Mango Injurious Insects

A Lecture To ToT trainees ( FFS)

By Mr. Allah Dad Khan

Provincial Coordinator IPM KPK

MINFAL Pakistan

Bark Eating Caterpillar

  The caterpillar ( Indarbella quadrinotata ) is found to infest

a variety of plants including fruit trees and ornamentals in India . Dense, old and neglected orchards are more prone to attack of this pest. Larvae of this pest feed on the tree bark and spin brown silken web which consist of its excreta and wood pieces and make tunnels in the stem and branches. Larvae generally feed from April to December and have only one generation in a year. The population of this pest can be reduced by keeping the orchard clean and removal of webs from tree trunks and filling the insect holes with emulsion of Monocrotophos (0.05%) or DVVP (0.05%) and plugging with mud.

Fruit piercing moth

Dmage :Major and sporadic. Several genera of noctuid moths are fruit piercing but the most damaging are Eudocima fullonia, E. materna, E. jordani and E. salaminia.

Moths feed at night by penetrating the skin of the ripe or ripening fruit with their strong proboscis and sucking the juice. Internal injury consists of a bruised, dry area beneath the skin. Secondary rots develop at the puncture site. Secondary-moth feeders often visit fermenting fruit, taking advantage of the access holes the fruitpiercing moths drill. Early summer to early autumn is the most important period.

Mango moth

Eudocima salaminia moth resting on a fruit.

Eudocima fullonia with wings pinned out.

Mango seed weevil

DamageThe mango seed weevil is considered a minor pest as it causes no significant economic damage to fruit. The minute egg-laying scars are barely discernable at harvest and the weevil is present only within the seed. The fine tunnel in the flesh the young larva causes as it burrows towards the seed heals, leaving no sign of its earlier presence in the flesh. However there are quarantine restrictions on the movement of mango fruit infested with seed weevil into a number of markets.

Mango Weevil

Adult mango seed weevil on a mango leaf.

Egg on mango fruit

Mango Stem borer

Stem Borer Stem borer ( Bactocera rufomaculata ) is widely distributed in

India and attack a number of fruit trees including mango. The grub of this pest feeds inside the stem, making tunnel upward which results in drying of branches and in severe cases death of tree. Eggs are laid either in the cracks of tree trunk or in the cavities of main branches which covered with viscous fluid. Grub pupates inside the stem and beetle emerges in July/August. There is only one generation of this pest in a year. The pest can be kept under check by maintaining the orchard clean and applying propanophos (0.05%) or Imidaclopid (0.005%) or DDVP (0.05%) in hole of insect and plugging with mud

Mango Shoot Caterpillar

Mango shoot caterpillar (Penicillaria jocosatrix).

Mango leafhopper

Three species of hoppers Idioscoynio chypeabis, I. nitidulus and Amritodus atkintoni are the most important and found on panicles, leaves and stems, respectively. The adult and nymphs of hoppers, suck the sap from tender parts resulting in reduction of vigoure. Heavy infestation causes curling and drying of infested parts. Inflorescence infestation results in complete loss of crop. The hoppers after sucking, excretes sweet sticky substance which facilitate the development of fungi, Maliola and Capnodium spp., commonly known as sooty mould which gives black look to the trees and affects photosynthetic activity. Hoppers are present round the year in the orchard but population used to be high during February to April and June to August. The hoppers can be managed by pruning of dense orchards in the month of December, orchard sanitation and 3 sprays of Carbaryl (0.02%) or Propanophos (0.05%) or Imidachlopid (0.005%) at early stage of panicle formation if, population exceeds from 10 hoppers per panicle. The second spray should be given at full length of panicle but prior to full bloom and third at pea stage of fruits. Nymph predators Mallada boninensis and Chrysopa lacciperdaand egg parasite Polynema sp., Gonatocerus sp. and Tetrastichus sp. are found effective in nature against the hoppers. A fungus, Verticillium lacani has also been found effective against this pest but under moderate climate. Spraying of Nimbicidine (0.2 %) is effective at initial stage of hoppers management.

Figure 1: Mango leafhopper adult (top) and nymph

Figure 2: Black sooty mould and flower damage

Leaf Hopper

Mango stem miner

Damage:Where it attacks healthy trees in commercial growing situations, mango stem miner does not appear to adversely affect flowering and fruiting. Limited information from Thailand indicates that it does not significantly affect production.

Leaf miner

Figure 1: Mango stem miner larvae

Figure 2: Mango stem miner damage

Mango fruit fly

The oriental fruit-fly is one of the most important pests of mango and considered to be a major hurdle in export of fresh fruits. The three species of fruit-fly, i.e., Bactrocera dorsalis , B . zonatus and B. correctus are the most common and causes severe damage to mature mango fruits. The female insert eggs in small clusters inside the mesocarp of the mature fruits and after hatching larvae feeds on the pulp which appears normal from outside but finally drops down. The maggots pupate in soil and flies start emerging from April onwards with maximum population during May to July which coincides with fruit maturity. Collection and destruction of infested and dropped fruits ploughing of orchards, use of trap bottle containing 100ml watery emulsion of methyl euginol (0.1%) + Malathion (0.1%) during April-June) reduce the infestation of this pest. Wooden traps prepared with sex hormone and insecticide has also been found effective against the pest. Bait spray of Carbaryl (0.15%) + protein hydrolysate (0.1%) or molasses at 21 day intervals starting from first week of April found effective in control of adult flies. Early harvesting of mature fruits, selective and need based bait spray and hot water treatment of harvested fruits before storage showed promising result.

Fruit Fly

Adult Queensland fruit fly (Bactrocera tryoni).

Larvae of Queensland fruit fly with damaged (darker) areas of fruit. Note the black mouth parts in the head of each larva.

Red banded mango caterpillar

An obvious external sign of infestation is the presence of a liquid exudate from the mouth of a tunnel chewed by the caterpillar through the skin. It trickles down to the tip of the fruit and accumulates. Although almost clear when fresh, the liquid darkens and shows up as a dark streak on the skin leading to a dark spot at the fruit tip.

Early signs of infestation may not be as easily seen and could include small darkened boreholes on the fruit caused by entering larvae.

Damaged fruit may be attacked secondarily by fruit flies or various decaying organisms and may fall from the tree prematurely

Red Banded Mango Caterpillars

The red banded mango caterpillar larvae are plump, glossy and brightly banded with a black collar near the head. The larvae tunnel into the fruit, depositing caterpillar frass at the tunnel entrance

Once inside the fruit, the larvae eat the seed and cause the fruit to rot and fall off the tree

Mango thrips

DamageMajor and sporadic.

Both immature and adult thrips suck sap from cells. The preferred feeding site for thrips is the tissue next to the midrib on the undersurface of leaves, but in severe infestations fruit is also attacked. The first sign of damaging is a silvering of leaves and fruit.

In severe infestations, the silvering develops a pale yellow to brown discolouration, speckled darkly with dried droppings. This insect causes damage to mammey, cashew and mangosteen.

Thrips

Young mangosteen fruit damaged (brown discolouration) by red-banded thrips

Juvenile red-banded thrips (Selenothrips rubrocinctus) hiding underneath a mangosteen fruit calayx

Mango whitefly

Whiteflies feed on the undersides of foliage. Heavily infested plants with very high whitefly populations soon develop a black sooty appearance from mould growing on the sugary secretions that the whiteflies and their nymphs produce. This sooty mould, in combination with leaf damage, reduces the plant's ability to photosynthesise. It also weakens, or in some cases kills the plant. When its natural biological agents are not present, spiralling whiteflies multiply at a rapid rate, producing thousands of individuals on a single plant.

Figure 1: Spiralling whitefly - spirals, nymphs and adults on banana leaf

Figure 2: Heavy infestation on banana leaf

Mango Mealy bugs

It is another major pest of mango in India and widely distributed along the Indo-gangatic plain. The most common mealy bug is Drasicha mangiferae , which causes severe damage to mango crop through out the country. Adults and nymphs both sucks the plant sap and reduce the plant growth, destroy inflorescence and causes fruit drop. Mealy bug excretes honey dew, a sticky substance, which facilitates the development of sooty mould fungi ( Maliola mangiferae & Capnodium mangiferae ). The female insect crawls down in the month of April/May to lay the eggs in soil. The eggs hatch in the following month of November/December and crawls up the tree. Flooding the orchard in the month of October and deep ploughing in November, fastening of alkathene 25 cm wide sheet (400 gauge) afterwards mud plastering of trunk at 30 cm above the ground in the middle of December, loosening of soil around the tree trunk and mixing of Chlorpyriphos dust (1.5%) @ 250 g per tree helps in reduction of mealy bug population. This dust can also be applied below the alkathene band on tree trunk and soil. Spraying of Propanophos (0.05%) or Imidachlopid (0.005%) for control of nymphs already made the way up to tree. The integrated approach (IPM) of above has been found effective in management of mealy bug but spraying of neem products along with soil application of Beauveria bassiana spores will be further useful in population reduction of this pest. Apart from B. bassiana , coccinellid beetles (predator), Minochillus sexmaculatus , Rodolia fumida andSuminus renardi are natural bio-control agents of this pest.

Inflorescence Midge

In recent years, the inflorescence midge ( Erosomyia indica ) became serious in certain mango growing pockets particularly in Uttar Pradesh, affecting both inflorescence and small fruits. It affects the crop at 3 stages, i.e., at floral bud burst, fruit set and tender leaves particularly encircling the inflorescence. The first phase is more damaging as the entire inflorescence destroyed before flowering and fruit set. The inflorescence show stunting growth and its axis has curve at the entry point of the larvae and ultimately die before fruit set. Its attack on inflorescence could be recognized by presence of tiny black spots. Apart from inflorescence midge, 2 other gall midges, Dasineura amramanjarae and Procystiphora mangiferae have also been found infesting mango inflorescence. The larvae of D. amramanjarae are red, while P. mangiferae are orange in colour. Accordingly D. amramanjarae infected parts are red whereas P. mangiferae are swollen and bigger (bud) in comparison to normal. The pest can be managed by ploughing of orchards and spraying of Propanophos (0.05%) or Imidachlopid (0.005%) at bud burst stage of inflorescence.

Leaf Webber

  The leaf webber ( Orthaga euadrusalis ) infestation starts

from the month of April and continues up to December. Eggs are laid singly or in clusters in the webs on leaves. After hatching, the caterpillar feeds on leaf surface and make web of tender shoots and leaves together and feeds inside. Pupation also takes place inside the web but last generation (December-January) pupates in soil. Pruning and destruction of infested shoots during April to May, ploughing of orchards and loosening of soil around the trees in January and spraying (2-3) with Carbaryl (0.2%) or Propanophos (0.05%) or Imidaclopid (0.005%) at 15-days interval reduces the population of this pest.

Shoot Gall Psylla

The shoot gall psylla ( Apsylla cistallata ) is very serious on mango in Tarai region of India , North Bihar and West Bengal . Infestation of this pest results in formation of green conical galls in leaf axis. The pest becomes active from the month if August and galls dry after emergence of adults in the month of March. The eggs are laid in the midrib as well as on lateral axis of new leaves in March/April, nymphs emerges during August/September and feeds on adjacent buds which later turn in to hard green conical gall. Galls are more prominent during September/October and infested plants usually devoid of flowers and fruits. There is only one generation of this pest in a year The pest can be managed by avoidance of new planting in humid region, removal and destruction of infested plant parts and use of Monocrotophos (0.05%) or Imidachlopid (0.005%) or Propanophos (0.05%) at fortnightly intervals.

Scale Insects

In recent years, scale insects ( Chloropulvinaria polygonata, Aspidiotus destructor and Rastococcus sp) became serious on mango. The nymphs and adults of pest suck the sap of leaves and other tender parts which results in reduction of vigour of plants. Scale also secrets honeydew which facilitates in development of sooty mould on different plant parts. Among these scales, C . polygonata is posing threat to mango industry particularly in Western Uttar Pradesh. Pruning and destruction of infested plant parts and spraying with Monocrotophos (0.05) or Imidachlopid (0.005) or Propanophos (0.05%) at an interval of 21-days found effective in population reduction of this pest.

Insect pests of mango, viz. mealy bug, hopper, midge, fruit fly could be managed through IPM schedule involving banding of tree trunk with alkathene (400 gauge) and drenching with Beauveria bassiana (2 g/l) during first week of January and first spray with Neem Seed Kernel Extract (5%) in first week of February followed by second spray of imidadoprid (0.005%) when panicles are of 5 to 7 cm size and third need based spray with Propanophos (0.05%) after fruit set.