Verticillium wilt—Verticillium dahliae and
Verticillium wilt affects many herbaceous plants, including
dahlia, gerbera, marigold, peony, snapdragon, and vinca.
Leaves infected with Verticillium wilt
and turn yellow, first at the margins and between veins;
foliage then turns tan or brown and dies, progressing upwards
from the base to the tip of the plant or branch. Browning
of older leaves while younger leaves remain green is also
plants are often affected first on one side of the plant
or only in scattered portions of the canopy. Water-conducting
tissue in branches and stems may darken in some hosts. Infection
usually occurs during cool conditions but damage may not
become apparent until warm weather when plants are more stressed.
Sanitation and resistant
plants are the primary strategies for managing Verticillium wilt. Plant only pathogen-free plants. Avoid planting susceptible cultivars. Plant in disease-free soil. Solarization can reduce Verticillium fungi in the upper few inches of soil. Keep plants vigorous by providing proper cultural care.
Maple foliage damaged by Verticillium wilt