v Mango leaf hopper: (Idioscopus clypealis)
Hemiptera : Cicadellidae
v Geographical distribution:
Distributed in India, Malaysia, Indonesia and Formosa. No alternative host plants of these insects
are known.
v General body characters:
There are three dark brown spots on the head, a median band and the two
black spots on the pronotum The nymphs of this pest is dust yellow. Adults of
the large mango hopper measures 6.3mm length and are grayish.
v Life cycle:
The pest is particularly active throughout the year but during hot months of may- June and the cold months of October-July only adults are found sitting thousand on the
bark of trunks, branches etc. a female deposits on an average of 200 eggs , a moderate
temperature being more conductive to egg laying. Within 4-7 days the eggs hatched
and the newly emerge larvae are first seen at the end of February or in the
early march. The nymphs then migrate to the stem and the young leaves, and full
grown in three stages in 8-13 days. The life cycle from the time eggs are laid
to the time the adult hopper takes 15-19 days. The adults are mostly
congregated on the lower branches and trunk.
v Damage:
Mango hoppers are the most destructive pest of fruit trees. Injury to the
inflorescence and young leaves is caused by egg laying and feeding. The
voracious feeding nymphs are particularly harmful. They cause the inflorescence
to wither and turn brown. Even if the flower is fertilized the subsequent
development and fruit setting may cease. In thick and protected garden where
the atmosphere is humid a sooty mould develops on the patches of honey dew
exuded by the nymphs. The growth of young stem is much retarded and the older
branches do not bear much fruit. Damage to the mango crop as high as 60%.
Life stages of mango hopper ( Idioscopus clypealis)
v Management:
i.
Do not go for high density planting as it
provides favorable condition for hopper multiplication.
ii.
Do not encourage plants to put intermittent
flushes by regular irrigation and split doses of nitrogenous fertilizers.
iii.
Avoid water logged and damp condition.
iv.
Spray 2.5 kg of carbaryl 5WP or 2 liters of malathion 50EC or 1.5
liters of endosulfan 35EC in 1250 liters of water per ha. Once in February and
again in March.
v.
Spraying with Malathion LVC @ 1.4 liters per ha.
With aerial or ground equipment is also effective.
v Mango mealy-bug: (Dorsicha
mangifarae)
Hemiptera: Margarodidae
v Geographical distribution:
The mango mealy-bug is widely distributed in indo-gigantic plains from
Punjab to Assam. Beside the mango, it also attacks 62 other plants; include
such trees as the jack fruit, banyan, guava, papaya, citrus and jamun.
v General body characters:
Damage
is caused by nymph and wing less female which are oval, flattened and has body
covered with white mealy powder. The males have one pair of wings and are
crimson red.
v Life cycle:
This pest is active from December to May and spends rest of the year in
the egg stage. The eggs are generally deposited in April-may in soil up to 15cm
with in silken purses the dead body of the female is often round stiken to the
them. In the cervices or in loose soil, the egg purses may be found as deep as
60cm.
Severe infestation of mango mealy-bug on mango tree
The eggs are 1mm long and 0.7mm broad,
oval shiny pink when newly laid and paler brown later on. On emergence 70-80%
of nymphs ascend the trees immediately. The remaining 20-30% wandering around
feeding on weeds and the general undergrowth in the orchids. The mating takes
place after emergence. The males fly in large numbers. The female matures in
15-35 days and lay eggs for 22-47 days during April- may.
v Damage :
Only the nymphs are destructive and they suck plant juice, causing
tender shoots and flowers to dry up. The young fruits also become juice less
and drop off.
The pest is responsible for
causing the considerable loss to the mango growers and when there is a serious
attack the trees retain no fruit at all.
v
Management :
i.
Remove weeds from orchids which act as
additional hosts for mealy-bug.
ii.
Ploughing of orchids during summer exposes eggs
to the natural enemies and the extreme sun heat.
iii.
Nymphs should be prevented from crawling up the
trees by applying 15-20 cm white sticky bands with alkathene or plastic sheets
around the trunk about one meter above the ground level during 2nd
week of December.
iv.
The nymphs found congregating below the lower
bands of alkatehne should be killed mechanically or by applying 50g of methyl
parathion 2 percent dust.
v Mango stem-borer: (Bactocera rufomuculata)
Coleoptera: carambycidea
v Geographical distribution:
Both these species B.
rufomuculata and B. rubus is most
serious pest of mango in India. They have been recorded as serious pest of
mango, fig and other trees in north-western part of the Indian sub-continent.
v General body characters:
The full grown larvae
are stout, yellowish white, freshly grub measure about 6cm in length. Its head
is dark with strongly grown mandibles. The adults are long corn beetles, well
built, large and pale grayish measuring about 5cm in length and 2cm in breadth.
The beetle has long legs and antenna and a dirty white band extending from the
head to tip of the body each side. Number of yellowish dirty spots present on
elytra.
v Life cycle:
The life cycle is prolonged and adult is generally appear in monsoon.
They deposit eggs under the loosen bark in a wounded or diseased portion of the
trunk or branch. Winter is passed in grub stage in that very burrow. The larval
stage probably last more than a year and the pupal stage lasts about one month.
The life cycle may be completed in 1-2 years.
Adult Mango stem borer
v Damage:
Although the borer is not very common, yet whatever it appears in the
main trunk or branch, it invariably kills the host. Though the external
symptoms of attach are not always visible the site can be located from the sap
or frass that comes out of the hole. The mango stem- borer is also found in
newly fallen trees.
v Management:
i.
Cut and destroy the branches which are infested
by grubs and pupae.
ii.
Remove the frass near the holes on main stem and
inject 4ml of methyl parathion 50EC mixed in one liter of water in to the hole
and plug it with mud. Incase these holes open these may be treated again.
- Mango stone weevil: (sternochetus mangiferae)
Coleoptera: Curculionidae
v Geographical distribution:
Recorded in India
as a pest of mango crop. The export of mango fruits from India to USA has been
banned to prevent the entry of this weevil.
v
General body
characters:
This is short
stoutly build, ovoid, dark brown weevil which is found inside the mango fruit
or in its pulp.
v Life cycle:
The pest is
inactive from July-august onwards when they remain concealed in the soil or underneath
the bark of mango trees. They become active as soon as formation of fruit takes
place.
Infestation caused by the mango stone weevil grub
The weevils
lay egg in the skin or ripening fruit. The wound cause the ovipositor heals
soon and the fruit does not exhibit any sign of outward infestation. On
emergence from the egg the grub moves further inward, eating its way through
the unripe tissue until it bores to the embryo of the mango stone. When full
grown the larva form a cell inside the stone in which it pupates. The weevil
cuts its way through the stone and the sap comes out. The generation is
completed in 40-50 days and the adult become inactive and resume breeding only
in the next season. Thus, there seems to be only one generation in a year.
v Damage:
The insect
attacks mango verities with a relatively soft flesh. The injury caused by the
larva feeding in pulp sometimes heals over but certain number of fruits always
gets spoiled when the weevil makes exit through the ripe mango.
v Management
:
i.
The pest can be suppressed by destroying all the
fallen fruits, weevil mangoes and by disposing off refuse, stone, debris etc.
ii.
The weevil being an internal feeder through its
development is not amenable to control with any of the insecticide.
iii.
Raking of soil below the tree in October/
November and March can contribute partially to the weevil management.
v Mango fruit fly: (Bactrocera dorsalis)
Diptera: Tephritidae
v Geographical distribution:
The mango fruit fly or oriental fruit fly is the most serious pest of
all the fruit flies recorded in India and south-east Asia. It is also recorded
in Malaysia, Indonesia, Formosa, Philippine, Australia and Hawaii Island. Apart
from mango the pest also feed on peach, guava, chikh, cherry, and other citrus
plant totaling more than 250 hosts.
v Body characters:
The largest
maggot when full grown measures 8-5mm long and 1.5mm across the posterior end
and are yellow and opaque. The adult is stout a little larger than an ordinary
house fly and measures 14mm across the wings and 7mm along the body length. It
is brown and has almost transparent wings with yellow legs and dark rust- red
and black patterns on the thorax.
v Life cycle:
This pest is
active during the summer months and passes the winter as a hibernating pupa in
the soil.
The adult
flies emerge in April and starts feeding on guava, loquat, brinjal, chilies etc
later they shift on mango. These flies are most active in garden when the
temperature is in between 25-30°c. and
inactive below 20°c. The adults live for 4 months and feed on the exudation of
ripe fruits and on honey dew of various insects. Mating takes place at dusk and
lasts for about one hour. When flies are 10-15 days old they lay 2-15 eggs in
clusters at a time, 1-4mm deep in the soft skin of fruit, with the help of
sharp ovipositor. A female laid an average 50 eggs but under favorable
conditions 150-200 eggs laid in one month. The eggs hatch in 2-3 days in march-
April and 1-1.5 days in the summer and 10 days during winter. The maggots
development complete in to three stages and full grown in 6-29 days. In pupal
stage they burry themselves in the soil 8-13cm deep below the surface. The life
cycle is completed in 2-13 weeks and many generations are completed in a year.
- Damage:
Maggots are
very destructive and cause losses to all kinds of fruits. The infested fruits
become unmarketable and at time almost all contain maggots.
v Management:
i.
Avoid infestation of fruit fly by early harvest
of mature fruits.
ii.
To prevent the carryover of the pest destroy all
the fallen infested fruits twice a week.
iii.
Plough round the trees during winter to expose
and to kill the pupa.
iv.
Monitor the fruit fly population by using methyl
eugnol traps.
v.
Spray 1.25liters Malathion 50EC+12.5kg gur or
sugar in 1250liters of water per ha. And repeat spray in 7-10 days interval if
infestation continues.
vi.
After harvest dip the fruit in sodium chloride
solution for 60 minutes to kill the eggs, if any and also to decontaminate from
the pesticide residue if at all present.
v
Mango shoot bore: (Chlumetia transversa)
Lepidoptera:
Noctuidae
v General
body characters:
The adult is small grayish brown moth. Young caterpillars are orange
yellowish in color with characteristics dark brown prothoracic shield. Full
grown caterpillars are dark pink with dirty spots.
v Life
cycle:
Eggs are laid singly on tender leaves and they hatch in 2-3 days.
Freshly hatched caterpillars bore in to mib rib of tender shoots near the
growing point tunneling downwards and throwing their excreta out of entrance
hole. Larvae have five instars completed in 11-13 days. The full grown larva
enter in to slits and cracks under the bark of the tree. Soil pupation for
12-15 days. The life cycle occupies 30-42 days.
v Damage :
The damage is done by the larva by boring in to the growing shoots.
Leaves of effected shoots wither and drop down. Young grafted seedlings are
severely affected and may even be killed.
v Management
:
i.
Remove and burn the dried shoots.
ii.
Spray the new growth with 1.75 liters of
endosulfan 35 EC in 1250 liters of water per ha.
v Mango bud
mite: (aceria mangiferae)
Acari: Eriophidae
v Geographical
distribution:
The bud mite
is the pest of mangoes not only in India but also in Pakistan and USA. In India
the mite is serious particularly in Punjab, Haryana, and Uttar pardesh.
v Life cycle:
The detailed
life history of this mite is not has been studied much so far. Some observations on population dynamics have
revealed that there is a particular variation in the population. The population
dynamics changes with change in the environment.
v Damage :
The bud mite sucks the sap from onside the buds and causes necrosis of
tender tissues. When the population is high the entire bud may be killed. This
mite infests all verities of mango and none has shown resistance to it.
v Management :
i.
Remove and destroy all the panicles bearing
infested inflorescence.
ii.
Spray 1liter of dimethoate 30EC, in 1250 liters
of water per ha, preferably during summer.
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