Assessment of DNA Integrity from Trap-Captured Boll Weevils for Use in Pending Diagnostic Tool

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a major pest of commercial cotton (Gossypium hirsutum) in the Southern US (particularly along the US-Mexico border) and throughout Central and South America. Efforts are underway to develop a PCR-based diagnostic tool that can be used to rapidly and accurately differentiate boll weevils from other closely related weevil species (e. g., thurberia weevils), which are commonly captured in boll weevil pheromone traps.  Under typical field scenarios, weevils collected from traps may be dead, dismembered, and/or exposed to adverse environmental conditions for up to 21 days.  Consequently, the integrity of DNA extracted from these weevil specimens may be low or too fragmented for identification via the PCR-based assay.  In order to enhance the commercial potential and adoption of this diagnostic tool, we documented the degradation of DNA quantity and integrity in weevils and weevil body parts aged in traps over a three-week period.