Effect of density and color on the trapping efficiency of the Kairo-pheromonal trap for date palm fruit stalk borer, Oryctes elegans Prell (Coleoptera: Scarabaeidae)

The date palm fruit stalk borer, Oryctes elegans Prell (Coleoptera: Scarabaeidae), is one of the most destructive endemic pests of palm groves in Iran. Recently, there has been a trend toward using kairomone or pheromone trapping as a preferred method of controlling this borer to preserve and protect the environment. The current field study examined the effects of trap density (6 or 10 traps/ha) and trap color (black, white, red, and yellow) on the attraction of adults of O. elegans to a Kairo-pheromonal diffuser (Ferrolure manufactured by Econex Ltd, Spain) in four infested date palm groves in Shalheh-ye Emam Hasan, Abadan, southwestern Iran. Among the test density, 6 traps/ha could accurately detect the presence of adults of O. elegans in the field and help monitor O. elegans. However, 10 traps/ha caught significantly more adults than 6 traps/ha. At both densities, trap colors significantly affected adults' mobility and dispersal to traps. The black traps captured the most significant number of adults in the field, followed by the yellow, red, and white traps. In addition, there was no significant difference between the total numbers of adults captured in traps with different colors during four different times of sampling. As a result, the black traps with 10 traps/ha yield better results at capturing in the field. Our results provide the basic information for developing a safe mass trapping system to control O. elegans.