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Joseph S. Elkinton - One of the best experts on this subject based on the ideXlab platform.
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Successful biological control of winter moth, Operophtera brumata, in the northeastern United States.
Ecological applications : a publication of the Ecological Society of America, 2021Co-Authors: Joseph S. Elkinton, George H. Boettner, Hannah J. BroadleyAbstract:Winter moth, Operophtera brumata, native to Europe, invaded the northeastern United States in the late 1990s, where it caused widespread defoliation of forests and shade trees ranging from 2,266 to 36,360 ha per year between 2003 and 2015 in Massachusetts. In 2005, we initiated a biological control effort based on the specialist tachinid parasitoid Cyzenis albicans, which had previously been introduced along with the generalist ichneumonid parasitoid Agrypon flaveolatum to control winter moth in Nova Scotia in the 1950s and British Columbia in the 1970s. Due to concerns of possible non-target impacts by A. flaveolatum, we focused entirely on the specialist C. albicans. Each year for 14 years, we collected several thousand individuals of C. albicans from British Columbia and released them in widely spaced sites in the northeastern United States. As of 2020, we had established C. albicans at 41 of 44 sites from coastal Maine to southeastern Connecticut. By 2016 winter moth densities (pupae/m2 ) had declined from 100-500 pupae/m2 to 0-10 pupae/m2 at six release sites at least 10 km apart and this was coincident with the onset of 10-40% parasitism. At one site in Wellesley, Massachusetts, the decline occurred in 2012 and winter moth densities have remained low for seven subsequent years. Defoliation in Massachusetts has been reduced to undetectable levels since 2016. DNA sequencing of the barcoding region of the mitochondrial gene CO1 confirmed that all C. albicans reared from winter moth matched the C. albicans collected from Vancouver Island and were distinct from parasitic flies (presumably a native species) reared from a native congener of winter moth, Bruce spanworm (O. bruceata). Successful establishment of C. albicans on winter moth represents a rare, if not the only, example of the biological control of a major forest defoliator that attacks a wide range of tree species anywhere in the world by the establishment of a single specialist natural enemy.
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Identification of winter moth (Operophtera brumata) refugia in North Africa and the Italian Peninsula during the last glacial maximum.
Ecology and evolution, 2019Co-Authors: Jeremy C. Andersen, Yaussra Mannai, Olfa Ezzine, Mohamed Lahbib Ben Jamâa, Nathan P. Havill, Adalgisa Caccone, Samir Dhahri, Joseph S. ElkintonAbstract:Numerous studies have shown that the genetic diversity of species inhabiting temperate regions has been shaped by changes in their distributions during the Quaternary climatic oscillations. For some species, the genetic distinctness of isolated populations is maintained during secondary contact, while for others, admixture is frequently observed. For the winter moth (Operophtera brumata), an important defoliator of oak forests across Europe and northern Africa, we previously determined that contemporary populations correspond to genetic diversity obtained during the last glacial maximum (LGM) through the use of refugia in the Iberian and Aegean peninsulas, and to a lesser extent the Caucasus region. Missing from this sampling were populations from the Italian peninsula and from North Africa, both regions known to have played important roles as glacial refugia for other species. Therefore, we genotyped field-collected winter moth individuals from southern Italy and northwestern Tunisia-the latter a region where severe oak forest defoliation by winter moth has recently been reported-using polymorphic microsatellite. We reconstructed the genetic relationships of these populations in comparison to moths previously sampled from the Iberian and Aegean peninsulas, the Caucasus region, and western Europe using genetic distance, Bayesian clustering, and approximate Bayesian computation (ABC) methods. Our results indicate that both the southern Italian and the Tunisian populations are genetically distinct from other sampled populations, and likely originated in their respective refugium during the LGM after diverging from a population that eventually settled in the Iberian refugium. These suggest that winter moth populations persisted in at least five Mediterranean LGM refugia. Finally, we comment that outbreaks by winter moth in northwestern Tunisia are not the result of a recent introduction of a nonnative species, but rather are most likely due to land use or environmental changes.
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Identification and impact of hyperparasitoids and predators affecting Cyzenis albicans (Tachinidae), a recently introduced biological control agent of winter moth (Operophtera brumata L.) in the northeastern U.S.A.
Biological Control, 2018Co-Authors: Hannah J. Broadley, Joseph S. Elkinton, Emily A. Kelly, Robert R. Kula, George H. BoettnerAbstract:Abstract The success or failure of an introduced biological control agent may depend on its rate of mortality from disease, predation, and hyperparasitism. Cyzenis albicans Fallen (Diptera: Tachinidae) was introduced to the northeastern U.S. as a biocontrol agent of the invasive species winter moth, Operophtera brumata L. (Lepidoptera: Geometridae). This study aimed to determine the rates of mortality from predation by generalist ground predators and hyperparasitism of C. albicans puparia, identify any hyperparasitoids, and assess the impact of predation and hyperparasitism on the potential success of C. albicans in controlling the winter moth. Mortality of C. albicans puparia was primarily due to predation, but there was also hyperparasitism. Predation and parasitism of C. albicans puparia were consistently high across the six study sites and two years of study, but somewhat lower than was reported from British Columbia, where successful establishment of C. albicans in the 1970s was followed by a decrease in winter moth densities. In this study, three genera of ichneumonid hyperparasitoids were detected and identified using a combination of morphological and molecular approaches: Phygadeuon (1 species), Pimpla (2 species), and Gelis (2 species), all of which contain species with broad host ranges and were likely acting as facultative hyperparsitoids. We conclude that while total mortality of C. albicans puparia is high, it is unlikely to have a significant effect on biological control of winter moth in this system, although it may explain why C. albicans has been slow to establish in this region. Our study emphasizes the importance of assessing the mortality of introduced biological control agents caused by native predators and hyperparasitoids.
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Postglacial recolonization shaped the genetic diversity of the winter moth (Operophtera brumata) in Europe.
Ecology and evolution, 2017Co-Authors: Jeremy C. Andersen, Nathan P. Havill, Adalgisa Caccone, Joseph S. ElkintonAbstract:Changes in climate conditions, particularly during the Quaternary climatic oscillations, have long been recognized to be important for shaping patterns of species diversity. For species residing in the western Palearctic, two commonly observed genetic patterns resulting from these cycles are as follows: (1) that the numbers and distributions of genetic lineages correspond with the use of geographically distinct glacial refugia and (2) that southern populations are generally more diverse than northern populations (the "southern richness, northern purity" paradigm). To determine whether these patterns hold true for the widespread pest species the winter moth (Operophtera brumata), we genotyped 699 individual winter moths collected from 15 Eurasian countries with 24 polymorphic microsatellite loci. We find strong evidence for the presence of two major genetic clusters that diverged ~18 to ~22 ka, with evidence that secondary contact (i.e., hybridization) resumed ~ 5 ka along a well-established hybrid zone in Central Europe. This pattern supports the hypothesis that contemporary populations descend from populations that resided in distinct glacial refugia. However, unlike many previous studies of postglacial recolonization, we found no evidence for the "southern richness, northern purity" paradigm. We also find evidence for ongoing gene flow between populations in adjacent Eurasian countries, suggesting that long-distance dispersal plays an important part in shaping winter moth genetic diversity. In addition, we find that this gene flow is predominantly in a west-to-east direction, suggesting that recently debated reports of cyclical outbreaks of winter moth spreading from east to west across Europe are not the result of dispersal.
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The phylogenetic relationship and cross-infection of nucleopolyhedroviruses between the invasive winter moth (Operophtera brumata) and its native congener, Bruce spanworm (O. bruceata)
Journal of invertebrate pathology, 2016Co-Authors: Hannah J. Broadley, John P. Burand, Matthew Boucher, Joseph S. ElkintonAbstract:Disease can affect biological invasions by acting as either a synergist or antagonist. Disease-mediated invasions have important implications for understanding the spread of invasive insects, which cost billions of dollars in damages annually. One such non-native, destructive insect is the winter moth, Operophtera brumata L. (Lepidoptera: Geometridae), which causes defoliation and mortality of deciduous trees in its introduced range. In the northeastern United States, winter moth populations overlap with a native congener, Bruce spanworm, Operophtera bruceata Hulst. Nucleopolyhedrovirus (NPV), appears to be an important natural enemy in Bruce spanworm and there is some evidence that the NPV infection found in winter moth in the northeastern U.S. may originate from Bruce spanworm. By sequencing two viral genes (the polyhedrin and p74 genes) from field-collected larvae of both species, we found that the winter moth virus (OpbuNPV) is distinct from the virus from Bruce spanworm (OpbrNPV). However, the two viruses do constitute a clade within the Alphabaculovirus Group 2 NPVs, indicating that they are more similar to each other than they are to other lepidopteran viruses, even other geometrid-derived NPVs. As far as we know, this is the first report of sequences from an NPV from Bruce spanworm. Results from cross infection trials suggest that cross infection is uncommon if it occurs at all. Our results show that these two closely related species have distinct viruses and, unlike previous suggestions, Bruce spanworm virus is not mediating the winter moth invasion.
Rosemary S Hails - One of the best experts on this subject based on the ideXlab platform.
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Population genetic structure of the winter moth, Operophtera brumata Linnaeus, in the Orkney Isles suggests long-distance dispersal
Ecological Entomology, 2011Co-Authors: Helen C. Leggett, Rosemary S Hails, Steven M. Sait, Edward Owen Jones, Terry Burke, Mike BootsAbstract:The application of population genetic analysis and molecular ecological approaches allows us to examine the invasion of species in the wild. In particular, we can gain an insight into the role of dispersal, a key determinant of the invasion and population dynamics of important pest species. Since the 1980s, severe outbreaks of the winter moth, Operophtera brumata (Linnaeus), have caused extensive damage to heather moorlands in the Orkney Isles. The population genetic structure of O. brumata in Orkney was examined in order to establish whether the widely dispersed outbreaking populations are connected. 2. Amplified fragment length polymorphism (AFLP) analysis showed a high level of genetic diversity within subpopulations. This is consistent with an initial mass colonisation event and/or continuing dispersal between populations of O. brumata in Orkney. 3. Genetic differentiation among populations is low, and although some weak isolation by distance is detectable, no effect of isolation as a result of a sea barrier was found. High gene flow between populations is consistent with the low genetic differentiation observed, although there is evidence to suggest that the populations are not panmictic. 4. Given the limited dispersal of adults, the present results suggest that larvae may disperse over considerable distances by ballooning on strong winds across the Orkney Isles.
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Sequence analysis of a reovirus isolated from the winter moth Operophtera brumata (Lepidoptera: Geometridae) and its parasitoid wasp Phobocampe tempestiva (Hymenoptera: Ichneumonidae)
Virus Research, 2008Co-Authors: Robert I. Graham, Houssam Attoui, Peter P. C. Mertens, Rosemary S Hails, Steven M. Sait, Robert D. PosseeAbstract:A reovirus was isolated from Operophtera brumata (ObRV) and its parasitoid wasp Phobocampe tempestiva. Each of the 10 dsRNA genome segments of ObRV was sequenced and shown to contain a single open reading frame (ORF). Conserved motifs ([+ve] 5′-AAATAAA … G/TAGGTT-3′) were found at the termini of each segment, with the exception of Seg-6 and Seg-8, where the 5′ termini were 5′-AACAAA…-3′. The putative proteins encoded by each segment were compared with those of other members of the family Reoviridae. Phylogenetic comparisons to published sequences for the RNA-dependent RNA polymerase genes from other reoviruses indicated that ObRV is most closely related to members of the genus Cypovirus. However, unlike the cypoviruses, ObRV has a double-layered capsid structure. When the protein encoded by ObRV Seg-10 was expressed (by inserting the open reading frame into a baculovirus expression vector) no ‘occlusion bodies’ were observed in the recombinant baculovirus infected insect cell cultures. This suggests that unlike the cypoviruses, Seg-10 of ObRV does not contain a polyhedrin gene. Further phylogenetic comparisons also identified relationships between Seg-2 and Seg-10 of ObRV, and genes of Diadromus pulchellus Idnoreovirus 1 (DpIRV1), suggesting that ObRV represents a new species from the genus Idnoreovirus.
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Characterisation and partial sequence analysis of two novel cypoviruses isolated from the winter moth Operophtera brumata (Lepidoptera: Geometridae)
Virus Genes, 2007Co-Authors: Robert I. Graham, Peter P. C. Mertens, Rosemary S Hails, Steven M. Sait, Robert D. PosseeAbstract:The complete nucleotide sequences of genomic segments S5 to S10 from Operophtera brumata cypovirus 18 (OpbuCPV18), and the complete nucleotide sequences of genomic segments S2, S5, S9 and S10 from Operophtera brumata cypovirus 19 (OpbuCPV19) have been determined. Each genome segment contained a single open reading frame (ORF). Conserved motifs 5′ (AGUAAA....GUUAGCU) 3′ were found at the ends of each segment of OpbuCPV18, whilst conserved motifs 5′ (AACAAA....UUUGC) 3′ were found at each segment terminus of OpbuCPV19. The putative proteins were compared with those of other members of the Reoviridae family. Phylogenetic analysis using the polyhedrin gene (S10) indicated that OpbuCPV18 was most closely related to Dendrolimus punctatus cypovirus 1, whilst OpbuCPV19 was most closely related to Trichoplusia ni cypovirus 15. In addition, analysis of S2, which encoded a putative RNA-dependant RNA polymerase gene, confirmed OpbuCPV19 belonged to the genus Cypovirus . Following the expression of the ORF from OpbuCPV19 S10, using a baculovirus expression vector, occlusion bodies were observed in insect cell culture. This demonstrated that segment 10 coded for the polyhedrin gene, capable of forming a polyhedral crystalline matrix.
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Detection and characterisation of three novel species of reovirus (Reoviridae), isolated from geographically separate populations of the winter moth Operophtera brumata on Orkney
2006Co-Authors: Robert I. Graham, Robert D. Possee, Peter P. C. Mertens, Steven M. Sait, Shujing Rao, Rosemary S HailsAbstract:Geographically separate populations of winter moth (Operophtera brumata L.) were sampled in heather habitats on the Orkney Isles in order to investigate the prevalence of virus pathogens. Reoviruses were isolated in 11 of the 13 winter moth populations sampled, with 3 novel species being detected. Two species of Cypoviridae (CPV) were isolated, Operophtera brumata CPV18 and O. brumata CPV19, with one host population suffering 46% infection prevalence of OpbuCPV19. A third virus, O. brumata Reovirus (OpbuRV), was isolated from both winter moth and a hymenopteran parasitoid wasp, Phobocampe tempestiva, which is abundant in these populations. This was identified as a non-occluded reovirus, which was clearly able to infect and persist in both the lepidopteran and the hymenopteran host. The genomes of the three viruses were characterised using gel electrophoresis and the virus structure was investigated using transmission electron microscopy. The relationship of these viruses with a baculovirus that also infects winter moth, OpbuNPV, was investigated, as well as the association of OpbuRV with P. tempestiva. The detection of such viruses is discussed with reference to studies of similar viruses in other lepidopteran and hymenopteran host systems.
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Genetically variable nucleopolyhedroviruses isolated from spatially separate populations of the winter moth Operophtera brumata (Lepidoptera: Geometridae) in Orkney.
Journal of invertebrate pathology, 2004Co-Authors: Robert I. Graham, Robert D. Possee, Steven M. Sait, William I. Tyne, Rosemary S HailsAbstract:Here we report a lepidopteran system in which a pathogen is both abundant and genotypically variable. Geographically separate populations of winter moth (Operophtera brumata L.) were sampled in heather habitats on the Orkney Isles to investigate the prevalence of a pathogen, O. brumata Nucleopolyhedrovirus (OpbuNPV), within the natural system. Virus was recorded in 11 of the 13 winter moth populations sampled, with two populations suffering mortality due to virus at levels of ⩾50%. The virus genome from 200 single insect isolations was investigated for variation using restriction endonuclease digests. Twenty-six variants of OpbuNPV were detected using SalI. The polyhedrin gene of the virus was partially sequenced, allowing the relationship between the 26 variants to be portrayed as a cladogram. The phylogenetic relationship between OpbuNPV and other known baculovirus polyhedrin gene sequences was also established. The discovery of virus at such high prevalence is discussed with reference to occurrence and genetic variation of pathogens in other lepidopteran host populations. This study shows encouraging results for further studies into the role of pathogens in the regulation of host insect populations.
Helena Bylund - One of the best experts on this subject based on the ideXlab platform.
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waves and synchrony in epirrita autumnata Operophtera brumata outbreaks ii sunspot activity cannot explain cyclic outbreaks
Journal of Animal Ecology, 2007Co-Authors: Arne C. Nilssen, Olle Tenow, Helena BylundAbstract:1. In recent studies, it has been argued that sunspot activity forces the Epirrita autumnata 9-10-year outbreak periodicity in the mountain birch forest of Fennoscandia. For the following reasons, we challenge this conclusion. 2. With a 10-year outbreak cycle of E. autumnata and the 11-year sunspot cycle, it is expected that the cycles will run in-phase, out-of-phase and in-phase within 10 x 11 years. Hence, given such cycle lengths, sunspot activity should not affect outbreak periods. For a test, the E. autumnata series should be at least 110 years in length. 3. A well-documented E. autumnata outbreak series of 81 years (1888-1968; outbreak periods IV-XII) exists. This series is here lengthened to 114 years by adding outbreak frequencies for three decades (1969-2001). 4. By lengthening the series, three more E. autumnata/Operophtera brumata periods (XIII, XIV, XV) are identified. Period XV, like several earlier periods, was of the moving type, i.e. outbreaks moved in a wavelike manner from northern Fennoscandia to southern Norway. 5. As with several earlier outbreak periods in central northern Fennoscandia, the main timing of periods XIII-XV centred at the middle of the decades. In contrast, outbreaks at the extreme north-western coast of Norway centred at the decadal shifts, i.e. about 1979, 1989 and 1999. Supported by historical documents, we explain the 1979 and 1999 outbreaks as the final expressions of east-west outbreak waves that branched off from the main waves which moved southward during periods XIII and XV. These side-waves in the north are new observations. Outbreaks at the decadal shift 1989/1990 may have been of a more complex nature. 6. We find that sunspot activity does not explain outbreak waves. Furthermore, a test of our 114-year long E. autumnata series against the contemporaneous sunspot series shows that the two series run in-phase and out-of-phase. The observed interval between the two cycles coming in-phase agrees with the expected interval. This challenges the hypothesis of sunspot synchronization of the E. autumnata (and O. brumata) outbreaks.
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waves and synchrony in epirrita autumnata Operophtera brumata outbreaks i lagged synchrony regionally locally and among species
Journal of Animal Ecology, 2007Co-Authors: Olle Tenow, Arne C. Nilssen, Helena Bylund, O. HogstadAbstract:Summary 1 In 1990–2003, during a complete 10-year outbreak cycle, the synchrony of the birch defoliating outbreaks of the geometrids Epirrita autumnata and Operophtera brumata was studied quantitatively in the northern part of the Fennoscandian mountain chain (the Scandes). Data were supplemented with similar data from 1964 to 1966 and historical information. A 30-year series of field data from one locality in southern Scandes made possible interregional comparisons. 2 In 1991, outbreaks started in north-eastern Fennoscandia and moved westward like a wave and reached the outer coast of north-western Norway in about 2000. This wave is a new observation. In the same years, a previously documented outbreak wave moved southward along the Scandes. 3 Outbreak periods have usually occurred around the middle of each decade. Seemingly unrelated population peaks at the decadal shift 2000 were reported from islands at the coast of north-western Norway. They are shown here to have been the final ripples of the east–west wave. 4 At some localities, O. brumata peaked 2 years after E. autumnata. A lag of 1 or 2 years also occurred at the locality in southern Scandes. This interspecific time lag is a new observation. In accordance with the north–south wave, a time-lag of 1–2 years occurred between the fluctuations of northern and southern E. autumnata and O. brumata populations. 5 The population peak of E. autumnata occurred 1 year earlier at one locality than at a nearby locality. This pattern and particular altitudinal shifts of the O. brumata population density at these localities repeated in two outbreak periods. This indicates that, for example, local climate may modify outbreak synchrony between nearby localities. 6 At the same localities, O. brumata peaked first at one altitude and 1 or 2 years later at another altitude. This vertical lag is a new observation. 7 E. autumnata shows fluctuation traits similar to some other cyclic animals, e.g. the larch budmoth in the European Alps, some European tetraonid birds and the Canadian snow-shoe hare. These similarities (and dissimilarities) in intra- and interspecific synchronies and causes of E. autumnata and O. brumata synchronies, regionally, locally and among the two species are discussed.
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Waves and synchrony in Epirrita autumnata/Operophtera brumata outbreaks. II. Sunspot activity cannot explain cyclic outbreaks.
The Journal of animal ecology, 2007Co-Authors: Arne C. Nilssen, Olle Tenow, Helena BylundAbstract:1. In recent studies, it has been argued that sunspot activity forces the Epirrita autumnata 9-10-year outbreak periodicity in the mountain birch forest of Fennoscandia. For the following reasons, we challenge this conclusion. 2. With a 10-year outbreak cycle of E. autumnata and the 11-year sunspot cycle, it is expected that the cycles will run in-phase, out-of-phase and in-phase within 10 x 11 years. Hence, given such cycle lengths, sunspot activity should not affect outbreak periods. For a test, the E. autumnata series should be at least 110 years in length. 3. A well-documented E. autumnata outbreak series of 81 years (1888-1968; outbreak periods IV-XII) exists. This series is here lengthened to 114 years by adding outbreak frequencies for three decades (1969-2001). 4. By lengthening the series, three more E. autumnata/Operophtera brumata periods (XIII, XIV, XV) are identified. Period XV, like several earlier periods, was of the moving type, i.e. outbreaks moved in a wavelike manner from northern Fennoscandia to southern Norway. 5. As with several earlier outbreak periods in central northern Fennoscandia, the main timing of periods XIII-XV centred at the middle of the decades. In contrast, outbreaks at the extreme north-western coast of Norway centred at the decadal shifts, i.e. about 1979, 1989 and 1999. Supported by historical documents, we explain the 1979 and 1999 outbreaks as the final expressions of east-west outbreak waves that branched off from the main waves which moved southward during periods XIII and XV. These side-waves in the north are new observations. Outbreaks at the decadal shift 1989/1990 may have been of a more complex nature. 6. We find that sunspot activity does not explain outbreak waves. Furthermore, a test of our 114-year long E. autumnata series against the contemporaneous sunspot series shows that the two series run in-phase and out-of-phase. The observed interval between the two cycles coming in-phase agrees with the expected interval. This challenges the hypothesis of sunspot synchronization of the E. autumnata (and O. brumata) outbreaks.
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Waves and synchrony in Epirrita autumnata/Operophtera brumata outbreaks. I. Lagged synchrony: regionally, locally and among species.
The Journal of animal ecology, 2007Co-Authors: Olle Tenow, Arne C. Nilssen, Helena Bylund, O. HogstadAbstract:Summary 1 In 1990–2003, during a complete 10-year outbreak cycle, the synchrony of the birch defoliating outbreaks of the geometrids Epirrita autumnata and Operophtera brumata was studied quantitatively in the northern part of the Fennoscandian mountain chain (the Scandes). Data were supplemented with similar data from 1964 to 1966 and historical information. A 30-year series of field data from one locality in southern Scandes made possible interregional comparisons. 2 In 1991, outbreaks started in north-eastern Fennoscandia and moved westward like a wave and reached the outer coast of north-western Norway in about 2000. This wave is a new observation. In the same years, a previously documented outbreak wave moved southward along the Scandes. 3 Outbreak periods have usually occurred around the middle of each decade. Seemingly unrelated population peaks at the decadal shift 2000 were reported from islands at the coast of north-western Norway. They are shown here to have been the final ripples of the east–west wave. 4 At some localities, O. brumata peaked 2 years after E. autumnata. A lag of 1 or 2 years also occurred at the locality in southern Scandes. This interspecific time lag is a new observation. In accordance with the north–south wave, a time-lag of 1–2 years occurred between the fluctuations of northern and southern E. autumnata and O. brumata populations. 5 The population peak of E. autumnata occurred 1 year earlier at one locality than at a nearby locality. This pattern and particular altitudinal shifts of the O. brumata population density at these localities repeated in two outbreak periods. This indicates that, for example, local climate may modify outbreak synchrony between nearby localities. 6 At the same localities, O. brumata peaked first at one altitude and 1 or 2 years later at another altitude. This vertical lag is a new observation. 7 E. autumnata shows fluctuation traits similar to some other cyclic animals, e.g. the larch budmoth in the European Alps, some European tetraonid birds and the Canadian snow-shoe hare. These similarities (and dissimilarities) in intra- and interspecific synchronies and causes of E. autumnata and O. brumata synchronies, regionally, locally and among the two species are discussed.
Marinko Sremac - One of the best experts on this subject based on the ideXlab platform.
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Invasion spread of Operophtera brumata in northeastern United States and hybridization with O. bruceata
Biological Invasions, 2014Co-Authors: Joseph S. Elkinton, George H. Boettner, Andrew Liebhold, Marinko SremacAbstract:We used five methods to estimate the rate of spread of the winter moth, Operophtera brumata L., a European Lepidoptera, invading the northeastern USA and occasionally hybridizing with the closely related O. bruceata . These two species utilize the same sex attractant and pheromone traps capture both species. We estimated spread based on the ratio of the two species captured in pheromone-baited traps. Population boundaries were derived from captures in a grid of traps and spread was estimated as 6.6 km/year based on displacement of population boundaries between 2005 and 2008. Radial spread rate was also estimated as 6.9 km/year from the displacement of boundaries using logistic regression of trap captures along a single east–west transect of traps deployed yearly from 2007 to 2011. We also estimated the rate of spread from the expansion of defoliation mapped during aerial surveys. Based on the displacement of defoliation boundaries from 2005 to 2008, spread rate was estimated as 6.0 km/year. Based on the year of first defoliation, spread was estimated as 4.8 km/year and regression of the square-root of the cumulative area/π versus time yielded an estimate of 4.7 km/year. All five estimates were similar, and differences reflect the nuances of the data from which they were derived. We discuss here how the occasional hybridization with O. bruceata may be either retarding or enhancing O. brumata spread.
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Phylogeographic diversity of the winter moths Operophtera brumata and O. bruceata (Lepidoptera: Geometridae) in Europe and North America.
Annals of the Entomological Society of America, 2013Co-Authors: Rodger A. Gwiazdowski, Joseph S. Elkinton, Jeremy R Dewaard, Marinko SremacAbstract:ABSTRACT The European winter moth, Operophtera brumata (L.), an invasive forest defoliator, is undergoing a rapid range expansion in northeastern North America. The source of this invasion, and phylogeographic diversity throughout its native range, has not been explored. To do this, we used samples from a pheromone-baited trap survey of O. brumata collected across its native range in Europe, and invasive range in North America. Traps in North America also attract a congeneric species, the Bruce spanworm O. bruceata (Hulst), and the western Bruce spanworm O. b. occidentalis (Hulst). From this sampling, we sequenced two regions of the cytochrome c oxidase subunit I mitochondrial gene; one region corresponds to the DNA ‘barcode’ region, the other is a nonoverlapping section. We used these sequences, in combination with sequence data from a recent survey of the Geometridae in western North America, for phylogenetic and phylogeographic analyses to characterize genetic divergence and variation for O. brumata in...
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Hourly and seasonable variation in catch of winter moths and bruce spanworm in pheromone-baited traps
2011Co-Authors: Joseph S. Elkinton, George H. Boettner, Roy Hunkins, Natalie Leva, Marinko SremacAbstract:Elkinton et al. recently completed a survey of northeastern North America for the newly invasive winter moth, Operophtera brumata L. The survey used traps baited with the winter moth pheromone, which, as far as it is known, consists of a single compound that is also used by Bruce spanworm, the North American congener of winter moth, O. bruceata (Hulst).
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DNA analysis of the origins of winter moth in New England
2011Co-Authors: Joseph S. Elkinton, Rodger A. Gwiazdowski, Marinko Sremac, Roy Hunkins, George H. BoettnerAbstract:Elkinton et al recently completed a survey of northeastern North America for the newly invasive winter moth, Operophtera brumata L. The survey used traps baited with the winter moth pheromone, which, as far as it is known, consists of a single compound that is also used by Bruce spanworm, the North American congener of winter moth, O. bruceata (Hulst).
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Update on winter moth in New England
2009Co-Authors: Joseph S. Elkinton, Emily Hibbard, George H. Boettner, Rodger A. Gwiazdowski, Marinko Sremac, Roy Hunkins, Adam H. PorterAbstract:The winter moth, Operophtera brumata, a leaf-feeding geometrid native to Europe, has recently invaded eastern New England and is causing widespread defoliation. Previous invasions by this species in Nova Scotia and British Columbia have been suppressed by the introduction of two parasitoids from Europe, the tachinid Cyzenis albicans and the ichneumonid, Agrypon flaveolatum.
Robert D. Possee - One of the best experts on this subject based on the ideXlab platform.
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Sequence analysis of a reovirus isolated from the winter moth Operophtera brumata (Lepidoptera: Geometridae) and its parasitoid wasp Phobocampe tempestiva (Hymenoptera: Ichneumonidae)
Virus Research, 2008Co-Authors: Robert I. Graham, Houssam Attoui, Peter P. C. Mertens, Rosemary S Hails, Steven M. Sait, Robert D. PosseeAbstract:A reovirus was isolated from Operophtera brumata (ObRV) and its parasitoid wasp Phobocampe tempestiva. Each of the 10 dsRNA genome segments of ObRV was sequenced and shown to contain a single open reading frame (ORF). Conserved motifs ([+ve] 5′-AAATAAA … G/TAGGTT-3′) were found at the termini of each segment, with the exception of Seg-6 and Seg-8, where the 5′ termini were 5′-AACAAA…-3′. The putative proteins encoded by each segment were compared with those of other members of the family Reoviridae. Phylogenetic comparisons to published sequences for the RNA-dependent RNA polymerase genes from other reoviruses indicated that ObRV is most closely related to members of the genus Cypovirus. However, unlike the cypoviruses, ObRV has a double-layered capsid structure. When the protein encoded by ObRV Seg-10 was expressed (by inserting the open reading frame into a baculovirus expression vector) no ‘occlusion bodies’ were observed in the recombinant baculovirus infected insect cell cultures. This suggests that unlike the cypoviruses, Seg-10 of ObRV does not contain a polyhedrin gene. Further phylogenetic comparisons also identified relationships between Seg-2 and Seg-10 of ObRV, and genes of Diadromus pulchellus Idnoreovirus 1 (DpIRV1), suggesting that ObRV represents a new species from the genus Idnoreovirus.
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Characterisation and partial sequence analysis of two novel cypoviruses isolated from the winter moth Operophtera brumata (Lepidoptera: Geometridae)
Virus Genes, 2007Co-Authors: Robert I. Graham, Peter P. C. Mertens, Rosemary S Hails, Steven M. Sait, Robert D. PosseeAbstract:The complete nucleotide sequences of genomic segments S5 to S10 from Operophtera brumata cypovirus 18 (OpbuCPV18), and the complete nucleotide sequences of genomic segments S2, S5, S9 and S10 from Operophtera brumata cypovirus 19 (OpbuCPV19) have been determined. Each genome segment contained a single open reading frame (ORF). Conserved motifs 5′ (AGUAAA....GUUAGCU) 3′ were found at the ends of each segment of OpbuCPV18, whilst conserved motifs 5′ (AACAAA....UUUGC) 3′ were found at each segment terminus of OpbuCPV19. The putative proteins were compared with those of other members of the Reoviridae family. Phylogenetic analysis using the polyhedrin gene (S10) indicated that OpbuCPV18 was most closely related to Dendrolimus punctatus cypovirus 1, whilst OpbuCPV19 was most closely related to Trichoplusia ni cypovirus 15. In addition, analysis of S2, which encoded a putative RNA-dependant RNA polymerase gene, confirmed OpbuCPV19 belonged to the genus Cypovirus . Following the expression of the ORF from OpbuCPV19 S10, using a baculovirus expression vector, occlusion bodies were observed in insect cell culture. This demonstrated that segment 10 coded for the polyhedrin gene, capable of forming a polyhedral crystalline matrix.
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Detection and characterisation of three novel species of reovirus (Reoviridae), isolated from geographically separate populations of the winter moth Operophtera brumata on Orkney
2006Co-Authors: Robert I. Graham, Robert D. Possee, Peter P. C. Mertens, Steven M. Sait, Shujing Rao, Rosemary S HailsAbstract:Geographically separate populations of winter moth (Operophtera brumata L.) were sampled in heather habitats on the Orkney Isles in order to investigate the prevalence of virus pathogens. Reoviruses were isolated in 11 of the 13 winter moth populations sampled, with 3 novel species being detected. Two species of Cypoviridae (CPV) were isolated, Operophtera brumata CPV18 and O. brumata CPV19, with one host population suffering 46% infection prevalence of OpbuCPV19. A third virus, O. brumata Reovirus (OpbuRV), was isolated from both winter moth and a hymenopteran parasitoid wasp, Phobocampe tempestiva, which is abundant in these populations. This was identified as a non-occluded reovirus, which was clearly able to infect and persist in both the lepidopteran and the hymenopteran host. The genomes of the three viruses were characterised using gel electrophoresis and the virus structure was investigated using transmission electron microscopy. The relationship of these viruses with a baculovirus that also infects winter moth, OpbuNPV, was investigated, as well as the association of OpbuRV with P. tempestiva. The detection of such viruses is discussed with reference to studies of similar viruses in other lepidopteran and hymenopteran host systems.
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Genetically variable nucleopolyhedroviruses isolated from spatially separate populations of the winter moth Operophtera brumata (Lepidoptera: Geometridae) in Orkney.
Journal of invertebrate pathology, 2004Co-Authors: Robert I. Graham, Robert D. Possee, Steven M. Sait, William I. Tyne, Rosemary S HailsAbstract:Here we report a lepidopteran system in which a pathogen is both abundant and genotypically variable. Geographically separate populations of winter moth (Operophtera brumata L.) were sampled in heather habitats on the Orkney Isles to investigate the prevalence of a pathogen, O. brumata Nucleopolyhedrovirus (OpbuNPV), within the natural system. Virus was recorded in 11 of the 13 winter moth populations sampled, with two populations suffering mortality due to virus at levels of ⩾50%. The virus genome from 200 single insect isolations was investigated for variation using restriction endonuclease digests. Twenty-six variants of OpbuNPV were detected using SalI. The polyhedrin gene of the virus was partially sequenced, allowing the relationship between the 26 variants to be portrayed as a cladogram. The phylogenetic relationship between OpbuNPV and other known baculovirus polyhedrin gene sequences was also established. The discovery of virus at such high prevalence is discussed with reference to occurrence and genetic variation of pathogens in other lepidopteran host populations. This study shows encouraging results for further studies into the role of pathogens in the regulation of host insect populations.