This study was carried out with a view to determine population dynamics of tomato leaf miner [Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)] in tomato growing areas of Bismil and Ergani counties in Diyarbakır province between 2011 and 2012. For monitoring population development of tomato leaf miner one tomato field from each district was determined. According to the size of each field 1 sexual attractive trap for per acre (da) was hanged and studies carried out weekly from early seedlings period to the end of harvesting. Together with this study simultaneously tomato plants and fruits observed weekly by visual method to determine infection rate of pest. According to the results of this study, adult population dynamic in both years reached maximum level in 5 different time points (in July, August, September and October) in Bismil county, while reached maximum level in 3 different time points (in August, September and October) in Ergani county. The most number of T. absoluta adults on traps was determined as 429 adults/ trap in 04 August 2011and 529 adults/ trap in 15 October 2012 in Bismil county, while 251 adults/ trap in 20 October 2011 and 395 adults/ trap in 26 October 2012 in Ergani county. Tomato plants and fruits were highly infected with T. absoluta both years as 100 % in Bismil county, while this level was lower (60-90 % plants, 20-30 % fruits) in Ergani county.

This study was carried out with a view to determine population dynamics of tomato leaf miner [Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)] in tomato growing areas of Bismil and Ergani counties in Diyarbakır province between 2011 and 2012. For monitoring population development of tomato leaf miner one tomato field from each district was determined. According to the size of each field 1 sexual attractive trap for per acre (da) was hanged and studies carried out weekly from early seedlings period to the end of harvesting. Together with this study simultaneously tomato plants and fruits observed weekly by visual method to determine infection rate of pest. According to the results of this study, adult population dynamic in both years reached maximum level in 5 different time points (in July, August, September and October) in Bismil county, while reached maximum level in 3 different time points (in August, September and October) in Ergani county. The most number of T. absoluta adults on traps was determined as 429 adults/ trap in 04 August 2011and 529 adults/ trap in 15 October 2012 in Bismil county, while 251 adults/ trap in 20 October 2011 and 395 adults/ trap in 26 October 2012 in Ergani county. Tomato plants and fruits were highly infected with T. absoluta both years as 100 % in Bismil county, while this level was lower (60-90 % plants, 20-30 % fruits) in Ergani county.