Sugarcane stalk borer

Diatraea saccharalis

1. Identification

• Common name: Sugarcane stalk borer
• Scientific name: Diatraea saccharalis Fabricius
• Order: Lepidoptera
• Family: Crambidae

2. Description of the pest

• Adults: Medium-sized moths (≈ 20–28 mm wingspan); straw-yellow to brownish wings; slender body.
• Larvae: Cream to yellowish caterpillars, with faint longitudinal lines; brown head; up to 25–30 mm long; develop inside the stalk.
• Eggs: Laid in masses on the leaves, usually on the underside.

3. Main hosts

• Sugarcane.
• Maize.
• Sorghum.
• Other cultivated and wild grasses of lesser importance.

4. Symptoms and damage

• Perforations in young leaves, forming “windowing”.
• Perforation of the stalk, with internal galleries that reduce sap transport.
• Stalk breakage and lodging in severe attacks.
• Reduction in sucrose content and in productivity.
• Facilitated entry of secondary pathogens.

5. Biological cycle

• Overwinters as a larva inside the stalk or in crop residues.
• Adults emerge in spring and summer.
• Females lay eggs in masses on the leaves.
• Caterpillars quickly bore into the stalk, where they complete their development.
• Pupation inside the stalk or in the soil.
• 2 to 4 generations per year, depending on climatic conditions.

6. Monitoring

• Observation of “windowing” in young leaves.
• Opening of stalks to detect galleries and caterpillars.
• Monitoring of adults with light traps or pheromones.
• Historical record of the holding for risk forecasting.

7. Management measures

• Cultural: Destruction of crop residues; crop rotation; choice of less susceptible varieties; staggered sowing.
• Biological: Release of parasitoids (e.g.: Cotesia flavipes); conservation of natural enemies.
• Integrated protection: Intervention based on monitoring; application of selective methods compatible with beneficials; avoid late treatments due to the protection the stalk provides to the caterpillars.

Bibliographic references

• CABI Invasive Species Compendium – Diatraea saccharalis.
• EPPO Global Database – Diatraea saccharalis.
• White, W. H. et al. (2008). Biology and management of sugarcane borers.
• Pashley, D. P. (1990). Host-associated genetic differentiation in Diatraea.