Controlling cocoa mealy bug

Controlling cocoa mealy bug
Pest attack is more in July-October
Cocoa is now becoming popular as a mixed crop in coconut plantations.
The cocoa mealy bug, Planococcus lilacinus is the most important insect attacking cocoa trees.
The nymphs and adults of mealy bug occur in colonies and infest growing shoots, terminal buds, flower stalks, foliage and pods and start sucking the sap.
Growth of followers is suppressed, young pods dry up, tender leaves are deformed into hair like structures.
Sunken patches in the developing pods result in the formation of scabs. Brown patches, irregular cracks and pits can be seen on mature pods.
The adults excrete honey dew on the leaves over which a sooty mould develops which in turn inhibits photosynthetic activities of the plant.Life history
Mealy bugs are small, oval and light yellow. Nymphs are usually disseminated by wind. A female can lay around 200 eggs which hatch into nymphs within six hours. Nymphal period lasts for 20-25 days.
Their incidence is maximum during July-October. Ants are attracted to the sugary substance excreted by the mealy bugs and thus ants serve as protective and carrying agents for them.Control methods
Neem oil suspension of 3 per cent may be sprayed on pods and foliage at the early state of nfestation.
Spray 0.05 per cent fenthion, dimethoate or phosalone.
Spot application of insecticide is to be undertaken when the population reaches above 15 per cent in the field.
The insecticide must be applied only after collecting the pods which are ready for harvesting.
Give a second round of spray after 30 days if the incidence persists.
Soil drenching of monocrotophos or dimethoate is also found to be effective.
Larvae of certain blue butterflies and coccinellid beetles are predaceous on the mealy bug in nature.
Release predatory lady bird beetles at 5-10 adults/tree.
Destroy ant nests to minimise the spread of the pest.
J. JAYARAJ & M. ANANTHAN
Horticultural Research Station, Thadiyankudisai Perumparai Dindigul, Tamil Nadu