Managing fruit fly in mango

The mango fruit fly is believed to be the single largest crop damager in India. It accounts for about 27 per cent of harvesting loss. The flies attack semi ripe and mature fruits during the months of April and May. Other fruits like guava, citrus, plum, peach, sapota, loquot, etc are also susceptible to this pest attack.

Damage is caused both by adults and maggots. Adult female punctures the rind of near ripe fruits with its needle like ovipositor and lays eggs.

Maggots

The legless yellowish maggots after hatching bore and feed on fruit pulp and on maturity come out of the fruit, drop on the ground and pupate deep under the soil. Thus the maggots destroy the pulp making it foul smelling and discoloured. Infested fruits develop brown rotten patches on them and fall to the ground ultimately.

Management

— Collect the fallen infested fruits and dispose them by dumping and burying in 60 cm deep pits.

— Plough the interspaces in the orchard during summer to expose fly puparia to kill them under hot sun rays.

— Timely harvest of mature fruits should be done and the fruits may be treated with hot water for one hour at 48 degree celcius.

— Install methyl eugenol traps at 6 nos./acre

— Adopt male annihilation technique of using bait traps with 100 ml of 0.1per cent methyl eugenol (1ml/lit) and 0.05 per cent malathion 50EC (1ml/lit) taken in 250 ml capacity wide mouthed bottles fitted with hanging devices.

— Another poison bait may be prepared by adding 100g of jaggery and 2ml of decamethrin 2.8EC in 1 lit of water and sprayed on the tree trunks at weekly interval. The bait could be sprayed on the nearby hedges and vegetation.

— Spray deltamethrin 0.025 per cent thrice at least 15 days interval commencing 45 days after fruit set.

— Spraying of 0.03 per cent dimethoate up to two weeks period to picking the fruits is also effective.

(Dr. J. Jayaraj, Professor and Dr. M. Kalyanasundaram, Professor and Head, Department of Entomology

Agricultural College and Research Institute, Madurai 625 104, Phone No. 0452-2422956, extn.214, email: agentomac@tnau.ac.in)