Friday, January 20, 2012

PESTS OF CHILLIES


PESTS OF CHILLIES
CHILLI THRIPS
Scirtothrips dorsalis
Caliothrips indicus
Frankliniella sulphurea
Thripidae: Thysanoptera
S. dorsalis is found in almost all chilly growing areas. It is a
polyphagus pest. Besides chilli, it also infests brinjal, cotton, groundnut,
castor, bottlegourd, guava, tea and grapevine. It is more common on unirrigated
chilli crop than irrigated one.
They are s lender, tiny, straw coloured insects with fringed wings.
A female adult inserts 40-48 white, minute eggs into veins.
Both nymphs and adults lacerate the leaf tissues and suck the oozing
sap, sometimes even the buds and flowers are attacked. Generally they
attack tender leaves and growing shoots. Rarely the older leaves are
attacked. Their damage results in
v The infested leaves curling upward, crumbling and shedding
v Infested buds turning brittle with petiole becoming brown and dropping
down.
v Affected fruits showing light brown scars.
Pest infestation is severe in dry weather. The damage ranges
between 30-50%.
One life cycle is completed on an average in 2- 2.5 weeks. There are
about 25 generations in a year. Reproduction in thrips is generally sexual,
parthenogenesis is also present.
MANAGEMENT
· Seed treatment with imidacloprid @ 3 -5 g/kg of seed.
· Foliar spraying with carbaryl 3g/l or phosalone 3ml/l or acephate 1 g/l
or fipronil 2 ml/l or spinosad 0.3 ml/l or diafenthiuron 1.2 g/l so as to
wet the undersurface of the leaves.
· Application of fipronil 0.3G 8 kg/acre at 15 and 45 days after
transplanting.
CHLLI POD BORERS
Spodoptera litura,S. exigua
Helicoverpa armigera; Noctuidae
Utetheisa pulchella; Arctiidae
Lepidoptera
Feeding by S. litura, S. exigua leads to irregular holes on the leaves
and fruits. Affected pods turn whitish and dry up. In fruits, seeds are also
eaten. Attack of H.armigera leads to round hole on fruits. In addition to
these borers, sometimes U. pulchella also feeds on the pericarp leaving
the seed intact. Ladder like marks are seen on chilli pod due to U.
pulchella . Their detailed history can be is given under pests of cotton and
millets (S. exigua ).
MANAGEMENT
1. Deep summer ploughing.
2. Monitoring with pheromone traps @ 4/acre
3. Raising trap crops like castor (S. litura ), marigold (H.armigera).
4. Spraying with SNPV/HaNPV at 250LE/acre in the evening.
5. Spraying novuluron 1.0 ml/l or diflubenzuron 1.0 g/l controls just
hatched larvae.
6. Foliar spraying of thiodicarb 1.0 g/l or acephate 1.5 g/l or chlorpyriphos
2.5 ml/l or spinosad 0.3ml/l or quinalphos 2 ml/l.
7. Poison baiting with rice bran 5 kg + chlorpyriphos 500 ml or carbaryl
500g + jaggery 500 g with water in the form of small balls in the
evening hours.
CHILLI APHIDS
Aphis gossypii, Myzus persicae
Aphididae: Hemiptera
They are polyphagous pests. Cloudy weather is very favorable for
multiplication of aphids. Heavy rains cause reduction in their population.
Adults are found in large numbers on the undersurface of leaves and
growing shoots of plants.
Both nymphs and adults suck sap and also excrete honeydew on
which black sooty mould develops affecting photosynthetic activity thus it
causing
v Retardation in growth and fruiting capacity of the plant.
v Sooty mould
Foliar spray with methyl demeton 1 ml/l or acephate 1.5 g/l is
effective.
CHILLI MITES
Polyphagotarsonemus latus
Tarsonemus translucens
Tarsonemidae
Tetranychus cinnabarinus
Tetranychidae: Acarina
A minor pest emerged as a major pest in recent past. The
infestation starts in the nursery after 40 days of germination. Severe
infestation is seen in transplanted crop of 2-3 months old. The tiny white
transparent mites are found in large numbers on the undersurface of
leaves under fine webs. Both nymphs and adults suck sap and devitalize
the plant causing ‘Murda’ disease of chillies. Infestation results in
v Downward curling of leaves,
v The affected leaves becoming inverted boat shaped,
v The leaves rolling down along the margin with elongation of petioles.
v Affected leaves turning dark green in certain cases.
v Younger leaves at the tip of branch clustering.
MANAGEMENT
· Foliar spraying of dicofol 5ml/l or wettable sulphur 3g/l.
· Synthetic pyrethroids not to be used.
· If both thrips and mites are noticed, spraying phosalone 3ml/l or
diafenthiuron 1.5 g /l or chlorfenapyr 2 ml/l.
CHILLI BLOSSOM MIDGE
Asphondylia capsici
Cecidomyiidae: Diptera
Fly is dark reddish brown mosquito like midge that lays eggs in
flower buds. Maggot is tiny pale orange colored and feeds on the floral
parts leading to poor development of fruits. The ovary is distorted into gall
like structure of varied shape.
Foliar spray with triazophos 2 ml/l or carbosulfan 2 ml/l followed by
chlorpyriphos 2.0 ml/l one week later is found effective.