Impact of vitellogenin based dsRNA feeding on reproductive biology of red palm weevil, Rhynchophorus ferrugineus (Olivier), (Coleoptera: Dryophthoridae) under laboratory conditions

Abstract

Objective: Red palm weevil, Rhynchophorus ferrugineus is a crucial pest of date palm, in the Kingdom of Saudi Arabia including several other palm producing countries of the World. The vitellogenin gene play very important role for oocytes development in all oviparous animals. Recently, we have silenced the vitellogenin gene by injecting the RfVg-based dsRNA and proved that RNAi technology can be used to manage red palm weevil. The main challenge in RNAi-based plant protection methods is selecting a suitable tactic for successfully delivering the dsRNA. Methods: In the present study, 9-10th instar red palm weevil larvae were provided with Vg-based dsRNA in diet and as drops to determine its effects on red palm weevil reproductive traits, such as pre-oviposition period, fecundity, oviposition period, post oviposition period, eggs size, and female and male life span. Results: Results demonstrated that the RfVg gene function was successfully suppressed using Vg-based RNAi. When applied via drops, resulting in a significant decline in red palm weevil eggs hatchability and Vg expression measured by quantitative real time Polymerase chain reaction. However, when applied via diet, Vg-based dsRNA did not show any significant effect on fecundity, oviposition period, post oviposition period, eggs size, and female and male life span. Conclusions: Based on present overall results and our previous findings, along with the documented information, we can conclude that Vg-based RNAi has a high potential for use as a target specific and eco-friendly technique for the sustainable control of this crucial pest.

Keywords

• RNAi
• Oviparous
• Date palm
• Vitellin
• Gene function
• Saudi Arabia