Study of the Evaluation of Damage Caused By Tuta Absoluta (Meyrick) (Lepidoptera: Gelichidae) on Tomato Field in Morocco

Tomato crops in the field, suffering the attacks of a new miner: Tuta absoluta (Meyrick) that caused significant losses in production. The insect may cause losses on tomatoes up to 80 to 100%. The larva is the damaging stage of the tomato leafminer. The first attack is observed on the apical parts of the plant, namely leaves and seedlings. This insect can also attack young transplants and even nursery seedlings. The attacks are manifested by the appearance on the leaves whitish galleries (only the epidermis of the leaf remains, the parenchyma is consumed by the larvae) each containing a caterpillar and its droppings. Over time, the galleries become necrotic and turn brown. The caterpillars attack the green fruits like ripe fruit. Tomatoes are necrosis on the calyx or exit holes on their surface. The fruits are then unmarketable and unfit for consumption.

The study and evaluation of damage caused by Tuta absoluta on tomato leaves in the field have shown the great danger of this insect for growing tomatoes. Indeed, in the absence of any intervention, in the conditions of the Moroccan Gharb fields, a couple of the pest Tuta absoluta comes to destroy all the leaves of a tomato field with an area of 500 m2 sixty-nine (69) days.

Keywords: tomato crop, field, tomato leafminer (Tuta absoluta), Gharb Morocco