Onion (Allium cepa L.)
Head borer (Helicoverpa armigera)
Symptoms
- The larva of this insect cuts the pedicel of the flower and feeds on the stalk.
- Single larva damages many flower stalks.
Management
- Collect and destroy the infected fruits and grown up larvae.
- Setup pheromone trap with Helilure at 12/ha for monitoring pest population.
- Grow simultaneously 40 days old American tall marigold as trap crop and 25 days old tomato seedling at 1:16 rows.
- Deep summer ploughing to expose the pupae to the sunlight and natural enemies.
- Monitoring of top three leaves for egg laying
- Ocimum/Basil acts as repellent plants
- Setting up light traps @ 1/acre for adults
- Erecting of bird perches @ 40/acre for encouraging predatory birds such as king crow, mynah, drongo etc.
- Release Trichogramma pretiosum@ 1 lakh nos. /ha/release at an interval of 7 days starting from flower initiation stage based on ETL of 10% damage.
- Spray HaNPV@ 250LE/ha at 28, 35 and 42 days after transplanting.
- Spray Bacillus thuringiensis (2 gram/litre).
- Spray of NSKE @ 4.0 per cent
- Natural enemies like Campoletis chloridae, Bracon brevicornis and Trichogramma spp are active in nature
Chemical Control
| Sl.No | Generic Name | Trade Name | Color code | Dosage/litre | Knapsack Sprayer (Capacity 10L) | Recommendation | Remarks | |
|---|---|---|---|---|---|---|---|---|
| Dosage/acre (200 L) | Dosage/hectare (500 L) | |||||||
| 1 | Cyantraniliprole 10.26% OD | Benevia | Green | 2 ml/ litre of water | 20 ml | 400 ml | 1000 ml | - |
| 2 | Chlorantraniliprole 18.5 SC | Coragen | Green | 0.3 ml/ litre of water | 3 ml | 60 ml | 150 ml | - |
| 3 | Flubendiamide 20 WG | Fluton, Takumi | Green | 0.2 ml/ litre of water | 2 ml | 40 ml | 100 ml | - |
| 4 | Indoxacarb 14.5 SC | Avaunt, Doxagan, Fego Challenger, Heroxa JK Indoxa, Inlay, Sarvada King Doxa, Tag Power | Yellow | 0.8 ml/ litre of water | 8 ml | 160 ml | 400 ml | - |
Extremely Toxic
Highly Toxic
Moderately Toxic
