Dr Alejandro Trujillo-González1, Dr David N. Thuo, Dr Uday Divi2, Dr Kate Sparks2, Dr Thomas Wallenius2, Professor Dianne Gleeson1
1University Of Canberra, Canberra, Australia, 2Department of Agriculture, Water, and the Environment, Canberra, Australia
Khapra beetle, Trogoderma granarium Everts, 1898, is a serious pest of stored grain products globally. Environmental DNA (eDNA)-based methods offer the potential for non-invasive, sensitive detection tools used to inform biosecurity officers on the presence of high-risk pests. This study tested laboratory and portable molecular technologies to detect khapra beetle environmental DNA extracted from dust samples collected during biosecurity responses to khapra beetle incursions. DNA amplification was tested using Real time PCR and LAMP-based assays. We successfully collected, extracted, and amplified khapra beetle eDNA from dust samples collected during biosecurity responses using field and lab-based methods. DNA yield achieved with field and lab-based extraction kits ranged between 0-16.79 and 0.93-9.45 ng/µL, respectively, from biosecurity responses. TaqMan assays successfully amplified T. granarium eDNA, while LAMP failed to amplify eDNA. Field testing showed a high incidence of false positive detections and cross-contamination of samples during the two separate biosecurity responses (Tuggeranong (16/42) = 38% and Fyshwick (6/6) =100%), mostly attributed to the use of contaminated vacuum cleaners. We discuss suitable methods to minimize sample cross-contamination, the potential of portable molecular technologies as viable tools for biosecurity officers in Australia, and the suitability of eDNA-based molecular detection methods to complement global trade biosecurity for one of the most invasive and important grain pests worldwide.
Biography:
Alejandro is a Senior Research Fellow at the University of Canberra who specializes on eDNA and biosecurity applications