Major insects and control measures of Potato:

Major insects and control measures of Potato:

Potato is an important crop world wide. The yield of potato is greatly reduced due to

attack of several insect pest and diseases, including several viruses which contribute

to the degeneration of seed stocks. For better tuber crop production, good quality of

seed materials needs to be supplied to the farmers. So, emphasis should be given to

produce disease and insect free seed. Major insect pests of potato are Cutworm,

Potato tuber moth, Aphid, Whitefly and Leafhopper.

Potato cutworm (Agrotis ipsilon)

Cutworm is a polyphagous and the most devastating soil pest.

Yield is reduced up to 35- 40%by cutworm.Young caterpillars

feed on leaves and later on stems. Mature caterpillars cause

the most damage. They are capable of eating or destroying

the entire plant. Some times they cut-off young seedlings at

ground level during night. Caterpillars feed on tubers and

roots, boring a wide shallow hole.

Control measures:

• Hand picking of caterpillars at night by torch or very early morning.

• Flooding of the field for a few days before sowing can help to control cutworm

caterpillars in the soil.

• Potato crops grown for seed should be monitored closely and good sanitation

should be maintained.

• Use of poison bait by controlling cutworm.

• Use of insecticides Chlorpyrifos (Chlorpyrifos 48EC/Pyrifos 20EC @ 5ml/1L water

at 15 days interval)/Carbofuran (Dursban 20EC and Furadan 5 G @ 20 kg/ha.)

• Pheromone traps are used to monitor and catch moths of cutworms.

Potato cutworm

Potato Tuber Moth (Phthorimaea operculella)

Potato tuber moths (PTM) attack potato in

both field and storage.It causes 100% tuber

damage in the farmers field and home

storages. Small larvae usually enter the tuber

at the eyes. Frequently, the larvae feed just

below the surface of the potato leaving a dark

tunnel. The tunnels are filled with larval

excreta. Damage tuber attacked by bacterial infestation resulting potato tuber is rotted.

Control measures:

Pest incidence can be reduced through cultural practices such as –

• Controlling irrigation to prevent soil cracking that allows moths to reach the tubers.

• Hilling-up to properly cover the tubers.

• Harvested tubers are not left in the fields overnight; the heaps of tubers should be

covered with polythene sheet / dried straw/ cloth to laying egg on the seed tubers.

• Using pheromone traps to capture adult moth and monitor field populations.

• Likewise, repellent plants such as Minthostachys spp., eucalyptus, or lantana help

to protect stored tubers.

• The PTM damage can be reduced by dipping tubers in suspension of Phenthoat /

Deltamethrin at 2 ml/L of water for 15 minutes and then drying after shade

especially seed tubers.

Aphids

Green peach aphid: Myzus persicae

Potato aphid: Macrosiphum euphorbiae

Aphid colonies can be easily identified in plant terminal leaves and on the underside

of leaves and plant root in the field. As a result black sooty mould fungus that grows

on the honeydew produced by the nymphs will cover the plant. Due to severe

infestation, leaf become curl and finally dried

from upper portion of the plants.They also

appear in tuber sprouts in stores. Finally they

transmit viruses to seed potatoes.

Control measures:

• Foliar sprays of Neem seed extract (1 kg, half broken neem seeds are dipped into

10 litres water for 12 hours).

• Foliar spray of soap water @ 2gm /L of water at 3 days interval.

• Sticky yellow traps can be used for population level evaluation and control.

• Different predatory and parasitoid insects also feed on aphids.Common predators

are lady bird beetles and their larvae, green lacewing larvae, and syrphid fly larvae.

• Schedule spaying of insecticides such as-Melathion (Fyfanon 57EC, Malataf

57EC@ 2ml/1L of water)/Imidaclorpid (Admire 200 SL @ 0.5ml/1L of water)

should be monitored regularly.

Damage in field Damage in storage

Aphid affected laves Aphid Infected tubers

• Haulm pulling will be done for seed potato production.

• Rogue infected potato plants to reduce the incidence of viral disease infection

within a field.

White flies

(Aleurodicus disper, Bemisia tabaci)

Besides the presence of nymphs and adults on the underside of leaves, white flies

cause yellowing of infested leaves. Whitefly excretes honeydew covers the lower

leaves and supports the growth of black sooty mould,

which may coat the entire plant. Recently, potato apical

leaf curl virus has been reported and up to 100%

infection occurred in India. This virus transmitted

through white flies.

Control measures:

• Unnecessary use of insecticides should be avoided.

• Sticky yellow traps can be used for population level evaluation and control.

• Foliar sprays of Neem seed extract (1 kg, half broken neem seeds is dipped into 10

litres water for 12 hours).

• Foliar spray of soap water @ 2gm /L of water at 3 days interval.

• Monitor on schedule spray of insecticides such as-Melathion(Fyfanon 57EC, Malataf

57 EC @ 5 ml/1L of water) or Imidaclorpid(Admire 200SL@ 0.5ml/1L of water)

Leafhopper (Empoasca spp. and Amrasca spp.)

Besides the presence of nymphs and adults on the

underside of leaves, leafhoppers burn leaf edges with

top leaf roll and foliar yellowing. Plants may die

prematurely. Some species transmit mycoplasmal

diseases such as aster yellows and witches’-broom

disease.

Control measures:

• Avoid alternate host from the seed potato production fields.

• Use light trap for preventing infestation.

• Resistant or tolerant varieties can be used for controlling leafhopper population.

• Foliar spray of Neem seed extract (1 kg, half broken neem seeds is dipped into 10

litres water for 12 hours).

• Schedule spray of insecticides such as- Quinalphos (Corolux 25EC, Debiqueen

25EC and Kinalux 25EC @ 2 ml/L of water) and monitored regularly.

1.4 Harvesting and Seed preservation

Harvesting should be done at 80 to 90 days after sowing (depending on the varieties).

After curing, the potato tuber should be preserved in cold storage at 2.50- 40 C with

85-95 % Relative humidity (RH).

White fly

Leafhopper