Major pests of Onion are:-
1.Onion Thrips: Thrips tabaci
Symptoms of damage:
- Small white silvery patches are seen all over the leaves
- In severe infestation, leaves dry from tip to downward
Identification of pest:
- Eggs: Are laid only in the tender leaf
- Adult: The colour of the insect varies from pale yellow to grey.
Management:
- Clean cultivation, regular hoeing
- Flooding of infested field will check the thrips population.
- Spray insecticides dimethoate @ 0.06% or profenofos @ 0.05%
2.Onion Fly: Delia antiqua
Symptoms of damage:
- Its leaves get rotten, shredded and rolled up
- Growth of tubers gets hampered, tissues get decayed and becoming unfit for marketing
Identification of Pest:
- Egg: long whitish colour eggs are laid on the undersurface of onion near soil
- Larva: Whitish and adopous
- Pupa: Pupation takes place in soil
- Adult: Grey coloured fly
Management:
- Adopt proper crop rotation
- Spray malathion 1 lit/ha
3.Earwig: Euborellia annulipes
Symptoms of damage:
- Both nymphs and aduts bore into the onion bulb and feed.
Identification of pest:
- Eggs: are laid only in the tender leaf
- Adult: The colour of the insect varies from pale yellow to grey
Management:
- Soil application of Carbofuran 3 G at 30 kg/ha on 20 DAS and earthed up.
- Basal application of FYM 25 t/ha or 250 kg/ha of neem cake.
Source-
- TamilNadu Agritech Portal
