Onion (Allium cepa L.)
Onion yellow dwarf disease(Onion Yellow Dwarf Virus)
Symptoms
- The disease is characterized by severe stunting of the plants, and dwarfing and twisting of the flower stalk.
- The affected leaves and stems change their normal green colour to various shades of yellow and leaves tend to flatten and crinkle and as a result bend over.
- Mild chlorotic stripes to bright yellow stripes, mosaic, curling of leaves and stunted growth.
- It is transmitted mechanically as well as by insect vectors.
Management
- Removal and destruction of the diseased plants check the spread of the disease.
- Healthy bulbs should be used for seed production.
- Follow crop rotation of at least three years.
- Use blue sticky trap.
- Conserve the predators such as coccinellids, lacewings, spiders, wasps etc. for controlling thrips.
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 | Dimethoate 30 EC | Nugor, Rogor, Tagor, Tara 909, Label colour | Yellow | 1 ml/ litre of water | 10 ml | 200 ml | 500 ml | Against vecters |
Extremely Toxic
Highly Toxic
Moderately Toxic
