Toxicity and field efficacy of emamectin benzoate (ARETOR) against red palm weevil, by using Syngenta Tree Micro-Injection Technique.
Invasions of the red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier) has become a well-known problem for several palm species in date palm-growing states, including Saudi Arabia. Although several control measures have been implemented in efforts against RPW, yet, no approach has proven consistently effective against this invasive pest. Therefore, further efforts are still needed to develop an effective and efficient control method for RPW management and mitigation. The objectives of the present study were to determine emamectin benzoate (ARETOR) efficacy against RPW larval stages, in the laboratory using a diet incorporation bioassay, along with field tests of the Syngenta Tree Micro-Injection Technique. Our laboratory bioassay showed that the median lethal concentration of emamectin benzoate (ARETOR) was 0.30 μg/mL-1 against wild populations of RPW larvae. In the field studies, emamectin benzoate (ARETOR) showed promising effects on RPW mortality for all stages. We found 100% mortality for both larval and pupal stages for all exposure times, except after 2 months, where 86% mortality was observed for larvae. Thus, we conclude that emamectin benzoate (ARETOR) is an effective biopesticide against RPW. Our results show that it killed RPW all stages, also prevented further damage to the healthy tissues of date palms, in addition, provided protection against RPW spread to other neighboring healthy date palms.