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Martin R Speight - One of the best experts on this subject based on the ideXlab platform.
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horse chestnut scale Pulvinaria regalis homoptera coccidae and urban host tree environment
Ecology, 1998Co-Authors: Martin R Speight, Rosemary S Hails, Marius Gilbert, Andrew FoggoAbstract:The analysis and explanation of the spatial distribution of organisms within a locality are problematic. This study uses a combination of standard analytical methods (Generalized Linear Interactive Modeling [GLIM]) with recently developed spatial statistical techniques (geostatistical analysis), on a model system of insect-plant interactions in an urban setting. Infestations of the horse chestnut scale, Pulvinaria regalis, were mapped on three tree species in Oxford, United Kingdom. Various tree parameters were measured, as were aspects of the site in which each tree was growing. Using general linear modeling and geostatistics, the distribution and intensity of scale populations were investigated in relation to these parameters. The trees were separated into those that showed no symptoms of lack of vigor and those that were clearly unhealthy. In both cases, the only parameter that explained much of the variance in the scale egg densities on trees was the impermeability of the substrate surface under the trees, such that as substrates became more impermeable to water and nutrients (for example, as a result of concrete or roadways), the higher were the pest densities on those trees. For the vigorous trees alone, an extra parameter, that of building distance, was also found to be significant, so that trees very close to buildings also showed high pest densities. The spatial dependence of scale insect eggs on trees was found to be anisotropic through the sample area, in the southwest/northeast direction, attributable to wind speed, direction, and canyon effects.
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reproductive capacity of the horse chestnut scale insect Pulvinaria regalis canard hom coccidae
Journal of Applied Entomology, 1994Co-Authors: Martin R SpeightAbstract:The surface area of pre-oviposition female scale insects was closely correlated with their dry and wet weight biomass, and was used as a convenient, indirect method of adult size assessment. Adult females at oviposition were on average bigger when in low density populations than those in high densities, an indication of intraspecific competition in the nymphal stage. Larger females were found to be more fecund (laid more eggs), and produced larger eggs, than smaller females. No significant differences were detected between fecundities of females which had fed as nymphs on different species of host tree, and the general adult size/fecundity relationship was of sigmoid form, indicative of a maximum reproductive potential, which was independent of host tree species. Comparisons with other Hemipteran species indicated the generalist nature of P. regalis, adapted to widespread dispersal and large first instar losses from populations.
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the impact of leaf feeding by nymphs of the horse chestnut scale Pulvinaria regalis canard hem coccidae on young host trees
Journal of Applied Entomology, 1991Co-Authors: Martin R SpeightAbstract:Abstract The impact of leaf-feeding nymphs of the horse chestnut scale insect, Pulvinaria regalis Canard (Hem., Coccidae), was investigated by manipulating population densities on young sycamore, lime and horse chestnut trees under experimental conditions. The effects of sap feeding on leaves by scale nymphs during the summer on shoot elongation and diameter, plus root biomass, were considered. Sycamores exhibited dramatic reductions in leader, lateral and bottom shoot elongation in the prescence of Pulvinaria nymphs in both years of the investigation. However, neither limes nor horse chestnuts showed significant changes, although data for limes qualitatively suggested increased growth when infested. In the main, diameter growth was unaffected. All three host tree species suffered significant reductions in root dry weight biomass when infested with scale nymphs. Zusammenfassung Zum Einflus des Befalls von Pulvinaria regalis Canard (Hom., Coccidae) auf junge Wirtsbaume Der Einflus der Saugschaden an Blattern junger Wirtsbaume (Ahorn, Linde und Roskastanie) durch Schildlausnymphen (Pulvinaria regalis) wurde bei unterschiedlichen Populationsdichten untersucht. Es wurden die Auswirkungen des Sommerbefalls auf Trieblange, Durchmesser und Wurzelbiomasse aufgenommen. In beiden Beobachtungsjahren zeigte sich bei Ahorn eine dramatische Reduktion der Leit- und Seitentriebe. Dagegen zeigten sich bei Linde und Roskastanie keine Veranderungen, obwohl die Daten fur Linde zunachst den Eindruck einer Wachstumsforderung durch Schildlausbefall erweckten. Das Durchmesserwachstum blieb meist unbeeinflust, dagegen verursachte der Schildlausbefall bei allen drei Wirtsbaumen eine signifikante Reduktion der Trockenbiomasse der Wurzeln.
A. A. Nahif - One of the best experts on this subject based on the ideXlab platform.
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Zum Vorkommen von Mikrosporidien, Endosymbionten und Viren in der Wolligen Napfschildlaus Pulvinaria regalis Canard (Homoptera: Coccidae)
Journal of Plant Diseases and Protection, 2004Co-Authors: C. Arnold, J. Hamacher, A. A. NahifAbstract:The present study aimed to investigate the occurrence of microsporidia, endosymbionts and viruses in the Horse Chestnut Scale Pulvinaria regalis Canard (Homoptera: Coccidae), an introduced pest insect of more than 65 different plant species. Microsporidia could not be detected neither in eggs nor in three nymphal stages or in the adult scales. The number of endosymbiotic organisms increased continuously during the development of P. regalis . Mycetocytes appeared in the first nymphal stage for the first time. Their number and size increase considerably within the following developmental stages, merging into a mycetome in the adult scales. Two virus-like particles (VLP) were detected by electron microscopy (TEM). One VLP of 30 nm diameter was of isometric shape and had no outer or inner structures. The other VLP was 65 to 70 nm in diameter, had a hexagonal outline and a core of 4560 nm in diameter. The classification of the VLPs is discussed. Ziel der vorliegenden Arbeit war es, das Vorkommen von Mikrosporidien, Endosymbionten und Viren in der Wolligen Napfschildlaus Pulvinaria regalis Canard (Homoptera: Coccidae), einem nach Europa eingeschleppten Schädling, der an mehr als 65 verschiedenen Pflanzenarten saugt, zu untersuchen. Mikrosporidien konnten weder in Eiern, noch in den drei Nymphenstadien oder in adulten Schildläusen nachgewiesen werden. Die Anzahl von Endosymbionten nahm kontinuierlich während der Entwicklung von P. regalis zu. Myzetozyten wurden erstmals vereinzelt in den Erst nymphe n beobachtet. Ihre Anzahl und Größe steigt in den weiteren Entwicklungsstadien stark an, in adulten Schildläusen treten die Myzetozyten zu einem Myzetom zusammen. Zwei virusähnliche Partikel (Virus-Like Particle-VLP) konnten durch Elektronenmikroskopie (TEM) in P. regalis nachgewiesen werden: ein isometrisches VLP ohne äußere und innere Strukturen mit 30 nm Durchmesser sowie ein VLP mit 65–70 nm Durchmesser, hexagonalem Umriss und einem Core-Durchmesser von 45–60 nm. Die Klassifizierung der VLPs wird diskutiert.
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zum vorkommen von mikrosporidien endosymbionten und viren in der wolligen napfschildlaus Pulvinaria regalis canard homoptera coccidae
Journal of Plant Diseases and Protection, 2004Co-Authors: C. Arnold, J. Hamacher, A. A. NahifAbstract:Ziel der vorliegenden Arbeit war es, das Vorkommen von Mikrosporidien, Endosymbionten und Viren in der Wolligen Napfschildlaus Pulvinaria regalis Canard (Homoptera: Coccidae), einem nach Europa eingeschleppten Schadling, der an mehr als 65 verschiedenen Pflanzenarten saugt, zu untersuchen. Mikrosporidien konnten weder in Eiern, noch in den drei Nymphenstadien oder in adulten Schildlausen nachgewiesen werden. Die Anzahl von Endosymbionten nahm kontinuierlich wahrend der Entwicklung von P. regalis zu. Myzetozyten wurden erstmals vereinzelt in den Erst nymphe n beobachtet. Ihre Anzahl und Grose steigt in den weiteren Entwicklungsstadien stark an, in adulten Schildlausen treten die Myzetozyten zu einem Myzetom zusammen. Zwei virusahnliche Partikel (Virus-Like Particle-VLP) konnten durch Elektronenmikroskopie (TEM) in P. regalis nachgewiesen werden: ein isometrisches VLP ohne ausere und innere Strukturen mit 30 nm Durchmesser sowie ein VLP mit 65–70 nm Durchmesser, hexagonalem Umriss und einem Core-Durchmesser von 45–60 nm. Die Klassifizierung der VLPs wird diskutiert.
Andrew Foggo - One of the best experts on this subject based on the ideXlab platform.
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horse chestnut scale Pulvinaria regalis homoptera coccidae and urban host tree environment
Ecology, 1998Co-Authors: Martin R Speight, Rosemary S Hails, Marius Gilbert, Andrew FoggoAbstract:The analysis and explanation of the spatial distribution of organisms within a locality are problematic. This study uses a combination of standard analytical methods (Generalized Linear Interactive Modeling [GLIM]) with recently developed spatial statistical techniques (geostatistical analysis), on a model system of insect-plant interactions in an urban setting. Infestations of the horse chestnut scale, Pulvinaria regalis, were mapped on three tree species in Oxford, United Kingdom. Various tree parameters were measured, as were aspects of the site in which each tree was growing. Using general linear modeling and geostatistics, the distribution and intensity of scale populations were investigated in relation to these parameters. The trees were separated into those that showed no symptoms of lack of vigor and those that were clearly unhealthy. In both cases, the only parameter that explained much of the variance in the scale egg densities on trees was the impermeability of the substrate surface under the trees, such that as substrates became more impermeable to water and nutrients (for example, as a result of concrete or roadways), the higher were the pest densities on those trees. For the vigorous trees alone, an extra parameter, that of building distance, was also found to be significant, so that trees very close to buildings also showed high pest densities. The spatial dependence of scale insect eggs on trees was found to be anisotropic through the sample area, in the southwest/northeast direction, attributable to wind speed, direction, and canyon effects.
Sunil Joshi - One of the best experts on this subject based on the ideXlab platform.
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Redescription of Pulvinaria indica Avasthi & Shafee, 1985 (Hemiptera: Coccomorpha: Coccidae) with new host and distribution records
Zootaxa, 2019Co-Authors: Sunil Joshi, R S Ramya, Omprakash Navik, S A Pawar, U B Hole, A B TambeAbstract:The soft scale Pulvinaria indica (Hemiptera: Coccomorpha: Coccidae) was described by Avasthi & Shafee in 1985 from four females collected on Duranta repens Linn. from Simhachalam, Visakhapatnam, Andhra Pradesh, India. The original description, however, was scanty and attempts to locate the type material were unsuccessful. To facilitate the identification and separation of P. indica from other similar species, we redescribe and illustrate the adult female, based on newly collected specimens found on an economically important new host plant. Management options in the event of its future occurrence are discussed briefly.
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redescription of Pulvinaria indica avasthi shafee 1985 hemiptera coccomorpha coccidae with new host and distribution records
Zootaxa, 2019Co-Authors: Sunil Joshi, R S Ramya, Omprakash Navik, S A Pawar, U B Hole, A B TambeAbstract:The soft scale Pulvinaria indica (Hemiptera: Coccomorpha: Coccidae) was described by Avasthi & Shafee in 1985 from four females collected on Duranta repens Linn. from Simhachalam, Visakhapatnam, Andhra Pradesh, India. The original description, however, was scanty and attempts to locate the type material were unsuccessful. To facilitate the identification and separation of P. indica from other similar species, we redescribe and illustrate the adult female, based on newly collected specimens found on an economically important new host plant. Management options in the event of its future occurrence are discussed briefly.
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first record of Pulvinaria urbicola cockerell hemiptera coccidae from india with a key to the indian species of Pulvinaria targioni tozzetti
Zootaxa, 2017Co-Authors: Sunil JoshiAbstract:The notoriously destructive and invasive soft scale, Pulvinaria urbicola Cockerell (Hemiptera: Coccidae), is recorded for the first time from India. This scale, with variable morphological appearance and similarities with other known scales of the same genus established in India, is redescribed to facilitate its identification and separation from other similar species. Information on its host range, natural enemies and distribution is provided. Management options in the event of an outbreak are discussed briefly. A key to the species of Pulvinaria Targioni Tozzetti in India is also provided. This new arrival warrants special attention in India as it is a potentially damaging plant pest and has a broad host range across many plant families.
A B Tambe - One of the best experts on this subject based on the ideXlab platform.
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redescription of Pulvinaria indica avasthi shafee 1985 hemiptera coccomorpha coccidae with new host and distribution records
Zootaxa, 2019Co-Authors: Sunil Joshi, R S Ramya, Omprakash Navik, S A Pawar, U B Hole, A B TambeAbstract:The soft scale Pulvinaria indica (Hemiptera: Coccomorpha: Coccidae) was described by Avasthi & Shafee in 1985 from four females collected on Duranta repens Linn. from Simhachalam, Visakhapatnam, Andhra Pradesh, India. The original description, however, was scanty and attempts to locate the type material were unsuccessful. To facilitate the identification and separation of P. indica from other similar species, we redescribe and illustrate the adult female, based on newly collected specimens found on an economically important new host plant. Management options in the event of its future occurrence are discussed briefly.
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Redescription of Pulvinaria indica Avasthi & Shafee, 1985 (Hemiptera: Coccomorpha: Coccidae) with new host and distribution records
Zootaxa, 2019Co-Authors: Sunil Joshi, R S Ramya, Omprakash Navik, S A Pawar, U B Hole, A B TambeAbstract:The soft scale Pulvinaria indica (Hemiptera: Coccomorpha: Coccidae) was described by Avasthi & Shafee in 1985 from four females collected on Duranta repens Linn. from Simhachalam, Visakhapatnam, Andhra Pradesh, India. The original description, however, was scanty and attempts to locate the type material were unsuccessful. To facilitate the identification and separation of P. indica from other similar species, we redescribe and illustrate the adult female, based on newly collected specimens found on an economically important new host plant. Management options in the event of its future occurrence are discussed briefly.
