Life cycle and identification of Tuta absoluta

Life Cycle

Tuta absoluta has four larval instars, with each stage developing and feeding within mines inside the leaf. The mining occurs between the upper and lower epidermis layers. Some larvae may be present in the fruit and stems of the target crop.

The next stage in the life cycle of T. absoluta is development into pupae, which are typically found in soil and occasionally, on the tomato plant.
Overwintering can occur at any stage in the life cycle of Tuta, i.e. the larval, pupal and adult moth life stages. The larvae of Tuta will not enter diapause unless food is scarce.

 

Identification of the Tomato leaf miner moth

  • Adults are 5-7 mm long and with a wingspan of 8-10 mm.
  • Key identifying characteristics: long, hair-like antennae and silver-grey scales.
  • Adult females lay eggs on host plants and mature female could lay up to 260 eggs before completing life cycle.

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Identification of the Tomato leaf miner eggs

  • The eggs of absoluta are small cylindrical, creamy white to yellow and approximately 0.35 mm long.
  • Egg hatching takes place between 4 to 6 days after egg laying.

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Identification of the Tomato leaf miner larvae

  • The larvae are cream in colour with a characteristic dark stripe on the head.
  • Pupae tend to be brown in colour and around 6 mm in length.

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Life Cycle

Egg

Duration: 7 days

The eggs of T. absoluta tend to be laid on the underside of the leaves of the host plant.

Larvae

Duration: 11 days

After 4 larval instars the larvae will fall to the ground in a silken thread, ready to begin pupation in the soil. The larvae are very unlikely to enter diapause as long as food source is available. Tuta absoluta can overwinter as eggs, pupae and adults.

Pupa

Duration: 5 days

Development of Tuta pupa takes place in the soil and occasionally on plant parts such as the stem.

Adult

Duration: 9 days

Adult moths of Tuta absoluta are relatively small with a body length of ~7mm. The body is brown in colour with darker flecks of colour on each wing.

 

The duration of the T. absoluta life cycle in different environments:

  • 14°C will take approx. 76 days
  • 20°C will take approx. 24 days
  • 27°C will take approx. 24 days