Leaf miner Tuta absoluta (Meyrick)
Identification :
- absoluta is a microlepidoptera of the Gelechiidae family.
- The eggs are tiny, measuring less than a millimeter, cylindrical in shape, and cream to yellowish in color.
- The larvae are a few millimeters long.
- The larvae are initially creamy, then greenish to pinkish.
- The pupa stage takes place either inside the galleries dug by the larvae, or on the surface of the host, or on the ground.
- The adults are butterflies measuring 5-7mm in length and about 10mm in wingspan.
- They have a silvery gray to brown tint with black spots on the forewings.
Biology :
- absoluta goes through 4 stages of development: egg, larva, pupa and adult.
- The duration of its biological cycle varies according to the temperature (for example: 24 days at 27 ° C).
- The number of generations can be up to 12.
- Overwintering occurs in the form of eggs, pupae or adults.
- The main host of absoluta eis tomato, but it can also parasitize various other cultivated and wild Solanaceae species.
- The eggs are laid with 40 to 250 eggs, often located on the underside of the leaves or at the level of young tender stems and the sepals of young fruits.
- Hatching is 4 to 6 days after laying.
- Pupation lasts 10 to 12 days.
- The approximate lifespan of adults is 6-7 days for males and 10-15 days for females.
Symptoms :
- The larvae of absolutadig mines and galleries on the aerial organs of the tomato.
- Only the tissues of the mesophyll are affected, the epidermis remains intact.
- Heavily parasitized leaves can completely necrode.
- Green fruits, like ripe fruits, are more or less strewn with galleries and exit holes.
- Galleries may appear on young stems, disrupting plant development.
- Black feces are visible on the affected organs.
Control :
- Prophylactic measures by removal and incineration of parasitized leaves, stems and fruits. Also by regular stripping of parasitized plants and removal of leaves
- Elimination of weeds likely to harbor the pest.
- Installation of pheromone traps for mass monitoring or trapping.
- Chemical control using AVAUNT 150EC at a dose of 25 ml / hl.
- Chemical control using CORAGENat a dose of 15 ml / hl.
- Chemical control using BENEVIAat a dose of 60 ml / hl.
- Chemical control using VERIMARKat a rate of 375 ml / ha.
