Relationships among male Coleophora deauratella (Lepidoptera: Coleophoridae) pheromone‐baited trap capture, larval abundance, damage and flight phenology

Abstract

1 The red clover casebearer Coleophora deauratella Leinig and Zeller is an invasive pest of red clover (Trifolium pratense L.) grown for seed production in Canada. Drastic yield losses (80-99.5%) have been reported in several growing regions over the last 30 years as a result of larval feeding damage.2 Field trials conducted in red clover seed production fields in Alberta, Canada, during the summers of 2010-2012 tested the efficacy of pheromone-baited traps to predict population density and assess male flight phenology of C. deauratella. 3 Male moth pheromone-trap capture was positively related to larval abundance and proportion seed damage at both moderate and high population densities. 4 Phenological models based on degree days (DD 11.7 ) were better at describing median (50%) male flight compared with ordinal date models. Median C. deauratella male flight occurs at 258.39 DD 11.7 , starting from 1 January each year in the Peace River region of Alberta. 5 The results obtained in the present study demonstrate that pheromone-baited traps can be used to detect the spread of this invasive species. Future work could incorporate pheromone-based monitoring into assessment for the need and timing of control measures to target this invasive pest.

Pheromones and Other Semiochemicals for Monitoring Rare and Endangered Species

“…In pest management, pheromone-based monitoring is to a great extent focused on indications of abundance in relation to economic injury thresholds. Most of these studies deal with future predictions of abundance and/or damage levels based on host and pest phenology and weather conditions (Anderson et al 2012; Damos and Savopoulou-Soultani 2010; Dömötör et al 2007; Hayes et al 2009; Mori et al 2014). Nevertheless, there are a considerable number of studies that relate trap catches to abiotic conditions, which would constitute a platform for normalizing catches between different occasions (Williams et al 2008).…”

Red clover casebearer moth (Coleophora deauratella) is widespread throughout New Zealand

“…1). This is slightly later than the 258 o C days reported by Mori et al (2014) for the Peace River region of Canada although variation in sampling frequency and interventions undertaken by host growers may account for the discrepancy. This difference corresponds to approximately 2-3 days and is likely to make little difference in terms of implementation of management interventions.…”

“…Adults of these species are similar in appearance to, and difficult to distinguish from, C. deauratella which could lead to misidentification in New Zealand. However, C. deauratella is almost exclusively found on red clover and the pheromone is highly specific (Mori et al 2014), thus providing a mechanism for monitoring. Median moth flight activity occurred at 284 o C days (T b =12), starting 1 July 2017 (Fig.…”

Mating disruption ofColeophora deauratella(Lepidoptera: Coleophoridae) using laminate flakes in red clover seed production fields

“…Coleophora deauratella is univoltine, with adults beginning to emerge in late May or early June . Eggs are laid on the calyx of developing red clover florets, and, upon hatching, larvae enter the floret and feed on the developing ovules .…”

“…7 Coleophora deauratella is univoltine, with adults beginning to emerge in late May or early June. 4,6,8 Eggs are laid on the calyx of developing red clover florets, and, upon hatching, larvae enter the floret and feed on the developing ovules. 4,6 The cryptic internal feeding habits of C. deauratella larvae make populations difficult to control with insecticides, and currently there are no registered products available for use.…”