 PLANT
PROTECTION
A.
Pests
The
major insect pests of the coconut palm are the
rhinoceros beetle, the red palm weevil, the black
headed caterpillar, the cockchafer beetle and
the coreid bug. Adopt suitable remedial measures
as and when required. The following table gives
the major symptoms and control measures.
I.
Rhinoceros Beetle
Symptoms
The adult beetle bores into the
unopened fronds and spathes.
Attacked fronds when fully opened
show characteristic geometric cuts
Control measures
Hook out the beetle from the attacked
palms using beetle hook.
As a prophylactic measure, fill up the top most
three leaf axils with Sevidol 8G(25g) + fine sand
(200g) thrice in April, September and December.
OR
Place 10.5g naphthalene balls
in the leaf axils and cover it with fine sand.
To be practiced once in 45 days.
Spraying 0.01% Carbaryl (50WP) in the breeding
sites of the beetle help destroy the larva.
Biological control using the virus Baculovirus
oryctus (release 10 - 15 virus infected beetles
in 1 ha)
AND
green muscardine fungus, Metarrizhium
anisopliae (spray 250ml Metarrizhium culture +
750ml water in manure pits and other breeding
sites of the beetle)
Practice clean cultivation.
Video Film on Integrated management of Rhinoceros Beetle
II.
Red Palm Weevil
 Symptoms
Presence of holes on the stem,
oozing out of viscous brown fluid and extrusion
of chewed up fibres through the hole.
Some times the gnawing sound
produced by the feeding grubs will be audible.
In the advanced stage of infestation
yellowing of the inner whorl of leaves occur.
The crown falls down or dry up
later when palm is dead.
 Control measures
Practice clean cultivation by
cutting and removing palms already damaged and
the decaying stumps in the garden. Such palms
should be split open and the different stages
of pest inside burned off.
Avoid injury to the trunk as
the pest lay eggs in these wounds. Wounds if
any, should be pasted with a mixture of carbaryl
/ Thiodan and soil. While cutting leaves, retain
at least 1m of petiole.
Use pheromone trap for attracting
weevils and kill the collected ones.
If rhinoceros beetle attack is prevalent, follow
the recommended measures.
Use fungicides if leafrot / bud rot is noticed
as the weevil lays eggs in such palms.
Inject attacked palms with 0.1% Endosulfan (3ml
/ litre water) or 1% Carbaryl (20gm/litre).
Plug the holes in damaged region and pour the
insecticide suspension into a slanting hole
made above the damaged portion using a funnel.
Then plug this hole also. If needed repeat after
one week.
III.
Black headed Caterpillar
 Symptoms
Severity of attack is seen during
January to May. The caterpillar feeds on
green matter from lower leaf surface, remaining
within silk and frass gallaries. In severe
attack all the green matter of the leaves will
be eaten up.
Control measures
Bioligical control is very effective
against this pest through release of parasitoids
like Gorriozus nephantidis, Elasmus nephantidis
and Brachimeria nosatoi.
In case of severe attack, remove the affected
leaves and destroy by burning. Then spray the
under surface of leaves with 0.02% Dichlorvos
(Dichlorvos 100EC).
IV.
Coreid Bug
Symptoms
The attacked buttons do not develop
resulting in immature nut fall. The nuts if developed
may become barren.
Control Measures
Pesticide application is necessary
if infection is severe. Spraying has to be done
3 times a year.
Apply 0.1% Carbaryl or Endosulfan on the inflorescence
after the receptive phase of the female flowers.
Destruction of pollinating insects can be avoided
if spraying is done in afternoon hours.
Tying perforated polybags (2 bags/palm) containing
2.5g phorate on to the stalk of inflorescence
is also effective.
V.
Rats
Symptoms
Attack tender nuts resulting in
immature nut fall.
Control measures
Entry of rats on to the trunk
can be prevented by fixing mechanical barriers
upto 2m height from ground level using 40cm sized
G.I. sheets.
Use rat traps.
Poison baiting with zinc phosphide or warfarin.
Fumigate the hiding places using Aluminium phosphide
tablets.
Place wax blocks containing the poison Bromodioline
@ 30 blocks per ha (each weighing 10g) on 5 palms.
Repeat after 12 days. Practice this two times
for reducing rat population.
VI.
Lace Bug
Symptoms
Lace
bug sucks sap from coconut foliage; it acts as
a vector in transmission of Phytoplasma from root(wilt)
affected palms to healthy palm.
Control
measures
This
can be controlled by spraying Endosulphan or Monocrotophos
0.01%.
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