Tobacco stem borer

Scrobipalpa aptatella

Overview:

Type of Pest: Scrobipalpa aptatella, commonly known as the Potato Tuber Moth, is a moth species that poses a threat to potato crops and other related plants.

Physical Characteristics:

  • Adults: Small, brownish-gray moths with a wingspan of about 10 to 14 mm.
  • Larvae: Larvae are caterpillar-like, cream-colored with a dark head.

Life Cycle:

  • Egg Stage: Eggs are laid on plant surfaces, including leaves and stems.
  • Larval Stage: Larvae hatch and bore into potato tubers or other host plants.
  • Pupal Stage: Pupation occurs within the infested tubers or in the soil.
  • Adult Stage: Fully developed moths emerge, and the cycle repeats.

Identification of Crop Infestation:

  • Tuber Damage: Larvae tunnel into potato tubers, causing damage and rendering tubers unmarketable.
  • Leaf Damage: Feeding on leaves results in irregular holes and damage.
  • Frass: Presence of insect excrement (frass) near feeding sites.

Management Strategies:

  1. Cultural Practices:

    • Crop Rotation: Rotate crops to disrupt the life cycle and reduce pest pressure.
    • Harvest Timing: Harvest potatoes promptly to minimize tuber exposure to moth infestation.

  2. Biological Control:

    • Natural Enemies: Encourage natural enemies such as parasitoid wasps and predatory beetles.
    • Bacillus thuringiensis (Bt): Use Bt formulations specific to lepidopteran larvae.

  3. Chemical Control:

    • Insecticides: Application of insecticides may be necessary, especially during periods of peak moth activity.
    • Systemic Insecticides: Consider systemic insecticides for targeted control.

  4. Phytosanitary Measures:

    • Tuber Inspection: Inspect potato tubers during storage and before distribution for signs of infestation.
    • Quarantine Measures: Implement measures to prevent the spread of infested planting material.

  5. Monitoring:

    • Pheromone Traps: Use pheromone traps to monitor adult moth populations.
    • Field Scouting: Regularly scout fields for signs of moth activity and tuber damage.

Note: The Potato Tuber Moth can cause significant economic losses in potato production. Integrated pest management (IPM) practices that combine cultural, biological, and chemical control methods are essential for effective pest management. Always follow recommended guidelines and consult with local agricultural experts for site-specific recommendations.