Assessment of the Sterile Insect Technique to Manage Red Palm Weevil Rhynchophorus ferrugineus in Coconut

The red palm weevil Rhynchophorus ferrugineus Olivier is one of the most destructive internal borers of coconut palms in India, Sri Lanka, Indonesia and the Philippines. Recently, this pest has spread to countries in the Persian Gulf and some areas of the Mediterranean basin where it is a serious menace to date palms. Management of this pest using conventional methods is not effective due to the difficulty of detecting early infestations. Trials were therefore conducted to assess the possibility of eventually including the sterile insect technique (SIT) to target populations at low densities as part of future integrated management of this pest. The steps taken included the adoption of a new mass-rearing method for weevils using coconut petioles, determination of the sterilization dose at 15 Gy, a new relative method for estimating population levels of red palm weevils, and finally field release and recapture studies using pheromone traps. This paper deals with the results of these attempts to develop the SIT for use against the red palm weevil on Poothuruth Island near Dalavapuram Island in Kerala.

KEYWORDS red palm weevil, Rhynchophorus ferrugineus, integrated management, sterile insect technique, coconut palm, date palm, release-recapture studies, Kerala