Brinjal Shoot and Fruit Borer: Life cycle, Damage, Management
Common Name: Brinjal Shoot and Fruit Borer Scientific Name: Leucinoides orbonalis Order: Lepidoptera Family: Pyralidae
Brinjal shoot and fruit borer is one of the serious pests in brinjal. Adult is medium sized moth with forewings having black and brown patches and dots on white color wings. Hind wings are opalescent with black dots. Larva is soft, fleshy and pink in color. Eggs are creamy white and Pupa is grayish colored boat shaped cocoon.
Life Cycle of Brinjal shoot and fruit borer
The adult lays eggs on leaves, flower and fruits. Within about a week they hatch into larvae. Upon hatching they start boring from the tender shoots and feed on the stem and inside the fruits. There appears wilting in the damaged shoot. In severe infestation the growing points are killed. Full grown larvae come out of their feeding tunnels and pupate in tough silken cocoons among the fallen leaves which again enter into adult. In epidermis, the loss may ranges above 50% however early and heavy rain may lower down the attack to a great extent.
Damage of Brinjal shoot and fruit borer
Larva is most destructive and bore in to the terminal shoots in young plants, causing withering of terminal shoots. Heavy infestation leads to drying of leaves due to boring of petioles, shedding of flower, buds. Boring of larvae on fruits causes fruit rotting and loss of yield. Fruits are found with bore holes, holes are filled with larval excreta. Adults are medium size marked with black and brown patches on forewing.
Management of Brinjal shoot and fruit borer
- Destruction of infested stems, fruits and fallen leaves from the orchard.
- Crop rotation, Solanaceous crop year after year in the same field cause increased infestation. Eggplant varieties with round type of fruits are much susceptible to EFSB so grow slender type of fruits (Neupane, 2000).
- Use nylon net barrier in nurseries to prevent spreading of insect from nursery to main field.
- Grow location specific eggplant varieties moderately tolerant to EFSB such as Pusa Kranti and Nurki at the Kathmandu valley, Lurki at Baglung and Parbat areas, Pusa long at Dhading, green long and Pusa Kranti at Tarahara areas of Sunsari.
- Cut and destroy wilted and borer damaged plant parts during pre-flowering and flowering period at weekly intervals.
- Collect and destroy borer infested flower buds and fruits during each harvest to prevent migration of caterpillar from fruit to fruit.
- Transplant eggplants in early June to minimize losses by shoot and fruit borer (Leucinodes orbonalis) in Kathmandu valley condition.
- Grow barrier crops such as maize around the eggplant crop field.
- Adopt clean cultivation practices.
- Avoid continuous cropping of eggplants in the same field.
- Grow EFSB moderately tolerant eggplant varieties, such as Green long, Pusa Kranti, Pusa purple long PBR 129-5, 517-4, H-128, H-129.
- Install pheromone trap with Lucin-lure for monitoring of male moth. 3-4 moths per traps indicate to start management operation.
- Create physical barrier using nylon net of 2m high and cover the eggplant field to check the entry of moths into the healthy field from infested field.
- Release Trichogramma chilonis in the crop field @ 250000 parasitized eggs per ha @ 50,000 release for 5 times at weekly intervals, starting from flowering.
- Spray crude Neem seed extract @5% or Neemarin (Azaardiractin 0.03%) @ 5 ml per litre water.
- Spray Bacillus thuringiensis (Bt) based commercial formulations such as DIPEL or BIOLEP @ 3gm per ltr in the evening hours at 10 days interval.
- Spray chemical insecticides such as Thiodine 35% EC (endosulfan) @ 1.5 ml per ltr of water to manage borer.
- Spray 0.07% solution of endosulfan 35% EC at 10 days interval, or seed kernel extract (NKSE) @5 gm grinded powder/ ltr water or 0.07% solution of Dipel (Bacillus thuringiensis)