Résumé:
Since its introduction in the Mediterranean basin in 2006, Tuta absoluta Meyrick (Lepidoptera ; Gelechiidae) has become the first pest of tomato (Lycopercicon esculentum Mill.). Since its record in 2008 in Algeria, chemical control has become the only solution for farmers. As part of integrated pest management several methods need to be combined.The culture was planted in a greenhouse unheated at the experimental farm of the University of Mostaganem in Mazagran in order to assess the risk of attacks and infestations. The tomato cop did not receive any insecticide or release of entomphageous.To estimate the importance of larval populations inside the greenhouse we sampling nine leaflets per plant on 36 plants spread across all ranks. We installed a three sex pheromone trap and counted the number of catches of males once a week. The trial showed a delay in the leafminer infestation compared to previous years because of the climate infestation began in March with a level of 5% of active mines. It was noted tow generation during the trial period the maximum threshold of infestation was recorded during the third week in april .With 5.64larvae/plant and 377 males caught. This study allows us to better understand the behavior of the leaf miner and the usefulness of prophylaxis to reduce rhe risk of infection
