Anthracnose (blacknose, spadix rot) is caused by the
fungus Colletorichum gloeosporioides and is a common
cause for flower rejection. The fungus is common on numerous
ornamental fruit, and vegetable crops grown in tropical and
subtropical areas. Many specialized strains that differ in
host range are suspected to be included in this large species
group.
The disease primarily affects the individual flowers
on the spadix. Infection starts as a tiny, dark spot that
expands to a triangle or other angular shape depending on
the number and pattern of sepals infected. Each infection
site usually remains isolated, is surrounded by adjacent healthy
tissue, and may be scattered individually or in narrow or
broad zones. Under wet conditions with a high level of inculum,
a general rot of the entire spadix may occur.
The fungus may infect leaves following an injury.
Petioles and pedicels are also susceptible and develop elongated,
diamond - shaped lesions.
The main source of spores is infected anthurium flowers from
within the field. Moisture and temperature have a major influence
on disease influence. Spores are produced in large numbers
and are spread primarily by splashing rain and irrigation
water.
