Agriculture Reference
In-Depth Information
Symptoms
The fingertips below the f flower are blackened. The surface
of the rotted tip is irregular and often covered with fungal
growth if humidity is high. Black tip does not have the
ashy-grey appearance of cigar end.
Source of infection and spread
The fungus is a common inhabitant of dead f flower parts
and leaves. Spores of the fungus are produced during wet
weather and infect fruit where tips have been injured or
damaged by sunburn.
Fig 5.19 A hand of fruit affected by
Ceratocystis
fruit rot.
Importance
Black tip is a minor disease occurring on damaged fruit.
Chinese Cavendish, which retains trash around the
bunch, appears to be more susceptible than other
cultivars.
Symptoms
Extensive brown or dark water-soaked areas in the corm
cause breakdown of tissue. A dirty, white mould is
generally visible in cavities in the affected tissues.
Source of infection and spread
The fungus is a soil inhabitant that enters the corm mainly
through wounds.
Management
•
Follow the recommendations for managing leaf spot and
speckle to control black tip.
CERATOCYSTIS FRUIT ROT
■
Cause
The fungus
Ceratocystis paradoxa
.
Importance
Usually, Ceratocystis rot is a minor disease in corms used
for planting.
Management
•
Symptoms
An uneven black rot of hands of fruit extending from the
crown occurs. A white-to-grey fungal growth forms on
infected areas and a sweet smell is present. Once finger
stalks are infected, fingers readily drop from the hand.
Do not plant infected material.
CIGAR END
■
Cause
The fungus
Ve r t ic illium the obroma e
.
Source of infection and spread
The disease is a postharvest problem, and infection occurs
in cuts made to remove hands from the bunch. The main
sources of infection are old bunch stalks and discarded
fruit in and around the packing shed.
Symptoms
Cigar end is a firm, dark decay at the end of fruit
surrounding the dead f floral parts and extending back
along the fruit up to 20 mm. The infected area shrinks
and becomes more or less rounded in contrast to the
angular shape of immature fruit. The area later becomes
covered with an ashy grey coating of spores resembling a
burnt cigar tip. The fruit pulp undergoes a dry rot.
Generally, only a few fruit on the hand are affected.
Importance
Generally, Ceratocystis fruit rot is a minor disease but
serious outbreaks may occur in wet seasons.
Management
•
Remove banana refuse regularly from the packing shed.
Source of infection and spread
The fungus colonises banana f flowers and leaf trash and
infects fruit during wet weather.
CERATOCYSTIS CORM ROT
■
Cause
The fungus
Ceratocystis paradoxa
.
Importance
Cigar end is a minor disease during wet weather.
