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A study was conducted to determine whether arrays of pheromone traps could be used to reduce populations of male Agriotes obscurus ( AO) and Agriotes lineatus ( AL) adults in a confined nonfarmed habitat (grassy dyke)., Traps placed 3 m apart in 15 × 2 arrays captured significantly more AL than AO, although the trap catch varied with location for both species and was inversely related to the number of nearby competing traps., Models of beetle movement indicated that a considerable proportion of males ( AL: 18.4-71.8%; AO: 35.0-58.3%) collected in the arrays had moved in from elsewhere and that AL beetles are more active than AO beetles. AL beetles frequently entered AO traps unless both trap types were present in the array, whereas AO rarely entered AL traps., Concurrent catches in pitfall traps placed inside and outside pheromone trapping zones indicated the trap arrays significantly reduced male (but not female) AO and AL beetles inside their respective arrays, that AO traps reduced AL beetles in AO arrays, and that both AL and AO traps could potentially reduce the number of mating pairs in these arrays., The implications of these results in determining the efficacy of this approach as a click beetle management approach are discussed. [ABSTRACT FROM AUTHOR]

The present study was conducted using mark-released populations of male Agriotes obscurus ( AO) and Agriotes lineatus ( AL) adults to simulate the spatial and temporal capture rates of wild beetle populations in dense arrays of pheromone traps in a confined, nonfarmed habitat., Two parallel rows of traps, spaced 3 m apart along corridors of grassy dyke, recaptured 85.6% of AO and 77.8% of AL with arrays of their respective pheromone traps, mostly within the first week of release. In arrays of mixed AO and AL traps, recapture rates were 77.8% and 83.3%, respectively., In arrays with only AO traps, 31.2% of AL males released within the arrays mistakenly entered the AO traps, which declined to only 2.2% when released in arrays with both AO and AL traps. In arrays with only AL traps, only 0.7% of released AO were mistakenly taken in the AL traps, and only 0.3% mistakenly entered AL traps in mixed AO and AL trap arrays., Between 34.4-38.9% of AO and 21.1-25.6% of AL released in areas immediately adjacent to the trapping arrays were caught, mostly in the outermost traps., The implications of these results for determining the efficacy of mass trapping as a click beetle management approach are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Phytoprotection is the property of Society for the Protection of Plants and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

1 The production of new insect pheromones for pest monitoring proceeds at a greater rate than their evaluation, with the consequential possibility of premature introduction. Fundamental to their successful deployment is the determination of a consistent relationship between adult male pheromone trap catches and pest damage. In the present study, adult pheromone traps and larval bait traps were used to examine spatial relationships between two species of Agriotes beetle and wireworms at the field scale. 2 The spatial distributions of adult male Agriotes lineatus and Agriotes obscurus in two fields were determined and compared with the distribution of their larvae. Data were assembled as spatially referenced trap counts, and analysed for evidence of aggregation and clustering using Spatial Analysis by Distance IndicEs (SADIE) methodology. Spatial stabilities of adult populations between sampling dates were tested using association tests. Spatial and quantitative linkages between adult and larval trap catches were also tested. Moreover, a new way of adapting SADIE methodologies is presented for situations where two datasets within an area do not share the same sampling points. 3 There was no significant difference in variance : mean relationships for the two species but there were differences in their spatial distributions, and this is a definitive example of the general argument stating that it is important to consider spatial as well as count data in ecological studies. The spatial distribution of A. lineatus varied between sampling occasions at both sites whereas A. obscurus had consistently significant SADIE indices over time at one site, and adult catches could also be linked to larval distributions and counts. It is proposed that observed differences between the two species can be explained by interference between traps and dissimilar movement rates. There was some evidence of an edge effect at the field boundaries. 4 The distance between pheromone traps is related to the time that elapses before adjacent traps interfere with trap captures and this limits the detection of statistically significant spatial patterns. It is shown that the current practice of adding trap counts for different Agriotes species and treating them as numerically equivalent is insufficiently robust to be recommended at this stage. 5 The implications for the use of sex pheromone traps in wireworm pest management are considered. It is concluded that pheromone traps, as currently used, will not reliably indicate where wireworms occur in a field, and that the complexity of interpreting adult male trap counts limits quantitative predictions of population size. [ABSTRACT FROM AUTHOR]

Copyright of Phytoprotection is the property of Society for the Protection of Plants and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The influence of a specially constructed insect exclusion fence on the number of cabbage maggot flies, Delia rndic7nn (L.), and tiger flies CoPno.sin tinr-ian (F.) (a predator of cabbage maggot flies) entering large plots of radish was determined Plots with or without the exclusion fence or with an exclusion fence surrounded by a trap crop ofradish were evaluated in a single growing season in 1995. Overall during the growing season, the mean cabbage fly catch per trap in the completely fenced plots was 90% fewer than in the unfenced control plots. Fewer cabbage flies were caught inside the completely fenced plots than inside the fence surrounded by a trap crop, suggesting that trap crops do not ultimately impede the movement of cabbage flies into fenced enclosures. The general pattern of trap catch of tiger flies in the various treatments was similar to that observed for cabbage flies. During the heaviest infestation of cabbage maggot flies, infestation was highest in the control plots (84.5%), followed by the fence +trap crop plots with 39.8% infested radishes, and the completely fenced plots with 34.7% infestation. The potential of exclusion fences for use in pest management programs for Braccica crops is discussed. [ABSTRACT FROM AUTHOR]

Larvae of two species of click beetle, Agriotes obscurus and Agriotes lineatus, are important pests of vegetable and field crops in both Europe and North America. Both species have been long and extensively studied, but to date little is known regarding the maturation and egg development of female beetles relative to their swarming periods. This knowledge is important for developing wireworm management tactics that target female beetles, as these would ideally eliminate the beetles before they oviposit. This paper is an attempt to address this knowledge gap. We dissected 2,450 female A. obscurus and 477 female A. lineatus collected in southwestern British Columbia in 2015-2020, and describe how their abdominal lipid content and number of mature eggs change during their swarming period. Based on the presence of mature and immature eggs, active ovarioles, and lipid content, we propose 6 consecutive beetle maturity stages. Beetles collected early in the season have high lipid content and no eggs. Over time, immature, then mature eggs appear and the lipid content decreases dramatically. Ovarioles are generally active throughout the swarming period, even when lipids are no longer present, suggesting that for these species egg laying may continue until the end of the season, and that fecundity depends both on a beetle's original lipid content at emergence, and subsequent diet., (© His Majesty the King in Right of Canada 2024. Reproduced with the permission of the Minister of Natural Resources Canada.)

Populations of various economic species of wireworms are increasing in the key cereal crop production areas of Canada and the United States. To address this problem, seed treatments are under development that both provide crop protection and significantly reduce populations equivalent in effectiveness to the formerly used but now deregistered organochlorine lindane. Herein, we evaluated isocycloseram (PLINAZOLIN technology), the first isoxazoline (GABA-gated Chloride Channel Allosteric Modulator) agricultural insecticide, as a seed treatment for the protection of cereal crops from the sugarbeet wireworm, Limonius californicus (Mannerheim). In wheat and barley field trials conducted over 4 years under extreme wireworm pressure, isocycloseram applied as a seed treatment at 5.0-7.5 g AI/100 kg seed was as effective as or more effective than the current industry standard thiamethoxam at 20.0 g AI/100 kg seed in protecting crop stand and yield. Isocycloseram also reduced neonate wireworms (produced from eggs during the growing season) and resident wireworms (in the field at the time of planting) to levels expected from the formerly used seed treatment lindane., (© His Majesty the King in Right of Canada 2024. Reproduced with the permission of the Minister of Agriculture and Agri-Food Canada.)