Plant
protection
Pests
Mango hopper
(Tenemanchu purugu) (Idioscopus clypealis , Idioscopus nitidulus Amritodus atkinsoni )
Damage is caused by sucking sap from
tender leaves and inflorescence. Ovipositional punctures also cause damage to
tender leaves and inflorescence. Severely infested leaves become curled and inflorescence
gets dried. Affected parts are covered with honeydew and sooty mould.
Control
One spray with carbaryl @ 3
gms/litre of water in November before panicle
formation ensuring that tree trunks are also thoroughly drenched
during the spray. During full length stage of panicle but before full bloom
full bloom stage spraying with endosulfan @ 2 ml /litre of water or Dimethoate
@ 2 ml /litre of water or imida cloprid @ 0.3 ml/ litre of water if incidence
of hoppers is high (more than 5-10 per panicle).After fruit set at pea size
stage spraying with imida cloprid @ 0.3 ml/ litre of water or thiamethoxam @
0.4 gm/ litre of water.
Mealybug (Drosicha
mangiferae, Rastrococcus iceryodies)
Nymphs and adults suck the plant sap
and reduce the vigor of the plant. Excessive and continuous draining of plant
sap causes wilting and finally drying of infested tissue. They also secrete
honey dew, a sticky substance, which encourages the development of a fungus Maliola
mangiferae, resulting in sooty mould. R iceryodies is serious in South India .
They are considered more important because if the control measures are not
taken timely, the crop may be destroyed completely.
Control
Plough orchard during summer to expose eggs to natural
enemies and sun heat. Remove weeds like Clerodendron
infortunaturm which are additional hosts.
After mud plastering 25 cm width 400 gauge alkathene sheet may be
fastened to the tree trunk 30 cm above the ground level in the month of
December- January or use at sticky band on tree trunk to prevent migration of
crawlers from soil to trees, one week before their emergence.
Raking the soil around the tree trunk and mixing of
chlorpyriphos (1.5% dust) @250 gm per tree. The dust may also be sprinkled
below the alkathene band on the tree.
Spray NSKE 4% or crude garlic oil 1% or Dimethoate 0.06
% or Acephate @ 2 gm/lt or Spirotetramat @ 0.3 ml/lit of water
Shoot Borer (Chlumetia
transversa)
It causes serious damage to new flush of mango. The
affected shoots wilt droop and finally get dried. The infested trees become
stunted in growth and the shoot into which this larva is bored dies and does
not flower subsequently flowering is inhibited. Young trees up to the age of
8-10 years are more damaged.
Control
Do not retain minor flushes during off season. Apply
relatively higher dosage of potash. Prune the infested the shoots and burn.
Spray at bud – sprouting stage with Carbaryl 0.1 % followed by Dimethoate 0.04%
or Quinalphos 0.5% at 15 days interval from commencement of new flesh.
Stem Borer (Kaandam tolughu purugu) Batocera rufomaculata
Damage is caused
by the grub of this beetle as it feeds inside the stems, boring upwards and
resulting in drying of branches and in
severe cases attacked tree is killed.
Grubs with robust body feeding on inside tissues will be observed when
there is severe infestation.
Control
The grubs can be extracted through
hooked wires and then destroyed. Sthe insect can be controlled by injecting in hole 0.02%
dichlorvos ( DDVP) or 0.05% endosulphan @ 5 ml/holes or Celphos (aluminium
phosphate) one tablet (3g) per hole and
then holes may be sealed with mud .
Stone or Nut Weevil (Sternochaetus
mangiferae, S.frigidus )
It is a common pest of mango in southern India Assam and Bengal .
Sweeter varieties such as Alphonso, Bangalora, Neelum, etc. are more
prone to attack by this pest. Female lays eggs on the epicarp of partially
developed fruits or under the rind of ripening fruits. Newly emerged grubs bore
through the pulp, feed on seed coat and later cause damage to cotyledons. Pupation
takes place inside the seed. Discolouration of the pulp adjacent to the
affected portion has been observed. Eggs are minute and white in colour. Adult
weevils are 5 to 8 mm long, stout and dark brown in colour. Life-cycle is
completed in 40 to 50 days during June-July. Adults hibernate until the next
fruiting season. There is only one generation in a year. Extent of damage in
susceptible cultivars like Neelum, Totapuri and Banganpalli varies from 60 to
65 %.
Control
Collect fallen infested fruits and destroy. Spraying of
apply sticky band at upper end of the trunk to prevent migration of weevils to
branches for egg laying on fruits during February- March. Keep the tree basins
clean to prevent hiding of diapausing weevils. Spray during of season (December
– January) on tree trunk up to 2m height with fenthion 0.05%or Carbayl 0.1% or
Deltamethrin 00025% six weeks after fruit set (especially at marble stage) and
second spray may be given after 15 days.
Thrips (Rati Mangu) (Thrips
hawaiiensis, Scirtothrips dorsalis)
Thrips appear during flowering and
fruiting stages where their infestation can be recognized during January on
flowers and developing fruits causing ‘Mangu’ though initial infestation result
in flower drop. Their impact on young fruits are seen in terms of rough surface
as well as deshaping of fruits.
Control
It can be controlled by spraying thiamethoxam @ 0.4 gm / litre of water
or acephate 1.5 ml/lt of water or fipronil 2 ml / lt of water.
Leaf Webber (Orthaga
euadrusalis)
The infestation is severe in shady
conditions. Old orchards with lesser space between tree canopies have more
infestation than open orchards. The larvae of Orthaga spp web the leaves and the terminal shoots into clusters
which harbor several of them in the initial stage. The larvae are gregarious in
the beginning and feed by scrapping the leaf surface. Late instar larvae feed
on whole leaf lamina leaving only midrib. Severs attack leads to drying of
shoots / branches and reduction in fruit yield.
Control
Supervise the orchard once in a month
and search for webbed shoots. Prune the infested shoots and destroy them along
with larvae during April – July. After pruning 2 to 3 sprays starting from last
week of July at 15 days interval with Carbaryl 0.2% or quinalphos 0.05% have
been found effective in controlling the pest.
Shoot gall psylla (Apsylla
cistellata)
It is a very serious pest of mango in many parts of India , particularly in Terai region of U.P., North
Bihar and West Bengal . This pest creates green
conical galls in leaf axis. The activity of the pest starts from August. The
galls dry out after emergence of psyllid adults in March. The galls are usually
seen during September-October. Consequently, there is no fruit set. There is
only one generation of the pest in a year.
Control
The galls with nymphs inside should be
collected and destroyed to prevent carryover of the pest. The pest can
effectively be controlled by spraying monocrotophos (0.05%) or dimethoate
(0.06%) or quinalphos (0.05 %) at 2 week intervals starting from the middle of
August. The use of same chemical for every spray should be avoided.
Mango fruit borer (Deanolis albizonalis)
In coastal Andhra Pradesh the
incidence of mango fruit borer is slowly increasing and assuming as a serious problem on mango in some areas.
The incidence is found right from pea size upto maturity stage. In initial
stages upto 6-10 larvae are found in one fruit. fruits in one bunch are prone
to attack due to migration of grown up larvae
to neighboring fruits as in case of nut weevil Newly emerged larvae
bore through the pulp, feed on seed coat and later cause damage to
cotyledons.
Control
- After mango harvest removal of Dead wood from
the tree
- Removal of diapausing stage of Mango fruit borer
from cracks and crevices in the bark and dried twigs
- Removal and destruction of damaged and MFB
infested fruits especially at pea and marble stages of the fruit
- In Second fort night of
January spray of chloripyriphos 2.5 ml or dichlorovas 1.5 ml or
carbaryl 3 gms per litre of water especially in those garden where
previous incidence of this recorded. Repeat spray of chloripyriphos 2.5 ml
or dichlorovas 1.5 ml or carbaryl 3 gms or Neem oil 3ml + chloripyriphos 1
ml per litre of water at marble stage of the fruit. The sprayings should
be preferably carried out during evening hours
- Spraying of NSKE 5 % at 10 days interval during the months of April
and May upto 15 days before harvest
Red mite (Erra
nalli) (Oligonychus mangiferous)
These mites both in nymphal and adult stages infest
mango leaves. Their presence reflects in terms of scrapped chlorophyll
resulting in yellowish tinge on upper side and white webs on underside of leaf.
Control
It can be controlled by spraying wettable sulphur 3gm/ litre of water or diafenthiuron 1 ml /lt of water.
Diseases
Powdery midew ( Budida Rogam) Oidium mangifere
Powdery mildew is one of the most
serious diseases of mango affecting almost all the varieties, Some times, as
high as 70-80 per cent crop loss has been recorded on individual plant basis.
The
characteristic symptom of the disease is the white superficial powdery fungal
growth on leaves, stalks of panicles, flowers and young fruits. The affected
flowers and fruits drop pre-maturely reducing the crop load considerably or
might even prevent the fruit set. Rains or mists accompanied by cooler nights
during flowering are congenial for the disease spread. The fungus parasitizes
young tissues of all parts of the inflorescence, leaves and fruits.
Control
Following
three sprays of fungicides at 15 days interval recommended for effective
control of the disease Wettable sulphur 3-4 g/lit of water or Calixin 1 ml/lit
or 1 ml Karathane / lit. water).
Anthracnose (Macha Rogam) Colletotrichum gloeosporiodes
The anthracnose disease is of
widespread occurrence. The disease causes serious losses to young shoots,
flowers and fruits under favourable climatic conditions of high humidity,
frequent rains and a temperature of 24-32oC. It is also affects
fruits during storage. The disease produces leaf spot; blossom blight,
withertip, twig blight and fruit rot symptoms. Tender shoots and foliage are
easily affected which ultimately cause die back of young branches. Older twigs
may also be infected through wounds which in severe cases may be fatal.
Black
spots develop on panicles as well as on fruits. Severe infection destroys the
entire inflorescence resulting in no setting of fruits. Young infected fruits
develop black spots, shrivel and drop off. Fruits infected at mature stage carry
the fungus into storage and cause considerable loss during storage, transit and
marketing. The fungus perpetuates on twigs and leaves of mango or other hosts.
Control
Dead twigs should be pruned to reduce inoculum potential
Trees may be sprayed twice with Carbendazim @ 1g/lit or Thiophenate methyl
1g/lit at 15 days interval during flowering to control blossom infection.
Spraying of copper fungicides (0.3%) is recommended for the control of foliar
infection.
Bacterial canker (Xanthomonas campestris pv. mangiferaeindicae)
The disease causes fruit drop
(10-70%), yield loss (10-85%) and storage rot (5-100%). Many commercial
cultivars of mango including Langra, Dashehari, Amrapali, Mallika, and Totapuri
are susceptible to this disease. The disease is found on leaves, petioles,
twigs, branches and fruits, initially producing water-soaked lesions and later
turning into typical cankers. The disease first appears as minute water-soaked
irregular lesions on any part of leaf or leaf lamina. The lesions are light
yellow in colour but with age, enlarge and turn dark brown to black. They
become angular, cankerous and raised, and are surrounded by chlorotic halos.
Several lesions coalesce to form irregular necrotic cankerous patches. In
severe infections the leaves turn yellow and drop off. Cankerous lesions appear
on petioles, twigs and young fruits. The water soaked lesions also develop on
fruits which later turn dark brown to black. They often burst open, releasing highly
contagious gummy ooze containg bacterial cells. The fresh lesions on branches
and twigs are water soaked which later become raised and dark brown in colour
with longitudinal cracks but without any ooze.
Control
Control
- Seedling
certification, inspection and orchard sanitation.
- Three
sprays of streptocycline (100 ppm) or Agrimycin-100 (100 ppm) after first
visual symptom at 10-days intervals.
- Monthly
sprays of Bavistin (1000 ppm) or copper oxychloride (3000 ppm) were also
found effective.
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