Insect Pests of Vegetable, Ornamental and Spice Crops (2+1)

Brinjal shoot and fruit borer

1. Brinjal shoot and fruit borer, Leucinodes orbonalis (Pyraustidae: Lepidoptera)

Distribution: Indian sub continent, South Africa. Congo, Laos, Thailand and Malaysia.

Host plants:

• Most destructive pest of egg plant.
• Has also been reported from potato, and other solanaceous vegetables

Damage:

• Damages the crop from seedling stage till the harvest
• In young plants, the caterpillars result in dead hearts
• Later on they bore into flower buds and fruits
• Enter from under the calyx, seal the hole with excreta
• The damaged flower buds are shed without blossoming
• Fruits show circular exit holes.
• These fruits become unfit for human consumption and lose market value
• Infestation up to 70 per cent may be recorded

Identification:

• Eggs are flattened elliptical, 0.5 mm, creamy white
• Full grown caterpillars are 15-18 mm long and light pink in colour
• Moths are medium sized with white wings.
• Fore wings have conspicuous black and brown patches and dots.
• Hind wings are opalescent with black dots along the margins.
• Wing span is 22-26 mm.

Life cycle:

• A single female lays about 250 eggs
• Eggs hatch in 3-5 and 7-8 days during summer and winter, respectively.
• Larval duration is 12-15 days (summer) and 22 days (winter).
• Prepupal period is 3-4 days
• Pupal period lasts for 7-10 days during summer and about 15 days during winter.

Salient features:

• The pest remains active throughout the year in moderate climate
• Eggs are laid singly on ventral surface of leaves, shoots, flower buds and sometimes on fruits also
• Pupation takes place on stems or fruits in grey colours tough cocoons.
• Pest over winters in the larval stage.

Management:

• Avoid continuous cropping.
• Grow less susceptible varieties like Arka Kesav, Pusa Purple Round, Arka Kasumakar, Pusa Purple Cluster, Pusa Purple Long, Punjab Barsati, Kalyanpur 2, Punjab Chamkila
• Intercropping with coriander/ fennel as single row/ double row or border crop
• Collect all attacked shoots and fruits at regular intervals and burry them deep.
• Use sex pheromones @ 100/ ha (10x10m)
• Periodic releases of Trichogramma chilonis @ 100000 parasitised eggs/ha
• Bt formulations @ 500g/ha
• NSKE @ 4.0 per cent.
• Spray cypermethrin (0.01%) of fenvalerate (0.01%) or deltamethrin (0.0028%) or cartap hydrochloride (0.2%).
• Parasitoids like Trathala flavoorbitalis and Goryphus nursei are also active against this pest in nature.