A short guide on common Cacao pest and disease management, published by the Philippine Agricultural Training Institute. Cacao growers can benefit from additional information provided to keep their farms a viable agribusiness venture.

1. Information, education and
communication materials series no. 9-5

2. • In heavily infected plantations, remove very
susceptible trees to provide wider space
between trees, reduce shade and prune
regularly.
5. Ceratocystis wilt (Ceratocystis fimbriata)
• The fungus enters through wounds especially
those damages caused by wood-boring
beetles and pruning knives.
• Stress predisposes the trees to beetle and
fungal infection.
Symptoms
Prevention and Control Measures
• Minimize damage at pruning and harvesting.
• Sterilize the cutters after completion of work
on each tree by incorporating fungicide in the
scabbard or by painting fungicide on all large
exposed surfaces.
Writer
MA. NORMA G. MADDALORA
Information Officer II, ATI-RTC 02
Technical Editor/Subject Matter Specialist
ENGR. WILLIAM V. CONTILLO
HVCC Coordinator
DA-CVIARC, Ilagan, Isabela
Graphic Artist
DANICA E. MELEGRITO
Editor
ANTONIETA J. ARCEO
Head, ISD, ATI
Advisers
RENATO MAGUIGAD
Center Director, ATI-RTC 02
ASTERIO P. SALIOT, PhD, MNSA, CESO III
Director, ATI 13

3. L
ike any other crop, many destructive pests
and diseases limit the production of cacao.
A farmer’s major concern is to keep his farm
a viable business venture. To do so, one of the
most important thing he has to do is to keep the
level of pests and diseases below the economic
threshold level.
Common pests and diseases of cacao and the
management practices to control are here to
guide cacao growers on how to prevent and
control insect pest and diseases.
INTRODUCTION
• In heavily infected plantations, remove very
susceptible trees to provide wider space
between trees, reduce shade and prune
regularly.
4. ROOT ROT DISEASE (Rigidoporus lignosus - white
root rot, most common; Pliellinus noxious- brown
root rot; and Armellaria mellea - collar crack, fungi)
Symptoms
• Leaves are dull and lacks luster.
• Branches cease producing new flushes. After
few weeks, leaves simultaneously turn yellow
and brown. Wilted leaves remain attached to
the trees for some time.
• For white root rot, roots and trunk base turn
brown on which white, thread-like rhizomorphs
may be seen.
• For brown root rot, there is hard, brittle
encrustation of soil around the root and
base of trunk, held by exudates from brown
rhizomorphs.
• For collar crack, a one to two meter crack in
the base of the stem causes the tree to fall.
Prevention and Control Measures
• Plant resistant cultivars.
• Treat the canker by scraping off the outer bark
and painting a fungicide onto the canker.
• Cut and burn big infested trees.
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4. 1. MIRIDS OR CAPSIDS (Helopeltis baker
Pappius and H. collah Stal.)
Damage Characteristics
• Sucks the juice of the plants.
• Damage results in the formation of small
water-soaked area of tissue which rapidly turns
black.
• On pods, lesions are circular but on stems, they
are oval and bigger.
• Direct feeding results in wilting and terminal
death.
• Cultural conditions in the field influence the
pattern of atttack. If there is no overhead
shade, the damage is widespread and the
general scorched appearance that results
from the many damaged shoots is known as
“capsid blast.” If there is overhead shade,
damage is localized below the gaps in the
shade cover.
Control Measures
• Plant seedlings of a vigorous variety.
• Cover gaps in the canopy of cocoa using
banana which should be removed as the
canopy closes.
• Cover gaps in the overhead shade.
INSECT PESTS • Weeding of badly affected areas.
• Annual foliar spray of the mineral, boron, can
increase pod set and reduce cherelle wilt
thereby making the trees less susceptible to
borer attack.
• Apply fungicides if cultural control measures
fails.
3. STEM CANKER (Phytophthora sp.)
Symptoms
• Early detection is difficult because infected
bark does not show external symptoms.
• In resistant cocoa varieties, host scar tissues
form around the lession and secondary fungi
take over. The infected tissue turns brown
and is invaded by insects which remove the
diseased tissue to leave a clean scar.
• In susceptible varieties, the active phase of
Phytophthora is more prolonged and the
secondary fungi do not take over. The canker
remains for several months, sometimes years. It
serves as inoculum for infection of other plant
organs. There is also a bright red exudate from
the canker.
Prevention and Control Measures
• Plant resistant cultivars.
• Treat the canker by scraping off the outer bark
and painting a fungicide onto the canker.
• Cut and burn big infested trees.
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5. 2. CACAOPODBORER(ConopomorphaAcrocercops)
• Most serious pest of
cacao in the Philippines.
• Larvae bores through
the husk and make long
frass-filled galleries in the
pulp.
• Callus form inside pod
that affects bean
development resulting
in a hard gall-like mass
inside the pod.
• Pods in the canopy
are more infested than
those in the trunk.
• Strip pods (rampasan) of more than 5cm length
from farm or plantation once or twice a year
at periods of low fruiting, to break the breeding
sequence of the moth.
• All pods removed should be buried.
• Cover developing pods with transparent plastic
sleeves open at the bottom (sleeving).
• Bagging can also be done. Harvest a little early
and place the pods in large polyethylene bags to
prevent the successful emergence and pupation
of larvae.
• Husks and waste after pod breaking should either
be buried or tied up in polythene sacks until well
decayed.
• Plant infested area with coffee or Hevea to make
a natural barrier against spread of the borer.
• Before pruning, the trees should be given all
the necessary conditions for growth such as
fertilizer, control of foliage pests, and suitable
shade.
• Movement of infected pods should be
restricted.
2. CACAO POD ROT (Phytopthora palmivora)
Symptoms
• Small brown spots appear on the pods at early
stage of infection, In one to two weeks, spots
cover the whole pod.
• Beans from immature pods are totally
destroyed. In mature pods, there is gap
between the beans and the husk.
Prevention and Control Measures
• Prune non-productive branches and remove
weeds regularly.
• Gradual removing of shade and adequate
maintenance of drainage canals will lessen
disease incidence.
• Practice frequent harvesting of mature pods
and removal of diseased pods.
• Modify the soil environment by applying lime to
increase soil pH and suppress Phytopthora.
Symptoms
Prevention and Control Measures
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6. • Frequent harvesting of ripening pods and
splitting as soon as the pods are harvested.
• Remove all alternate plants out of the cacao
plantation.
• Use pod husks for mulching.
• Put all harvested pods in a heap over a plastic
sheet and place dried cocoa leaves on the
heap for the borer to pupate. Collect the
pupae on the leaves after three days and
destroy.
• Use synthetic sex pheromones to attract and
trap male pod borers.
• Release of Trichogrammatoidea sp. at the rate
of 30 million individuals in 12 months resulted in
decreased pod damage.
Damage Characteristics
• Damage follow severe water stress, fungal
damage of stem and roots, mechanical
damage and extreme senesence.
• Damage are small round entrance holes in
the trunk or branches of trees and in stems of
seedlings.
• These beetles are also called coffee stem
borers. They attack in the shaded areas and in
weedy grounds.
DISEASES OF CACAO
1. VASCULAR STREAK DIEBACK
(Caused by Oncobasidium theobromae fungus)
This is a common disease affecting both adult
cacao trees and seedlings. The spores are wind-
borne and are produced at night after rainfall. The
fungus enters the xylem of young leaves and moves
towards the branches and the trunk. From initial
infection, it usually takes three to five months for
symptoms to appear.
Symptoms
• Leaves of shoots of seedlings dry up.
• In trees, leaf of the second or third flush behind
the branch tip turn yellow. Distinctive round, green
spots appear.
• An affected branch still have the youngest and
oldest leaves but no middle leaves.
• When infected branches are split longitudinally,
brown streaks of wood tissues appear inside the
branch.
• Infected matured trees may not die but its yield is
severely affected. Infected seedlings often die.
3. AMBROSIA BEETLE (Xylosandrus compactus)
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7. Control Measure
Clear the area around the trees and plant barrier
crop between cocoa and bush or coffee areas
provided that the second crop is not coffee.
4. MEALY BUG (Planococcus lilacintis Cockerell)
Damage Characteristics
• Feeds on leaves, young shoots, flower cushions
and developing fruits.
• Feeding causes distorted shoots, stunted
growth and wilted cherelles.
Control Measure
• Spray with synthetic or organiphosphate
insecticides when severe.
5. CURCULIONID BEETLE (Pizilicoptus iligantis)
Damage Characteristics:
• Damage is manifested as skeletonized leaves
and black scars on the fruits.
• Stack the beans away from the wall
• Regular inspection of the bags and rotation
of the stock is necessary.
• During off season, the warehouse should
be cleaned regularly.
11. COFFEE BEAN WEEVIL(Aracceras fascictilatus)
Control Measure
Damage Characteristics
The insect pierce the shell of the beans hence,
providing entrance to the tropical warehouse
moth and for molds.
Control Measures
• Fumigate the stocks using methyl bromide or
phosphine. The stacks of cocoa should be
sheeted and sealed during fumigation.
• After fumigation, the stacks of cocoa and the
warehouse should be properly ventilated to
ensure that the gas is removed.
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8. Control Measure
• The first two years of cacao establishment is
very important in the control of this pest. After
that, the plants can tolerate the feeding of the
beetle.
• Spray synthetic pyrethroids, carbamates and
cyhalothrin if infestation is severe.
6. CHAFER BEETLE (Anomala sp. and Adoretus sp.)
Damage Characteristics
• Major pest during the early establishment of
cacao plantation.
• Feeds exclusively on leaves.
• Adults attack throughout the young stages of
cacao.
• Feeding retards growth or completely defoliates
trees.
7. TUSSOK MOTH (Orgijia australis postica Walker)
Damage Characteristics
• Larva feeds on the leaves.
• High larval infestation defoliates the trees.
• They also attack cherelles or young developing
pods.
Control Measure
Spray synthetic pyrethroids, fenitrothion and
carbamates if infestation is severe.
8. STEM BORER (Zeuzera coffeae Nietner)
Damage Characteristics
• Eggs are layed in cluster in cracks of bark.
• Larvae burrow in the bark.
• Pupae form in the larval burrow.
9. TROPICAL WAREHOUSE MOTH (Epliesna cautella)
• It finds broken, cut or germinated beans for
survival as it cannot penetrate properly dried
cocoa beans.
• It feeds on the moist of germinating beans.
Damage Characteristics
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