Stunt is a virus-like disease mainly
present in eastern North America.
Symptoms
Infected bushes are severely stunted and
branches appear bushy because of shortened internodes. Leaves
are cupped slightly downward and may also have chlorotic
areas that turn red in fall.
Short bushy growth at base of infected bush.
Disease cycle
The stunt phytoplasma is a microorganism that inhabits
the sapwood and is vectored by sharp-nosed leafhoppers (Scaphytopius
spp.). Infections coincide with peaks in leafhopper activity and
become systemic. Plants are infected for life.
Left, stunt causes leaf cupping and interveinal chlorosis. Right, a stunted bush (left) next to a healthy bush.
Management
Plant virus-tested, clean planting stock; remove
and destroy infected plants; monitor leafhoppers and apply well-timed
insecticides.