Life Cycle of Bombyx mori

Life Cycle of Bombyx mori

• Overview

  • Bombyx mori, commonly known as the silkworm, undergoes a complete metamorphosis with four life stages: egg, larva, pupa, and adult.

• Egg Stage

  • Duration: Approximately 10 days.
  • Description:
    • The eggs are small, spherical, and typically white or light yellow.
    • Laid in clusters by adult female moths.
    • Incubation period influenced by temperature and humidity.
  • Hatching:
    • Eggs hatch into larvae (caterpillars) when conditions are favorable.

• Larval Stage

  • Duration: 4 to 6 weeks, with 5 larval instars.
  • Description:
    • Newly hatched larvae are very small and size increases significantly during growth.
    • Key characteristic: voracious appetite, feeding primarily on mulberry leaves.
    • They undergo several molts (instars) where they shed their skin to accommodate growth.
  • Behavior:
    • Active feeding and growth phase, able to consume large amounts of leaves.
    • Once growth is complete, they prepare for pupation.

• Pupal Stage

  • Duration: Approximately 2 to 3 weeks.
  • Description:
    • The larva spins a protective silk cocoon, which can weigh about 10 to 15 grams.
    • Inside the cocoon, the larva transforms into a pupa.
    • Metamorphosis occurs as the pupa develops into an adult moth.
  • Cocoon Characteristics:
    • Made of continuous silk thread; vital for silk production.
    • The cocoon provides protection during the metamorphosis process.

• Completion of Life Cycle

  • After the pupal stage, the adult moth emerges from the cocoon.
  • The entire life cycle from egg to adult may take around 6 to 8 weeks under optimal conditions.

Bombyx mori Life Cycle

• Bombyx mori undergoes complete metamorphosis with four distinct stages: egg, larva, pupa, and adult.
• The egg stage lasts approximately 10 days and involves the incubation period.
• Eggs are small, spherical, and white or light yellow, laid in clusters by female moths.
• Hatching depends on favorable temperature and humidity conditions.
• The larval stage lasts 4 to 6 weeks, with five larval instars, during which the larva grows significantly.
• Newly hatched larvae are small but grow rapidly through voracious feeding on mulberry leaves.
• Larvae molt several times (instars) to accommodate their increasing size.
• The pupal stage lasts approximately 2 to 3 weeks, during which the larva transforms into a pupa within a silk cocoon.
• The larva spins a cocoon of continuous silk thread for protection and metamorphosis.
• The cocoon weighs approximately 10 to 15 grams.
• The adult moth emerges from the cocoon after the pupal stage, completing the life cycle.
• The complete life cycle, from egg to adult, takes approximately 6 to 8 weeks under optimal conditions.