The cabbage borer, also known as the cabbage webworm or the spotted bollworm (scientific name Hellula undalis), is a moth species that is a major pest of cole crops, including cabbage, broccoli, cauliflower, kale, and kohlrabi. The larvae of the moth are the damaging stage, and they tunnel into the leaves, stems, and heads of the plants, causing extensive damage and reducing yields.
- Type of Infestation: Pest
- Common Name: Cabbage Borer pest
- Causal Organism: Hellula undalis
- Affected Parts Of the plant: Leaves, Stem and Head
Identification:
- Adult moths are pale yellow-brown with wavy grey lines on their forewings.
- Larvae are pale whitish-brown with 4-5 purplish-brown longitudinal stripes.
- Eggs are yellowish-white and oval-shaped.
Environmental favorable factors for pests/Diseases:
- Temperature: The optimal temperature range for cabbage borer development is between 20-30°C (68-86°F). Warmer temperatures accelerate life cycles, leading to more generations per season and higher overall populations.
- Humidity: While extremely high humidity can hinder larval development, moderate humidity levels (50-70%) provide favorable conditions for egg laying, hatching, and larval survival.
Symptoms of Pest/Disease:
- Webbing: The larvae spin silk webs on the leaves and stems of the plants. This webbing can be a good indicator of the presence of borers, even if you haven't seen the larvae themselves.
- Holes: The larvae bore into the leaves, stems, and heads of the plants, creating irregular-shaped holes. These holes can be small or large, and they may be filled with frass (the excrement of the larvae).
- Wilting: As the larvae feed on the plant tissue, the plant may start to wilt. This is especially noticeable in hot weather.
- Stunted growth: If the infestation is severe, the plants may be stunted and fail to produce heads.
- Discoloration: The leaves of infested plants may turn yellow or brown, and they may have brown or black spots.
Measures to control Pests/Diseases:
Products | Technical Names | Dosages |
EMA5 | Emamectin benzoate 5 % SG | 80-100 grams per Acre |
Fluben | Flubendiamide 39.35 % sc | 60ml/acre |
AAKRAMAK PLUS | Novaluron 5.25% + Indoxacarb 4.5% SC | 2 ml / Lit |
CHLORO 20 | Chloropyriphos 20 % EC | 500 to 1200 ML Per Ac |