under Kentucky conditions.
The fungus that causes anthracnose
in turfgrasses and the one that causes anthracnose of corn have
been, until now, known by the same name: Colletotrichum
graminicola. Corn-infecting strains don’t attack the
turfgrasses, and vice versa. However, because they look so
similar under the microscope, they were considered to be the
same fungal species, and went by the name Colletotrichum
graminicola.
Researchers at
Rutgers University (Drs.
Crouch, Clarke, and Hillman) recently completed an exhaustive
DNA analysis comparing anthracnose-causing fungal isolates from
corn, sorghum, and turfgrasses. Interestingly, their paper,
published last month, reports a very clear distinction between
the turfgrass-infecting strains and those that attack corn.
This DNA-based distinction is so clear-cut that they have
re-named the anthracnose fungus from turfgrass, which is now
known as Colletotrichum cereale.
New taxonomic names like this
eventually come to replace the old names in scientific
communications as well as in trade publications, but the change
doesn’t happen immediately. Thus, you may read about
anthracnose in the future as being caused Colletotrichum
graminicola, or you may read about it being caused by
Colletotrichum cereale. Both names refer to the same
fungus; nothing has changed except the species name. Along
those lines, if a turfgrass fungicide labeled for anthracnose
lists the pathogen name, Colletotrichum graminicola, it
is still legal to use the product as long as the disease
“anthracnose” is listed on the label and all other use
restrictions are followed. |
