Efficacy of different density of pheromone traps on an attack of lined click beetles (Agriotes lineatus L.)

Abstract

In 2004 lined click beetles (Agriotes lineatus L.) were swarming in the vicinity of Ljubljana from the 20th to the 36th week (May 10 -August 30) with a catch peak in the 25th week (on June 14 and 17), when 876 lined click beetles were captured by a single pheromone trap (type Yatlor) within a single week. In 2005 they were swarming from the 17th to the 34th week (April 28 - August 25) with a catch peak in the 21st and 22nd week (on May 23, 26 and 30, and June 2) and in the 26th week (on June 27 and 30), when 569 lined click beetles were captured by a bait trap on June 27. An increase in their activity was influenced by higher temperatures of air and soil, while precipitation did not seem to have a significant effect. In order to reduce their population levels, mass trapping was used. Results show that most specimens were captured in a field trial with eight pheromone traps (2940 specimens in total in 2004, and 1444 specimens in total in 2005), which was followed by a field trial with two traps (1268 specimens in total in 2004, and 752 specimens in 2005) and by a field trial with four traps (1120 specimens in 2004, and 664 specimens in 2005). The lowest number of lined click beetles were caught by a single bait trap (505 specimens in 2004, and 178 specimens in 2005). A statistically significant difference in the number of Agriotes lineatus captured was found in results obtained in 2004 and in 2005 in the field trial with eight pheromone traps