Molecular identification of Agriotes larvae allows examining species-specific traits

Click beetle larvae within the genus Agriotes (Coleoptera: Elateridae), commonly known as wireworms, are abundant ground-dwelling herbivores which can inflict considerable damage to field crops. In Central Europe up to 20 species, which are likely to differ in their distribution, ecology and pest status, occur in arable land. However, the identification of these larvae, based on morphological characters, is difficult or sometimes even impossible. Here, we present a DNA-based approach to identify 17 Agriotes species typically found in Central Europe. Diagnostic sequence information was generated and submitted to GenBank/BOLD. Based on these barcodes, the respective Agriotes species can be identified. Moreover, multiplex PCR assays were developed, allowing the rapid identification of the nine most abundant species within a single-step reaction. The molecular identification system was evaluated by screening over 1,300 field-collected Agriotes larvae from 80+ field sites in Austria. Over 85 % of the larvae could be identified by multiplex PCR, allowing the assignment of these specimens to six different Agriotes species (Agriotes brevis, A. litigiosus, A. obscurus, A. sputator, A. ustulatus and A. lineatus/proximus). These data, in combination with abiotic field data, is currently being analyzed to examine how soil and climatic parameters may affect the distribution of Agriotes species in Austria.