The genus Comandra contains a single species, C. umbellata, with 4 sub-species distributed in North America and the Mediterranean. C. umbellata is considered to be semi-parasitic.
is a small herb that lives as a parasite on plant roots
and has tiny white flowers
is not an obligate parasite
since it obtains nutrition through photosynthesis
, however it does have a wide host range, including, but not limited to many herbs including Aster
, several shrub species Rosa
, and several tree species Acer
, as well as Carex
, and various grasses.
is the alternate host for the rust fungus Cronartium comandrae
Peck., or comandra blister rust, that affects pine
species in North America. Comandra blister rust can cause losses to volume of up to 7% in some regions where it is common.
When Comandra umbellata is infected by Cronartium comandrae basidiospores, yellow blister-like spots bearing urediniospores appear on the leaves of the plant within 20 days. In the following weeks teliospores develop as brown hairlike structures that germinate to produce basidiospores, the Cronartium comandrae life-stage capable of infecting pines.