author(s)
Adja Nahoulé Armand, Ouédraogo Yacou, Kouakou Malanno, Fondio Lassina, Akamou Fataye and Danho Mathias

abstract
Tomato (Solanum lycopersicum L.) is an important vegetable crop for income and nutrition of smallholder farmers in sub-Saharan Africa. Its infestation by the leaf miner Tuta absoluta (Meyrik) results in a considerable economic loss. This pest was recorded for the first time in the centre of Ivory Coast during 2016. Therefore, the current study aims to monitor the population of Tuta absoluta adults and determine the impact of the larvae on tomato plants. Treated and untreated plots arranged in complete random blocks with 5 treatments (4 insecticides and one control) and 3 replicates were installed at Djébonoua (7°30'N: 5°5'W), in the centre of Ivory Coast. Delta trap with pheromone, efficiency for monitoring the male insect was tested during one tomato season in 2017. Direct examination of tomato revealed a fluctuation of the insect larvae and their impact on tomato plants and yield. Data collected were analyzed with Statistica 7.1 at 5%. Monitoring of males catches revealed that the locality has a high risk of infestation (more than 30 males per week). The insecticides Tihan175-O-Teq (Spirotetramate 75g/l and Flubendiamide 100g/l), Viper 46 EC (Acetamiprid 16g/l and Indoxacarb 30g/l), Vertimec 18 EC (Abamectin 18g/l) and K-Optimal (Lambdacyhalothrin 15g/l and Acetamiprid 20g/l) significantly reduced larval populations and their damage on plants and fruits compared to the control. The results showed high efficiency of Tihan (0.4 l/ha) and Viper (1 l/ha), average efficiency of Vertimec (1 l/ha) and low efficiency of K-optimal (1 l/ha). Insecticides control Tuta absoluta larval populations, reduce its damage and improve the yield from 54.85 to 144.65% compared to the control. Tihan and Viper can be recommended at fourteen days and Vertimec at seven days of intervals.