PCR-based species identification ofAgrioteslarvae

Abstract

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 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 impossible. This hampers progress towards controlling these pests. Here, we present a polymerase chain reaction (PCR)-based approach to identify, for the first time, 17 Agriotes species typically found in Central Europe. Diagnostic sequence information was generated and submitted to GenBank, allowing the identification of these species via DNA barcoding. Moreover, multiplex PCR assays were developed to identify the nine most abundant species rapidly within a single-step reaction: Agriotes brevis, A. litigiosus, A. obscurus, A. rufipalpis, A. sordidus, A. sputator, A. ustulatus, A. lineatus and A. proximus. The latter two species remain molecularly indistinguishable, questioning their species status. The multiplex PCR assays proved to be highly specific against non-agrioted elaterid beetles and other non-target soil invertebrates. By testing the molecular identification system with over 900 field-collected larvae, our protocol proved to be a reliable, cheap and quick method to routinely identify Central European Agriotes species.

Agriotes proximus and A. lineatus (Coleoptera: Elateridae): a comparative study on the pheromone composition and cytochrome c oxidase subunit I gene sequence

“…air entrainments, and data on their electrophysiological and behavioural activities (Tóth et al 2008), as well as the preliminary molecular comparison of the two species in the present study may suggest the taxa to which the two described morphological forms belong, represent a stage of species diversification, or may just be geographical populations or races of the same species. This may be supported by Staudacher et al (2011) who also found high similarity between the two species based on the analysis of a region of the COI gene different from that investigated in this study. To test this hypothesis, additional studies concerning the similarities/differences in other regions of the genom (e.g.…”

Control methods and monitoring of Agriotes wireworms (Coleoptera: Elateridae)

“…Agriotes proximus, also classified as a destructive species, might just be a synonym for A. lineatus. According to Staudacher et al (2011a), PCR analyses showed a high similarity between A. lineatus and A. proximus. Additionally, both species were found to be attracted to the same pheromone composition (Tóth et al 2008, Vuts et al 2012.…”

“…1/2013 Furlan 1998, Furlan 2004, ecology (Staudacher et al 2011a, Brunner et al 2011, crop preferences (Furlan 2011, Ritter unpublished data) and damage level (Furlan 2011). Furlan (2005b) divided Agriotes species into two groups, according to their life cycle: (1) species with adults overwintering, and (2) species with adults which do not overwinter.…”

“…However, the main difficulty of a microscopic determination, are individually varying characteristics which are often not perfectly preserved. Two molecular identification assessments, published by Staudacher et al (2011a) and Benefer et al (2012), provide a reliable method to distinguish between the most destructive Agriotes species. However, this takes time and effort to process.…”

Understanding the ecology of wireworms and improving their control: a special issue

“…New monitoring approaches, including the assessment of adult populations using pheromones, are thus needed. The identification of wireworms to species level is a prerequisite to develop successful control measures, but it is challenging and represents an area where new techniques are needed to allow for reliable and rapid taxonomic assignment of larvae (Staudacher et al 2011). The search for effective biological control agents such as entomopathogenic fungi is another important aspect to develop new measures for wireworm regulation.…”