English abstract
The date palm fruit stalk borer, Oryctes elegans, is widely distributed in Saudi Arabia. Undetected and untreated infestations by this pest result in severe losses. Light trap studies to investigate seasonal population fluctuations of O. elegans were conducted in Al-Rajhi Endowment date palm plantation in Al-Qassim, Saudi Arabia, by installing three modified Robinson mercury-vapor light traps in 3 different equidistant sites. The investigation revealed that light trapping is an effective tool for the monitoring and forecasting of O. elegans infestations. The highest activity of O. elegans was witnessed from April to July, during which period 65% of adults captures were made. Peak monthly activity was observed during June, when 19.4 % and 22.2% of the catches were made during 2003 and 2004, respectively. No beetle activity was observed during January and February. The highest number of beetles (56.6% of the population) was recovered in the site with relatively old and tall palms (more than 18 years old and averaging 7.5m in height). The site with shorter and younger palms received 29.6% of the beetles, whereas the uncultivated site had the lowest number of beetles (13.8% of total).
