TNAU Agritech Portal
Home | About Us | Success Stories | Farmers Association | Farmers' Innovation | Publications | Contact

Crop Protection :: Pests of Cucurbits

Greasy Cutworm/ Black cut worm: Agrotis ipsilon
Symptoms of damage
  • Young larvae feed on the epidermis of the leaves.
  • Older larvae come out at night and feed young plants by cutting their stems
  • They also damage the tubers by eating away part of them.

Identification of pest
Eggs
  • Creamy white, dome-shaped eggs, laid singly on lower surface of the leaves
Larvae
  • Newly emerged young larva is yellow in colour
  • The full-grown larva is dark or dark brown with a plump and greasy body.
Pupa
  • Dark brown pupae are found in earthen cells lying underground in the potato fields.
Adult Moth
  • Dark with some grayish patches on the back and dark streaks on the forewings.
Larva

Adult


Management
  • Flood the infested fields.
  • Hand –pick and destroy the larvae – morning and evening hours on cracks and crevices in the field
  •  Plough the soil during summer months to expose  larvae and pupae to avian predators
  •  Set up  light trap @ 1/ ha
  •  Pheromone traps @ 12/ ha to attract male moths
  • Spray insecticides like chlorpyriphos 20EC @ 1 lit/ha or neem oil @ 3%

Top


Potato tuber moth: Phthorimaea operculella
Symptoms of damage
  • It is a pest of field and storage
  • Larva tunnels into foliage, stem and tubers
  • Galleries are formed near tuber eyes
Potato tuber moth infested tuber

Potato tuber moth infested tuber

Potato tuber moth Infested leaves


Identification of pest
  • Egg - laid singly –the ventral surface of foliage and exposed tubers.
  • Larva - Yellow coloured caterpillar with dark brown head.
  • Pupa: Pupation occurs within a cocoon among the trash, clods of the earth in the field.
  • Adult: Small narrow winged moth, greyish brown forewings and hind wings- dirty white.
Larvae

Adult


Management
  • Select healthy tubers
  • Avoid shallow planting of tubers. Plant the tubers to a depth at 10 - 15 cm deep.
  • Install pheromone traps at 15/ha.
  • Collect and destroy all the infested tubers from the field
  • Do not leave the harvested tubers in the field overnight
  • Adopt intercropping with chillies, onion or peas
  • Do earthing up at 60 days after planting to avoid female moths laying eggs on the exposed tubers
  • Cover the upper surface of potato tubers with the branches of Lantana and Eupatorium  to repel the ovipositing moth in the godown
  • Release egg larval parasitoid: Chelonus blackburnii @ 30,000/ha twice – 40 and 70 day after planting
  • Spray NSKE @ 5% or quinalphos 25 EC @ 2ml/lit of water to manage foliar damage
  • Spray Bacillus thuringiensis @ 1 kg /ha at 10 days interval

Top


White grubs: Holotrichia sp.

Symptoms of damage
  • Grubs feed on roots and tubers

Identification of pest
  • Larva:  
    ‘C’ shaped grub 
    Adult
    Brown beetle with pale prothorax

Management
  • Summer ploughing to expose pupae
  • Quinalphos 5% Dust @ 25 kg/ ha – 10 days after first summer rain
  • Set up light trap @ 1/ha between 7 PM and 9 PM
  • Hand – pick adult beetles in the morning.

Top


Tobacco Caterpillar: Spodoptera litura

Symptoms of damage
  • The young larvae first feed gregariously and scrape the leaves.
  • Older larvae spread out and may completely devour the leaves resulting in poor growth of plants.

Identification of pest
  • Egg: -masses appear golden brown
  • Larva: - pale greenish with dark markings
  • Gregarious in the early stages
  • Adult
    • Forewings – brown colour with wavy white marking
    • Hind wings-  white colour with a brown patch along the margin
Larva

Adult


Management
    • Plough the soil to expose and kill the pupae
    • Grow castor along border and irrigation channel as trap crop
    • Flood the field to drive out the hibernating larvae
    • Set up light trap @1/ha
    • Pheromone traps (Pherodin SL) @ 15/ ha to attract male moths
    • Collect and destroy egg masses in castor and tomato
    • Hand pick grown up larvae and kill them
    • Spray Sl NPV @ 1.5 X 1012 POBs / ha + 2.5 Kg crude sugar + 0.1 % teepol

    Poison bait

    • Rice bran 5 Kg + Molasses or Brown sugar 500g + Carbaryl 50 WP 500g+ 3lit of water/ha
    • Mix the ingredients well – Kept around the field in the evening hours
    • Spray chlorpyriphos 20 EC 2lit/ha or dichlorovos 76 WSC 1 lit/ha

Top


Green Leaf Hopper Empoasca kerri

Symptoms of damage
  • Tips of affected leaves become brown, turn upwards and get dried up

Identification of pest
  • Egg - elongated yellow-white egg is deposited in leaf vein.
  • Nymph - Pale – green, wedge shaped
  • Winged pads extend up to the fifth abdominal segment.
  • Adult
  • It is a wedge shaped and pale green insect


Management
  • Spray dimethoate 30EC or phosphomidon (Dimecron) 2ml/lit

Top


Green peach aphid: Myzus persicae

Symptoms of damage
  • Aphids suck sap of plants, as a result of which leaves turn pale and dry up.
  • This pest also transmits various viral to potato plants.

Identification of pest
  • It resembles wingless adult but the size is small.


Management
  • Spray dimethoate 0.3%

Top


Whitefly: Bemisia tabaci
Symptoms of damage
  • Nymphs suck sap from the leaves and lower their vitality.
  • Yellowing and curling of leaf
  • Sooty mould develops on affected leaves

Identification of pest
  • Egg

    • It is smooth, sub elliptical, stalked at broader basal end.
    • Its colour is light yellow, when freshly laid, turn dark brown later on.
    Nymph
    • Pale-yellow in colour

    Adult

    • It is small winged insect having light yellow
    • Wings are pure white and has prominent long legs.


Management
  • Well timed irrigation
  • Avoid common solanaceous crops in the endemic areas
  • Spray dimethoate 0.3%

Top


Home | About Us | Success Stories | Farmers Association | Publications | Contact Us

© 2015 TNAU. All Rights Reserved.