Importance of date fruit in red palm weevil, Rhynchophorus ferrugineus olivier (Coleoptera: Curculionidae) aggregation pheromone traps

Experiments were conducted in four date palm plantations at Al-Rahbba from May 2004 to April 2005. Twelve pheromone traps were set in each plantation, to investigate the effect of adding dates as a bait, on the capture of the red palm weevil (RPW), Rhynchophorus ferrugineus Olivier (Curculionidae: Coleoptera). The traps contained the aggregation pheromone 4-Methyl-5-Nonanol 90% + 4-Methyl-5-Nonanon 10% and 350g of dates. The catch was compared to the catch in traps containing either the pheromone alone or dates alone. The pheromone lure in each trap was changed every three weeks, while the water and dates were changed every 2 weeks. The number of RPW captured in the 16 traps was 1752, 181 and 54 insects for the three treatments, respectively. There were significant differences between the three treatments. The first treatment catch value was 10 and 32 times the second and third treatment value, respectively. The second treatment catch value was more than three times the third treatment catch value. The experiment also showed that adult RPW were present throughout the year, and the number of females was higher than the number of males. The numbers of captured insects were 420, 452, 542 and 573 adults at the four plantations, respectively. The reason behind the variation in numbers could be explained by a variety of factors such as farm practices, differences in tree age and source, and farmer knowledge.