Cocoa Mealybug

📖 Description

Cocoa Mealybug (Planococcus citri), also called Citrus Mealybug or Coffee Mealybug, is an important sap-sucking pest of cocoa across the Indian subcontinent, particularly severe in the major cocoa-growing belts of Kerala (Kozhikode, Malappuram, Palakkad, Thrissur), Karnataka (Dakshina Kannada, Udupi, Chikmagalur, Kodagu), Tamil Nadu (Nilgiris, Coimbatore, Dindigul), Andhra Pradesh (West Godavari, Krishna) and the Andaman & Nicobar Islands where India cultivates cocoa as an intercrop in coconut and arecanut plantations on over 80,000 hectares (India is one of the faster-growing cocoa producers in Asia, with cultivation expanding rapidly to meet domestic chocolate industry demand). The pest is unusual among cocoa pests because (a) it is highly polyphagous with over 200 known hosts including citrus, coffee, grapevine, banana, pineapple, sugarcane, cotton, mango and many ornamentals — allowing populations to persist between cocoa crops via weeds and intercrops, (b) the pest feeds preferentially on the pods and tender shoots where its damage is most economically damaging (sooty mold on pods reduces quality, deformed pods are unsaleable), (c) the pest is the known vector of Cocoa Swollen Shoot Virus (CSSV) — a devastating viral disease that has caused millions of tree losses in West Africa, and while CSSV has not yet been reported from India, the presence of the vector makes Indian cocoa highly vulnerable if the virus is introduced, (d) ant attendance is critical to the pest’s success — ants transport mealybugs to new feeding sites, protect them from natural enemies, and even build protective soil shelters over colonies, (e) a large part of the population lives in bark crevices, under pod stalks and in leaf axils making detection and control difficult — by the time foliar symptoms (yellowing, sooty mold) appear, the colony is well-established, and (f) the pest is most severe in poorly managed plantations with inadequate shade regulation (too much shade favours mealybug) and excessive use of broad-spectrum insecticides (which kill natural enemies). IPM with ant control, Cryptolaemus releases (the classical ‘mealybug destroyer’ ladybird), conservation of native parasitoids (Anagyrus, Leptomastix), Beauveria bassiana soil drenches for subterranean colonies, neem-based sprays, and need-based insecticide rotation provides effective and sustainable control. The pest is a particular concern for Indian cocoa growers because the rapid expansion of cocoa cultivation to meet domestic chocolate industry demand is largely happening through intercropping in existing coconut and arecanut plantations where mealybug populations are already established on the main crop — making early detection and quarantine of new cocoa plantings especially important.