Insecticide Injection For Weevil Control

About 2.2 million tons of dates are produced in the Gulf region of the Middle East. The red palm weevil is a lethal pest of date palm trees –infested palms often die if not detected early and treated with insecticides. The thumb-sized grubs make so much noise eating that if you stand next to an infested tree, you can actually hear them munching their way through the trunk. Management depends on detecting the weevils in traps and injecting a chemical insecticide into the tree. An aggressive trapping and treatment program in Saudi Arabia has greatly reduced the problem.

“Red palm weevil is a native to south and southeast Asia where it is a notorious pest of coconut palms… Subsequent movement of infested plant material introduced this pest into Saudi Arabia in 1987 where it presented a significant threat to this country’s multi-million dollar date industry.

R. ferrugineus induced palm mortality results from internal feeding by weevil larvae and to a lesser extent, adults… This internal feeding, when severe enough, can weaken the trunk causing the collapse and premature death of P. dactylifera.

R. ferrugineus infestations of date palms in Al Ghowaybah increased significantly in 2009. In response to this outbreak, the Directorate of Agriculture in Al Ahsaa increased areawide treatments against R. ferrugineus on three different fronts: (1) the number of pheromone traps throughout the 1140 ha management area was increased 11 fold… (2) the number of date palms treated with pesticides increased 48 fold from 11,000 palms in 2008 to 531,590 in 2009, and (3) eradication of R. ferrugineus infested palms increased three fold from 2008 (1026 infested palms removed and destroyed) to 2009 (3097 date palms eradicated). These enhanced management practices in Al Ghowaybah had a rapid effect on R. ferrungineus populations as determined by the average number of weevils captured monthly in pheromone bucket traps and the monthly percentage of traps with weevils. In 2009, prior to the Oct. increase in pheromone trap numbers, ~5 adult weevils were captured per trap per week, compared to an average of 1.6 weevils per trap for 2012, which represents an ~68% decrease in the average number of weevils captured per trap.

It is likely that intensive R. ferrugineus management practices in Al Ghowaybah will need to be sustained at this current high level as long as new plantations are being developed and the majority of dates are <20 yr old, an age susceptible to attack.”

Authors: Hoddle, M. S., et al.
Affiliation: University of California
Title: Assessing the impact of areawide pheromone trapping, pesticide applications, and eradication of infested date palms for Rhynchophorus ferrugineus (Coleoptera: Curculionidae) management in Al Ghowaybah, Saudi Arabia.
Source: Crop Protection. 2013. 53:152-160.