Population dynamics of the tomato leaf miner Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Tunisia natural conditions

Abstract

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a key pest of tomato crops in Tunisia causing heavy losses to its production. The population dynamics of this pest was surveyed during spring-summer tomato growing season in Zaghouan and Nabeul provinces between 2014 and 2016. T. absoluta was monitored using two sex pheromone water traps. Tomato leaves were harvested and inspected weekly in order to determine the number of generation accomplish by each alive instar (eggs, larvae and pupae). Mines with and without larvae are also counted. Results showed that this pest was able to achieve 4-5 flight peaks. Three generations of eggs and larvae were recorded with a significant preference to laid eggs in the underside of leaves. High correlations were found between traps catches, eggs laid, active and total mines. Obtained data may help Tunisian farmers to detect early infestations, therefore to establish and to apply efficient control methods.