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S. Bjørnson - One of the best experts on this subject based on the ideXlab platform.
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effects of temperature on larval development alkaloid production and microsporidiosis in the two spotted lady beetle Adalia bipunctata l coleoptera coccinellidae
Journal of Invertebrate Pathology, 2020Co-Authors: T. Steele, R.d. Singer, S. BjørnsonAbstract:Abstract Nosema Adaliae, a microsporidian pathogen described from the two-spotted lady beetle, Adalia bipunctata L., delays larval development when A. bipunctata is reared under laboratory conditions at 25 °C. In nature, lady beetles often experience a wide range of environmental temperatures, but little is known regarding the effects of microsporidian pathogens on lady beetles when they are reared at higher and lower temperatures. In this study, the effects of elevated rearing temperatures and microsporidiosis were observed on larval development time and mortality, sex ratios, alkaloid content (adaline and adalinine), and adult morphometrics. Uninfected larvae (24 h-old) were provided either an uninfected or N. Adaliae-infected conspecific egg and subsequently reared at three temperatures (25 °C, 27.5 °C or 30 °C). After the egg was eaten, larvae were provided a diet of green peach aphids and their development was recorded daily. Following eclosion, a subsample of adults were photographed for microscopic measurements and reflex-fluid was collected for alkaloid analysis using gas chromatography-mass spectrometry. Afterwards, all individuals were examined to determine the number that had become infected, and the same subsample was used to assess the severity of infection. Development time was delayed significantly for larvae that consumed a N. Adaliae-infected egg, and infected larvae took significantly longer to develop at 25 °C than at 27.5 °C or 30 °C. No differences were observed for larval mortality or sex ratios. The relative proportion of adaline increased when larvae were reared at 30 °C, but adaline concentration was not affected by the pathogen, N. Adaliae. Adults reared at 25 °C had larger body measurements when compared to those reared at 27.5 °C and 30 °C. Overall, adults that had eaten a N. Adaliae-infected A. bipunctata egg as larvae had similar body measurements to those that ate an uninfected egg. When comparing male and female measurements, a significant interaction between infection status, temperature and sex was observed for elytra length and head capsule width only. These measurements were similar for uninfected and N. Adaliae-infected females across all temperatures. However, when reared at 25 °C, uninfected males had significantly smaller elytra and head capsules than did infected males; but when reared at 30 °C, no significant difference was observed for these measurements. Both percent infection and average spore count decreased at 27.5 °C and 30 °C. These results suggest that temperatures above 25 °C have a mitigating effect against N. Adaliae in A. bipunctata.
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Effects of food availability on microsporidiosis and alkaloid production in the two-spotted lady beetle, Adalia bipunctata L.
Journal of Invertebrate Pathology, 2020Co-Authors: T. Steele, R.d. Singer, S. BjørnsonAbstract:The effects of food availability and infection with the microsporidium Nosema Adaliae on alkaloid production in the two-spotted lady beetle, Adalia bipunctata L., was examined. Alkaloid production (relative percent adaline in reflex-fluid) and pathogen load (spore counts) were quantified for both uninfected and N. Adaliae-infected A. bipunctata. Alkaloid content was significantly higher for beetles fed irregularly than for those fed daily. For beetles infected with N. Adaliae, spore counts were significantly higher for those fed irregularly compared to those fed daily. These results suggest that adaline content in reflex-fluid is influenced by infection and that irregular food supply increases pathogen load.
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effects of microsporidiosis and food availability on the two spotted lady beetle Adalia bipunctata l and convergent lady beetle hippodamia convergens guerin meneville
Journal of Invertebrate Pathology, 2019Co-Authors: T. Steele, S. BjørnsonAbstract:Abstract Two species of microsporidia have been described from lady beetles that are commercially available for biological control: Nosema Adaliae from the two-spotted lady beetle, Adalia bipunctata L., and Tubulinosema hippodamiae from the convergent lady beetle, Hippodamia convergens Guerin-Meneville. These pathogens delay larval development under controlled conditions, but little is known regarding the effects that microsporidia cause when their hosts are subjected to stressful conditions that are often experienced in nature. In this study, the combined effects of microsporidiosis (N. Adaliae on A. bipunctata and T. hippodamiae on H. convergens) and irregular food availability were observed on host fitness (larval development and mortality, sex ratios, and adult morphometrics). For each beetle species, 24 h-old larvae were provided either an uninfected or microsporidia-infected conspecific egg. After the egg was eaten, some larvae were provided an abundance of aphids daily, whereas others were provided aphids on an irregular basis. Development was delayed significantly for larvae that consumed a microsporidia-infected egg, and for those fed irregularly. For A. bipunctata, a significant interaction was observed between infection status and food availability. This suggests that N. Adaliae-infected A. bipunctata larvae that have an irregular supply of aphids undergo further developmental delays than those with a generous food supply. This interaction was not observed for T. hippodamiae-infected H. convergens. For both species, larval mortality and sex ratios did not differ significantly, regardless of infection status or food availability. Adults that were fed daily as larvae were significantly larger than those fed irregularly. However, the elytra of N. Adaliae-infected A. bipunctata were significantly larger than the elytra of their uninfected cohorts, and T. hippodamiae-infected H. convergens had wider pronota and head capsules than uninfected H. convergens. Because N. Adaliae and T. hippodamiae prolong larval development of their respective hosts under controlled conditions, one would expect these pathogens to cause more profound effects when their hosts experience stressful conditions. The results from this study indicate that this was the case for A. bipunctata, but not for H. convergens.
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nosema Adaliae sp nov a new microsporidian pathogen from the two spotted lady beetle Adalia bipunctata l coleoptera coccinellidae and its relationship to microsporidia that infect other coccinellids
Journal of Invertebrate Pathology, 2014Co-Authors: T. Steele, S. BjørnsonAbstract:Abstract The two-spotted lady beetle, Adalia bipunctata L., is a tree-dwelling lady beetle endemic to parts of Europe, Central Asia and North America that is commercially available for aphid control in Europe and North America. Lady beetles host a wide variety of symbionts including parasitoids, viruses, eugregarines, fungi, bacteria, nematodes and microsporidia. Four species of microsporidia have been described from lady beetles, and an undescribed microsporidium was recently isolated from local populations of A. bipunctata in Nova Scotia, Canada. In a previous study, this pathogen prolonged the development of A. bipunctata larvae but had no effect on adult fecundity, longevity or sex ratios. The objective of this study was to formally describe the microsporidium by means of its ultrastructure, tissue pathology and molecular characterization. All stages of the microsporidium were diplokaryotic and developed in direct contact with the host cell cytoplasm. Mature spores measured 4.25 ± 0.09 × 1.82 ± 0.03 μm (SE, n = 49, from micrographs) and fresh spores measured 6.10 ± 0.06 × 3.01 ± 0.05 μm (±SE, n = 60; range: 5.0–6.9 × 2.18–3.86 μm). The polar filament was isofilar with 10–18 coils that were frequently arranged in a single row. The lamellar polaroplast was not typically visible and spores contained a relatively small posterior vacuole. Both the flight muscles and fat body were heavily infected and a large number of spores were observed within and between the cells of these tissues. The ovaries, developing oocytes, spermatocytes and accessory glands within the testes, midgut epithelium, Malpighian tubules, ileum, colon, and ventral nerve cord were also infected but not as heavily. Connective tissue near the cuticle and surrounding the trachea were lightly infected. The presence of spores in both the alimentary canal and ovaries (particularly within developing oocytes) suggests that the microsporidium can be transmitted per os (horizontally) and transovarially (vertically). Molecular analysis of the genome of the microsporidium described in this study was 97% similar to Nosema bombi and 96% similar to Nosema thomsoni, Nosema vespula and Nosema oulemae. Based on information gained during this study, we propose that the microsporidium in A. bipunctata be given the name Nosema Adaliae sp. nov.
T. Steele - One of the best experts on this subject based on the ideXlab platform.
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effects of temperature on larval development alkaloid production and microsporidiosis in the two spotted lady beetle Adalia bipunctata l coleoptera coccinellidae
Journal of Invertebrate Pathology, 2020Co-Authors: T. Steele, R.d. Singer, S. BjørnsonAbstract:Abstract Nosema Adaliae, a microsporidian pathogen described from the two-spotted lady beetle, Adalia bipunctata L., delays larval development when A. bipunctata is reared under laboratory conditions at 25 °C. In nature, lady beetles often experience a wide range of environmental temperatures, but little is known regarding the effects of microsporidian pathogens on lady beetles when they are reared at higher and lower temperatures. In this study, the effects of elevated rearing temperatures and microsporidiosis were observed on larval development time and mortality, sex ratios, alkaloid content (adaline and adalinine), and adult morphometrics. Uninfected larvae (24 h-old) were provided either an uninfected or N. Adaliae-infected conspecific egg and subsequently reared at three temperatures (25 °C, 27.5 °C or 30 °C). After the egg was eaten, larvae were provided a diet of green peach aphids and their development was recorded daily. Following eclosion, a subsample of adults were photographed for microscopic measurements and reflex-fluid was collected for alkaloid analysis using gas chromatography-mass spectrometry. Afterwards, all individuals were examined to determine the number that had become infected, and the same subsample was used to assess the severity of infection. Development time was delayed significantly for larvae that consumed a N. Adaliae-infected egg, and infected larvae took significantly longer to develop at 25 °C than at 27.5 °C or 30 °C. No differences were observed for larval mortality or sex ratios. The relative proportion of adaline increased when larvae were reared at 30 °C, but adaline concentration was not affected by the pathogen, N. Adaliae. Adults reared at 25 °C had larger body measurements when compared to those reared at 27.5 °C and 30 °C. Overall, adults that had eaten a N. Adaliae-infected A. bipunctata egg as larvae had similar body measurements to those that ate an uninfected egg. When comparing male and female measurements, a significant interaction between infection status, temperature and sex was observed for elytra length and head capsule width only. These measurements were similar for uninfected and N. Adaliae-infected females across all temperatures. However, when reared at 25 °C, uninfected males had significantly smaller elytra and head capsules than did infected males; but when reared at 30 °C, no significant difference was observed for these measurements. Both percent infection and average spore count decreased at 27.5 °C and 30 °C. These results suggest that temperatures above 25 °C have a mitigating effect against N. Adaliae in A. bipunctata.
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Effects of food availability on microsporidiosis and alkaloid production in the two-spotted lady beetle, Adalia bipunctata L.
Journal of Invertebrate Pathology, 2020Co-Authors: T. Steele, R.d. Singer, S. BjørnsonAbstract:The effects of food availability and infection with the microsporidium Nosema Adaliae on alkaloid production in the two-spotted lady beetle, Adalia bipunctata L., was examined. Alkaloid production (relative percent adaline in reflex-fluid) and pathogen load (spore counts) were quantified for both uninfected and N. Adaliae-infected A. bipunctata. Alkaloid content was significantly higher for beetles fed irregularly than for those fed daily. For beetles infected with N. Adaliae, spore counts were significantly higher for those fed irregularly compared to those fed daily. These results suggest that adaline content in reflex-fluid is influenced by infection and that irregular food supply increases pathogen load.
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effects of microsporidiosis and food availability on the two spotted lady beetle Adalia bipunctata l and convergent lady beetle hippodamia convergens guerin meneville
Journal of Invertebrate Pathology, 2019Co-Authors: T. Steele, S. BjørnsonAbstract:Abstract Two species of microsporidia have been described from lady beetles that are commercially available for biological control: Nosema Adaliae from the two-spotted lady beetle, Adalia bipunctata L., and Tubulinosema hippodamiae from the convergent lady beetle, Hippodamia convergens Guerin-Meneville. These pathogens delay larval development under controlled conditions, but little is known regarding the effects that microsporidia cause when their hosts are subjected to stressful conditions that are often experienced in nature. In this study, the combined effects of microsporidiosis (N. Adaliae on A. bipunctata and T. hippodamiae on H. convergens) and irregular food availability were observed on host fitness (larval development and mortality, sex ratios, and adult morphometrics). For each beetle species, 24 h-old larvae were provided either an uninfected or microsporidia-infected conspecific egg. After the egg was eaten, some larvae were provided an abundance of aphids daily, whereas others were provided aphids on an irregular basis. Development was delayed significantly for larvae that consumed a microsporidia-infected egg, and for those fed irregularly. For A. bipunctata, a significant interaction was observed between infection status and food availability. This suggests that N. Adaliae-infected A. bipunctata larvae that have an irregular supply of aphids undergo further developmental delays than those with a generous food supply. This interaction was not observed for T. hippodamiae-infected H. convergens. For both species, larval mortality and sex ratios did not differ significantly, regardless of infection status or food availability. Adults that were fed daily as larvae were significantly larger than those fed irregularly. However, the elytra of N. Adaliae-infected A. bipunctata were significantly larger than the elytra of their uninfected cohorts, and T. hippodamiae-infected H. convergens had wider pronota and head capsules than uninfected H. convergens. Because N. Adaliae and T. hippodamiae prolong larval development of their respective hosts under controlled conditions, one would expect these pathogens to cause more profound effects when their hosts experience stressful conditions. The results from this study indicate that this was the case for A. bipunctata, but not for H. convergens.
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nosema Adaliae sp nov a new microsporidian pathogen from the two spotted lady beetle Adalia bipunctata l coleoptera coccinellidae and its relationship to microsporidia that infect other coccinellids
Journal of Invertebrate Pathology, 2014Co-Authors: T. Steele, S. BjørnsonAbstract:Abstract The two-spotted lady beetle, Adalia bipunctata L., is a tree-dwelling lady beetle endemic to parts of Europe, Central Asia and North America that is commercially available for aphid control in Europe and North America. Lady beetles host a wide variety of symbionts including parasitoids, viruses, eugregarines, fungi, bacteria, nematodes and microsporidia. Four species of microsporidia have been described from lady beetles, and an undescribed microsporidium was recently isolated from local populations of A. bipunctata in Nova Scotia, Canada. In a previous study, this pathogen prolonged the development of A. bipunctata larvae but had no effect on adult fecundity, longevity or sex ratios. The objective of this study was to formally describe the microsporidium by means of its ultrastructure, tissue pathology and molecular characterization. All stages of the microsporidium were diplokaryotic and developed in direct contact with the host cell cytoplasm. Mature spores measured 4.25 ± 0.09 × 1.82 ± 0.03 μm (SE, n = 49, from micrographs) and fresh spores measured 6.10 ± 0.06 × 3.01 ± 0.05 μm (±SE, n = 60; range: 5.0–6.9 × 2.18–3.86 μm). The polar filament was isofilar with 10–18 coils that were frequently arranged in a single row. The lamellar polaroplast was not typically visible and spores contained a relatively small posterior vacuole. Both the flight muscles and fat body were heavily infected and a large number of spores were observed within and between the cells of these tissues. The ovaries, developing oocytes, spermatocytes and accessory glands within the testes, midgut epithelium, Malpighian tubules, ileum, colon, and ventral nerve cord were also infected but not as heavily. Connective tissue near the cuticle and surrounding the trachea were lightly infected. The presence of spores in both the alimentary canal and ovaries (particularly within developing oocytes) suggests that the microsporidium can be transmitted per os (horizontally) and transovarially (vertically). Molecular analysis of the genome of the microsporidium described in this study was 97% similar to Nosema bombi and 96% similar to Nosema thomsoni, Nosema vespula and Nosema oulemae. Based on information gained during this study, we propose that the microsporidium in A. bipunctata be given the name Nosema Adaliae sp. nov.
P O'donald - One of the best experts on this subject based on the ideXlab platform.
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Non-random mating in Adalia bipunctata (the two-spot ladybird). II. Further tests for female mating preference
Heredity, 1992Co-Authors: P W E Kearns, I P M Tomlinson, C J Veltman, P O'donaldAbstract:Tests for non-random mating in laboratory stocks of Adalia bipunctata showed that female two-spot ladybirds from ‘isofemale lines’, which had formerly mated preferentially with melanic males, now mated at random. In an attempt to obtain new stocks in which females mated preferentially, we isolated ‘isofemale lines’ from a natural population at Keele, but we found no evidence of females mating preferentially within these stocks. We did, however, observe two interesting phenomena, not previously reported from Keele populations of Adalia bipunctata , or from laboratory stocks derived from the Keele population. Firstly, much of the variation in male mating success, which we observed, could be explained by the date on which the mating tests were carried out. Secondly, there was significant heterogeneity in sex ratios among some of the stocks. We discuss the potential importance of both these phenomena when designing experiments and interpreting data regarding non-random mating in Adalia bipunctata .
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Non-random mating in Adalia bipunctata (the two-spot ladybird). III. New evidence of genetic preference
Heredity, 1992Co-Authors: P O'donald, Michael E. N. MajerusAbstract:Non-random mating in Adalia bipunctata (the two-spot ladybird). III. New evidence of genetic preference
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Non-random mating in Adalia bipunctata (the two-spot ladybird). II. Further tests for female mating preference
Heredity, 1992Co-Authors: P W E Kearns, I P M Tomlinson, C J Veltman, P O'donaldAbstract:Non-random mating in Adalia bipunctata (the two-spot ladybird). II. Further tests for female mating preference
Paul M. Brakefield - One of the best experts on this subject based on the ideXlab platform.
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Climate and change in clines for melanism in the two–spot ladybird, Adalia bipunctata (Coleoptera: Coccinellidae)
Proceedings of the Royal Society of London. Series B: Biological Sciences, 1998Co-Authors: Peter W. De Jong, Paul M. BrakefieldAbstract:The polymorphic two-spot ladybird, Adalia bipunctata, shows clinal variation in the frequency with which melanic and non-melanic morphs occur. Here we show that the clines in melanism in The Netherlands have changed over the past two decades: they have become shallower. This change has coincided with an increase in local ambient spring temperatures at most meteorological stations close to the sampling sites. The potential contribution of thermal melanism to the change in the shape of the clines is discussed.
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climate and change in clines for melanism in the two spot ladybird Adalia bipunctata coleoptera coccinellidae
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: Peter W. De Jong, Paul M. BrakefieldAbstract:The polymorphic two-spot ladybird, Adalia bipunctata, shows clinal variation in the frequency with which melanic and non-melanic morphs occur. Here we show that the clines in melanism in The Netherlands have changed over the past two decades: they have become shallower. This change has coincided with an increase in local ambient spring temperatures at most meteorological stations close to the sampling sites. The potential contribution of thermal melanism to the change in the shape of the clines is discussed.
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Sperm competition and melanic polymorphism in the 2-spot ladybird, Adalia bipunctata (Coleoptera, Coccinellidae)
Heredity, 1993Co-Authors: Peter W. De Jong, Michelle D Verhoog, Paul M. BrakefieldAbstract:Sperm competition and melanic polymorphism in the 2-spot ladybird, Adalia bipunctata (Coleoptera, Coccinellidae)
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The inheritance of a wingless character in the 2spot ladybird (Adalia bipunctata)
Entomologia Experimentalis et Applicata, 1993Co-Authors: Nicola M. Marples, Michelle D Verhoog, P. W. De Jong, Mart M. Ottenheim, Paul M. BrakefieldAbstract:A viable wingless 2spot ladybird Adalia bipunctata (L.) was found in the wild. Breeding through four generations revealed that the wingless trait was controlled by a recessive allele which displays variable levels of expression. The wingless ladybird is discussed in relation to its potential as a biocontrol agent. One ladybird also occurred in this stock which is suggestive of a supergene controlling the colour polymorphism in this species.
P W E Kearns - One of the best experts on this subject based on the ideXlab platform.
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Non-random mating in Adalia bipunctata (the two-spot ladybird). II. Further tests for female mating preference
Heredity, 1992Co-Authors: P W E Kearns, I P M Tomlinson, C J Veltman, P O'donaldAbstract:Tests for non-random mating in laboratory stocks of Adalia bipunctata showed that female two-spot ladybirds from ‘isofemale lines’, which had formerly mated preferentially with melanic males, now mated at random. In an attempt to obtain new stocks in which females mated preferentially, we isolated ‘isofemale lines’ from a natural population at Keele, but we found no evidence of females mating preferentially within these stocks. We did, however, observe two interesting phenomena, not previously reported from Keele populations of Adalia bipunctata , or from laboratory stocks derived from the Keele population. Firstly, much of the variation in male mating success, which we observed, could be explained by the date on which the mating tests were carried out. Secondly, there was significant heterogeneity in sex ratios among some of the stocks. We discuss the potential importance of both these phenomena when designing experiments and interpreting data regarding non-random mating in Adalia bipunctata .
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Non-random mating in Adalia bipunctata (the two-spot ladybird). II. Further tests for female mating preference
Heredity, 1992Co-Authors: P W E Kearns, I P M Tomlinson, C J Veltman, P O'donaldAbstract:Non-random mating in Adalia bipunctata (the two-spot ladybird). II. Further tests for female mating preference
