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Diseases
Foot rot disease
Foot rot (quick wilt disease) caused by Phytophthora capsici is
the most destructive of all diseases and occurs mainly during the
south west monsoon season. All parts of the vine are vulnerable to
the disease and the expression of symptoms depend upon the site
or plant part infected and the extent of damage.
Symptoms
z One or more black spots appear on the leaves which have a
characteristic fine fibre like projections at the advancing margins
which rapidly enlarge and cause defoliation.
z The tender leaves and succulent shoot tips of freshly emerging
runner shoots trailing on the soil turn black when infected. The
disease spreads to the entire vine, from these infected runner
shoots and leaves, during intermittent showers due to rain splash.
z If the main stem at the ground level or the collar is damaged, the
entire vine wilts followed by shedding of leaves and spikes with
or without black spots. The branches break up at nodes and the
entire vine collapses within a month.
z If the damage is confined to the feeder roots, the expression of
symptoms is delayed till the cessation of rain and the vine starts
showing declining symptoms such as yellowing, wilting, defoliation
and drying up of a part of the vine. This may occur during October-
November onwards. These vines may recover after the rains and
survive for more than two seasons till the root infection culminates
in collar rot and death of the vine.
Management
The disease can be controlled by adopting integrated disease
management strategies.
Phytosanitation
z Removal and destruction of dead vines along with root system
from the garden is essential as this reduces the build up of
inoculum (fungal population).
z Planting material must be collected from disease free gardens
and the nursery preferably raised in fumigated or solarized soil.
Cultural practices
z Adequate drainage should be provided to reduce water
stagnation.
z Injury to the root system due to cultural practices such as digging
should be avoided.
z The freshly emerging runner shoots should not be allowed to
trail on the ground. They must either be tied back to the standard
or pruned off.
z The branches of support trees must be pruned at the onset of
monsoon to avoid build up of humidity and for better penetration
of sunlight. Reduced humidity and presence of sunlight reduces
the intensity of leaf infection.
Chemical control
Any of the following chemical control measures can be adopted.
z After the receipt of a few monsoon showers (May-June), all the
vines are to be drenched at a radius of 45-50 cm with copper
oxychloride 0.2 per cent @ 5-10 litres/vine. A foliar spray with
Bordeaux mixture one per cent is also to be given. Drenching
and spraying are to be repeated once again during August-
September. A third round of drenching may be given during
October if the monsoon is prolonged.
z After the receipt of a few monsoon showers, all the vines are to
be drenched with potassium phosphonate 0.3 per cent @ 5-10
litres/vine. A foliar spray with potassium phosphonate 0.3 per
cent is also to be given. A second drenching and spraying with
potassium phosphonate 0.3 per cent is to be repeated during
August-September. If the monsoon is prolonged, a third round of
drenching may be given during October. L
z After the receipt of a few monsoon showers, all the vines are to
be drenched with 0.125 per cent metalaxyl mancozeb @ 5-10
litres/vine. A foliar spray with metalaxyl mancozeb 0.125 per cent
may also be given.
z At the onset of monsoon (May-June), apply Trichoderma around
the base of the vine @ 50 grams/vine (this quantity is
recommended for a substrate containing Trichoderma @ 1010
cfu). A foliar spray with potassium phosphonate 0.3 per cent or
Bordeaux mixture one per cent is also to be given. A second
application of Trichoderma and foliar spray of Bordeaux mixture
one per cent or potassium phosphonate 0.3 per cent are to be
given during August-September.

Pollu disease (Anthracnose)
This disease is caused by Colletotrichum gloeosporioides. It can
be distinguished from the pollu (hollow berry) caused by the beetle
by the presence of characteristic cracks on the infected berries.
The disease appears towards the end of the monsoon. The affected
berries show brown sunken patches during early stages and their
further development is affected. In later stages, the discolouration
gradually increases and the berries show the characteristic cross
splitting. Finally, the berries turn black and dry. The fungus also
causes angular to irregular brownish lesions with a chlorotic halo
on the leaves. The disease can be controlled by spraying Bordeaux
mixture one per cent.
Spike shedding
Spike shedding especially in varieties like Panniyur-1 at higher
elevations like Kodagu and Idukki is one of the emerging diseases.
It is seen in serious condition when the pre-monsoon showers are
delayed and flowering and spiking occur during June-July.  These
spikes predominantly produce female flowers instead of bisexual
flowers. Heavy spike shedding may occur due to lack of pollination.
Irrigation of vines from second fortnight of March coupled with
prophylactic spraying with Bordeaux mixture one per cent or
carbendazim 0.2 per cent reduces the intensity of spike shedding.
Stunt disease
This disease which is caused by viruses is noticed in parts of
Kannur, Kasaragod, Kozhikode, Wayanad and Idukki Districts of
Kerala and Kodagu, Hassan and Uthara Kannada districts of
Karnataka. The vines exhibit shortening of internodes to varying
degrees. The leaves become small and narrow with varying degrees
of deformation and appear leathery, puckered and crinkled. Chlorotic
spots and streaks also appear on the leaves occasionally. The yield
of the affected vines decreases gradually.
Two viruses namely Cucumber mosaic virus and a Badnavirus
are associated with the disease. The major means of spread of the
virus is through the use of infected stem cuttings.  The disease can
also be transmitted through insects like aphids and mealy bugs.
The following strategies are recommended for the management of
the disease.

z Use virus free healthy planting material
z Regular inspection and removal of infected plants; the removed
plants may be burnt or buried deep in soil
z Insects such as aphids and mealy bugs on the plant or standards
should be controlled with insecticide spray such as dimethoate
or monocrotophos @ 0.05 per cent.
Phyllody disease
This disease which is caused by phytoplasma is noticed in parts
of Waynad and Kozhikode districts of Kerala. The affected vines
exhibit varying stages of malformation of spikes. Some of the floral
buds are transformed into narrow leaf like structures. Such
malformed spikes show leafy structures instead of floral buds,
exhibiting phyllody symptoms. In advanced stages, the leaves
become small and chlorotic, and the internodes are also shortened.
The affected fruiting laterals give a witches broom appearance.
Severely affected vines become unproductive. In severely affected
vines the entire spike is converted into small branches which appear
chlorotic and the vines decline rapidly. The infected vine becomes
unproductive within two to three years. The infected vines are to be
destroyed to prevent the further spread of the disease.
Slow decline (slow wilt)
Slow decline is a debilitating disease of black pepper. Foliar
yellowing, defoliation and die-back are the aerial symptoms of this
disease. The affected vines exhibit varying degrees of root
degeneration due to infestation by plant parasitic nematodes. The
diseased vines exhibit foliar yellowing from October onwards
coinciding with depletion of soil moisture. With the onset of south
west monsoon during May/June, some of the affected vines recover
and put forth fresh foliage. However, the symptoms reappear in
subsequent seasons after the cessation of the monsoon and the
diseased vines gradually lose their vigour and productivity. The
affected vines show varying degrees of feeder root loss and the
expression of symptoms on the aerial parts occur after a considerable
portion of the feeder roots are lost. The root system of diseased
vines show varying degrees of necrosis and presence of root galls
due to infestation by plant parasitic nematodes such as Radopholus
similis and Meloidogyne incognita leading to rotting of feeder roots.
The damage to feeder roots is caused by these nematodes and P.
capsici either independently or together in combination. There is
no spatial segregation of plant parasitic nematodes and P. capsici
in the soil under field conditions. Hence, it is necessary to adopt a
combination of fungicide and nematicide application for the
management of the disease.
z Severely affected vines which are beyond recovery should be
removed from the plantation and destroyed.
z The pits for planting should be treated with phorate 10 G @ 15
grams or carbofuran 3 G @ 50 grams at the time of planting.
z Nematode free rooted cuttings raised in fumigated or solarized
nursery mixture should be used for planting in the field.
z Phorate 10 G @ 30 grams or carbofuran 3 G @ 100 g/vine should
be applied during May/June (with the onset of south west
monsoon) and September/October. Along with nematicides the
basins should be drenched with either copper oxychloride 0.2
per cent or potassium phosphonate 0.3 per cent or metalaxyl
0.125 per cent.
In areas severely infested with root knot nematodes, cuttings of
the resistant variety ëPournamií may be planted.  Biocontrol agents
like Pochonia chlamydosporia or Trichoderma harzianum  can be
applied @ 50grams/vine twice a year (during April-May and
September-October). The fungus load in the substrate should be
108
 cfu/g.
While applying nematicides, the soil should be raked in the basin
of the vine lightly without causing damage to the root system and
the nematicide should be spread uniformly in the basin and covered
with soil immediately. Sufficient soil moisture should be ensured at
the time of nematicide application. The control measures should be
taken up during early stages of the disease.
Insect pests
Pollu beetle
The pollu beetle (Longitarsus nigripennis) is the most destructive
pest of black pepper and is more serious in plains and at altitudes
below 300 meters. The adult is a small black beetle measuring about
2.5 mm x 1.5 mm, the head and thorax being yellowish brown and
the fore wings (elytra) black. Fully-grown grubs are creamy-white
and measure about five mm in length.
The adult beetles feed and damage tender leaves and spikes.
The females lay eggs on tender spikes and berries. The grubs bore
into and feed on the internal tissues and the infested spikes turn
black and decay. The infested berries also turn black and crumble
when pressed. The term pollu denotes the hollow nature of the
infested berries in Malayalam. The pest infestation is more serious
in shaded areas in the plantation. The pest population is higher
during September-October in the field.
Regulation of shade in the plantation reduces the population of
the pest in the field. Spraying quinalphos (0.05 per cent) during
June-July and September-October or quinalphos (0.05 per cent)
during July and Neemgold (0.6 per cent) (neem-based insecticide)
during August, September and October is effective for the
management of the pest. The underside of leaves (where adults
are generally seen) and spikes are to be sprayed thoroughly.
Top shoot borer
The top shoot borer (Cydia hemidoxa) is a serious pest in younger
plantations in all black pepper areas. The adult is a tiny moth with a
wing span of 10-15 mm with crimson and yellow fore wings and grey
hind wings. The larvae bore into tender terminal shoots and feed
on internal tissues resulting in blackening and decaying of affected
shoots. Fully-grown larvae are grayish green and measure 12-15
mm in length. When successive new shoots are attacked, the growth
of the vine is affected. The pest infestation is higher during July to
October when numerous succulent shoots are available in the vines.
Spray quinalphos (0.05 per cent) on tender terminal shoots; repeat
spraying at monthly intervals (during July-October) to protect
emerging new shoots.
Leaf gall thrips
Infestation by leaf gall thrips (Liothrips karnyi) is more serious at
higher altitudes especially in younger vines and also in nurseries in
the plains. The adults are black and measure 2.5-3.0 mm in length.
The larvae and pupae are creamy white. The feeding activity of
thrips on leaves causes the leaf margins to curl downwards and
inwards resulting in the formation of marginal leaf galls. Later the
infested leaves become crinkled and malformed. In severe cases of
infestation, the growth of younger vines and cuttings in the nursery
is affected. Spray dimethoate (0.05 per cent) during emergence of
new flushes in young vines in the field and cuttings in the nursery.
Scale insects
Among the various scale insects recorded on black pepper,
mussel scale (Lepidosaphes piperis) and coconut scale (Aspidiotus
destructor) cause serious damage to black pepper vines at higher
altitudes and also to older cuttings in nurseries in the plains. Females
of mussel scales are elongated (about one mm length) and  dark
brown and that of coconut scales circular (about one mm in diameter)
and yellowish brown. Scale insects are sedentary, remaining
permanently fixed to plant parts and appear as encrustations on
stems, leaves and berries. They feed on plant sap and cause
yellowing and wilting of infested portions; in severe cases of
infestation the affected portions of vines dry up. The pest infestation
is more severe during the post monsoon and summer periods.
Clip off and destroy severely infested branches. Spray dimethoate
(0.1 per cent) on affected vines; repeat spraying after 21 days to
control the infestation completely. Initiate control measures during
early stages of pest infestation.  In nurseries spraying neem oil 0.3
per cent or Neemgold 0.3 per cent or fish oil rosin three per cent is
also effective in controlling the pest infestation.
Minor pests
Leaf feeding caterpillars, especially Synegia sp., damage leaves
and spikes of younger vines and can be controlled by spraying
quinalphos (0.05 per cent). Mealybugs, gall midges and aphids infest
tender shoots especially in nurseries. Spraying of dimethoate (0.05
per cent) may be undertaken if infestations are severe. Mealybug
infestation on roots can be controlled by drenching with
chlorphyriphos (0.075 per cent) and undertaking control measures
against Phytophthora and nematode infections.

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