Friday, August 6, 2010

PS 98-75: Role of food and Kairomone in trapping of adult weevils of Red Palm Weevil, Rhynchophorus ferrugineus in date palm orchards

P.S.P.V. Vidyasagar and Saleh Aldosari. KING SAUD UNIVERSITY


The Red Palm Weevil, Rhynchophorus ferrugineus Olivier is a serious pest of date palm in Saudi Arabia for the past two decades causing heavy economic losses.  One of the methods advocated for the control of R. ferrugineus is the mass trapping with pheromone traps.  However, there is no uniform method of trapping as the efficacy of pheromone trapping depends on the type of food bait as well as kairomone.   Hence, a replicated field trial was conducted to test the effect of various food baits and kairomone combinations on the trapping of adult Red Palm Weevils, in date palm orchards of Al Kharj, Saudi Arabia.  Aggregation pheromone Ferrolure+ baited traps with five different combinations of food baits and ethyl acetate, a known kairomone were tested in the field.  The treatments were pheromone lure + date fruits, pheromone lure + date stem pieces, pheromone lure + sugarcane + ethyl acetate, pheromone lure + date fruits + ethyl acetate, and pheromone lure + date stem + ethyl acetate.  The Saudi bucket trap with a wrapping was used for this experiment with water and pesticide added to kill the attracted insects.  The traps were serviced at weekly intervals and the trial was continued for a period of five weeks.  


The data on the adult weevils captured in various treatments are analyzed by standard statistical methods.   From the studies it has been found that treatment with date fruits and ethyl acetate has given the best results with an average weekly capture of 3.38 weevils per trap over the experimental period.   When date fruits alone were used as food baits without kairomone the weevils trapped weekly was reduced to only 2.46 per trap.  The lowest number of weevils of 1.66 per trap was recorded in the treatment with date stem pieces.  From this experiment it is concluded that use of date fruits as food bait along with ethyl acetate is the best combination for mass pheromone trapping of Red Palm Weevils.