Common crops affected
- Cucumber
- Melon
- Squash
- Pumpkin
What is it?
Diaphania larvae first feed on foliage — webbing and rolling leaves — then bore into developing fruit and shoots. Once inside the fruit they are protected, so early timing on foliar-stage larvae is key.
How to identify it
- Webbed, rolled or folded leaves with larvae and frass inside.
- Entry holes in fruit with frass, internal tunnelling and rot.
- Green larvae with pale longitudinal stripes; rapid feeding on tender growth.
- Damaged shoot tips and scarred, unmarketable fruit.
Life cycle & spread
Moths lay eggs on foliage and fruit; larvae feed on leaves then bore into fruit/stems; multiple overlapping generations occur in warm cucurbit-growing seasons.
Conditions that favour it
Warm conditions and continuous cucurbit cropping sustain pressure; dense canopies shelter larvae.
Damage and how it spreads
Leaf webbing reduces photosynthesis; fruit boring causes direct cullage and rot entry, the main economic loss in cucurbits.
Monitoring & scouting
Scout for webbed leaves and early larvae; check developing fruit for entries; act on foliar-stage larvae before fruit boring.
How to control it
- Target young larvae on foliage before they enter fruit;
- ensure coverage of sheltered, webbed growth;
- sanitation of infested fruit.
Recommended Vegalab solution: Larva Control
Larva Control — natural broad-spectrum larvicide (oxymatrine) applied at early-instar stage to foliage and developing fruit zones, before larvae bore into the fruit.
| Role | Product | Use |
|---|---|---|
| Primary control | Larva Control |
Preventing it next season
Early scouting, prompt treatment of foliar-stage larvae, canopy management, and sanitation of infested fruit.
Claims and product availability vary by jurisdiction. Always read and follow the product label.