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Scott N White - One of the best experts on this subject based on the ideXlab platform.
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Poecilus lucublandus (Coleoptera: Carabidae) and Pterostichus mutus Do Not Feed on Hair Fescue, Red Sorrel, and Poverty Oatgrass Seeds.
Journal of insect science (Online), 2019Co-Authors: Alexandre M M C Loureiro, Vilis O. Nams, G. Christopher Cutler, Scott N WhiteAbstract:Poecilus lucublandus (Say), Pterostichus mutus (Say), and Harpalus rufipes (De Geer) are abundant Carabidae in lowbush blueberry fields and may contribute to weed seed predation. We used laboratory no-choice test experiments to determine if these beetles feed on seeds of hair fescue (Festuca filiformis Pourr., Poales: Poaceae), poverty oatgrass (Danthonia spicata L.), and red sorrel (Rumex acetosella L., Caryophyllales: Polygonaceae), which are common weeds in lowbush blueberry (Vaccinium angustifolium Ait., Ericales: Ericaceae) fields. Poecilus lucublandus and P. mutus did not feed on seeds of the test weed species, but H. rufipes consumed on average over 30 seeds of each species. There are other weed seeds in blueberry fields that could be palatable to P. lucublandus and P. mutus, which warrants further research on the granivory potential of these important carabid species.
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temperature thresholds and growing degree day models for red sorrel Rumex acetosella ramet sprouting emergence and flowering in wild blueberry
Weed Science, 2015Co-Authors: Scott N White, Nathan S. Boyd, Rene C. Van AckerAbstract:Abstract Red sorrel is a common herbaceous creeping perennial weed in wild blueberry fields in Nova Scotia that spreads by seeds and an extensive creeping root system. Experiments were established to determine temperature thresholds for ramet sprouting from creeping root fragments and to develop growing-degree-day (GDD) models for predicting ramet emergence and flowering under field conditions in wild blueberry fields in Nova Scotia. Ramets sprouted from root fragments at temperatures as low as 1 C, with an optimum temperature for ramet sprouting around 22 C. Ramet sprouting was completely inhibited at temperatures above 35 C. Cumulative ramet emergence and flowering under field conditions were adequately explained as functions of GDD by a three-parameter power equation (R2 = 0.98) and a four-parameter logistic equation (R2 = 0.87), respectively. Ramet emergence began between 110 and 265 GDD and continued throughout the season at each site. Model prediction for the initiation of emergence was 92 GDD, ...
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demography of Rumex acetosella in lowbush blueberry vaccinium angustifolium
Weed Research, 2014Co-Authors: Scott N White, Nathan S. Boyd, R C Van AckerAbstract:Summary The demography of Rumex acetosella ramets and seedlings was monitored within and between blueberry clones over the two-year lowbush blueberry production cycle in Nova Scotia, Canada. Overwintering ramets constituted the majority (>70%) of the flowering ramet population. A small proportion of ramets emerging in May and June flowered, but no ramets emerging between July and November flowered in the year of emergence. Emergence of new ramets was season-long and ramet populations were regulated by a cycle of birth and death in each production year. Ramet populations in blueberry patches had higher growth rates and lower mortality than ramet populations in bare soil patches in the non-bearing year, resulting in large net gains to ramet populations in blueberry patches during this production year. Ramet population growth rates and mortality were similar in blueberry and bare soil patches in the bearing year and net ramet populations declined during this production year. Survival rates of overwintering and new ramets varied, but ramets from both the overwintering and monthly cohorts contributed to a distinct ramet age structure at the end of each season. Seedling survival ranged from 6 ± 6 to 51 ± 12% across sites, and no seedlings flowered in the year of emergence. Transition probabilities of ramets and seedlings were used to develop a life-cycle model of R. acetosella for the 2-year lowbush blueberry production cycle. This model has utility in developing new management strategies for R. acetosella in lowbush blueberry.
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emergence and development of red sorrel Rumex acetosella l and lowbush blueberry vaccinium angustifolium ait ramets in lowbush blueberry fields
2013Co-Authors: Scott N WhiteAbstract:Dear Atrium, please find attached my revised e-thesis submission in which I have addressed the date of submission (changed August, 2013 to December, 2013 on title page). Thank you.
Nathan S. Boyd - One of the best experts on this subject based on the ideXlab platform.
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temperature thresholds and growing degree day models for red sorrel Rumex acetosella ramet sprouting emergence and flowering in wild blueberry
Weed Science, 2015Co-Authors: Scott N White, Nathan S. Boyd, Rene C. Van AckerAbstract:Abstract Red sorrel is a common herbaceous creeping perennial weed in wild blueberry fields in Nova Scotia that spreads by seeds and an extensive creeping root system. Experiments were established to determine temperature thresholds for ramet sprouting from creeping root fragments and to develop growing-degree-day (GDD) models for predicting ramet emergence and flowering under field conditions in wild blueberry fields in Nova Scotia. Ramets sprouted from root fragments at temperatures as low as 1 C, with an optimum temperature for ramet sprouting around 22 C. Ramet sprouting was completely inhibited at temperatures above 35 C. Cumulative ramet emergence and flowering under field conditions were adequately explained as functions of GDD by a three-parameter power equation (R2 = 0.98) and a four-parameter logistic equation (R2 = 0.87), respectively. Ramet emergence began between 110 and 265 GDD and continued throughout the season at each site. Model prediction for the initiation of emergence was 92 GDD, ...
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demography of Rumex acetosella in lowbush blueberry vaccinium angustifolium
Weed Research, 2014Co-Authors: Scott N White, Nathan S. Boyd, R C Van AckerAbstract:Summary The demography of Rumex acetosella ramets and seedlings was monitored within and between blueberry clones over the two-year lowbush blueberry production cycle in Nova Scotia, Canada. Overwintering ramets constituted the majority (>70%) of the flowering ramet population. A small proportion of ramets emerging in May and June flowered, but no ramets emerging between July and November flowered in the year of emergence. Emergence of new ramets was season-long and ramet populations were regulated by a cycle of birth and death in each production year. Ramet populations in blueberry patches had higher growth rates and lower mortality than ramet populations in bare soil patches in the non-bearing year, resulting in large net gains to ramet populations in blueberry patches during this production year. Ramet population growth rates and mortality were similar in blueberry and bare soil patches in the bearing year and net ramet populations declined during this production year. Survival rates of overwintering and new ramets varied, but ramets from both the overwintering and monthly cohorts contributed to a distinct ramet age structure at the end of each season. Seedling survival ranged from 6 ± 6 to 51 ± 12% across sites, and no seedlings flowered in the year of emergence. Transition probabilities of ramets and seedlings were used to develop a life-cycle model of R. acetosella for the 2-year lowbush blueberry production cycle. This model has utility in developing new management strategies for R. acetosella in lowbush blueberry.
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Hexazinone Resistance in Red Sorrel (Rumex acetosella)
Weed Science, 2014Co-Authors: Nathan S. Boyd, Nancy Mclean, Katherine RutherfordAbstract:Abstract Biannual applications of hexazinone have been applied in many lowbush blueberry fields in Nova Scotia for more than 30 years. Persistent reliance on a single herbicide chemistry may have selected for hexazinone-resistant red sorrel. The recommended rate of hexazinone (1.92 kg ai ha−1) no longer controls red sorrel in many growing regions. Six levels of hexazinone (0, 0.48, 0.96, 1.92, 3.84, and 7.68 kg ai ha−1) were applied to red sorrel plants grown in a greenhouse from seeds collected from three commercial fields and a no blueberry area to determine if they were hexazinone resistant. Red sorrel from two sites where hexazinone had not been applied regularly died at the 0.96 kg ai ha−1 rate of hexazinone whereas red sorrel from two commercial fields survived at 7.68 kg ai ha−1. It is concluded that red sorrel is hexazinone-resistant in some wild blueberry fields. A portion of the psbA gene was sequenced and it was determined that resistant plants had a Phe to Val substitution at position 255 in t...
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The Impacts of Fertilizer and Hexazinone on Sheep Sorrel (Rumex acetosella) Growth Patterns in Lowbush Blueberry Fields
Weed Science, 2011Co-Authors: Karen J. Kennedy, Nathan S. Boyd, Vilis O. Nams, A. Randall OlsonAbstract:Abstract Sheep sorrel is an invasive, creeping perennial weed of lowbush blueberry fields that decreases yields and hinders harvest. Much of the basic phenology of sheep sorrel in blueberry fields is unknown and not documented in peer-reviewed journals. Three levels of fertilizer (0, 20, and 40 kg N ha−1) and two levels of hexazinone (0 and 1.92 kg ai ha−1) were applied to three vegetative-year blueberry fields to determine their effects on root and shoot growth, biomass allocation, and seed production of sheep sorrel plants. Hexazinone efficacy varied widely between sites, but suppressed shoot biomass, achene number and weight, and reproductive biomass, as well as the reproductive ∶ shoot biomass ratio. Fertilizer tended to increase achene number and increased sheep sorrel shoot biomass in the absence of hexazinone, but had no effect on achene weight, root biomass, or reproductive biomass. When fertilizer was applied, sheep sorrel allocated resources to sexual reproduction at the expense of vegetative gr...
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Hexazinone and Fertilizer Impacts on Sheep Sorrel (Rumex acetosella) in Wild Blueberry
Weed Science, 2010Co-Authors: Karen J. Kennedy, Nathan S. Boyd, Vilis O. NamsAbstract:Abstract Sheep sorrel is an invasive, creeping perennial weed of lowbush blueberry fields. It is one of the most prominent weeds in blueberry fields in Nova Scotia and is responsible for decreasing yields. Three levels of fertilizer (0, 20, 40 kg N ha−1) and two levels of hexazinone (0 or 1.92 kg ai ha−1) were applied to experimental plots to determine their effects on sheep sorrel density. Sprout-year hexazinone reduced sheep sorrel densities, which led to increased yields. Fertilizer increased weed density in the absence of herbicides, had no effect on density in the presence of herbicides, tended to have no impact on floral buds, and did not increase yields. Fruiting-year hexazinone decreased sheep sorrel densities in some situations, but did not result in yield increases. Nomenclature: Hexazinone, Velpar; sheep sorrel, Rumex acetosella L.; lowbush blueberry, Vaccinium angustifolium Ait. and Vaccinium myrtilloides Michx.
Luciano Gaudio - One of the best experts on this subject based on the ideXlab platform.
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effects of sulphadimethoxine on cosmopolitan weeds amaranthus retroflexus l plantago major l and Rumex acetosella l
Agriculture Ecosystems & Environment, 1997Co-Authors: Luciana Migliore, Cinzia Civitareale, Gianfranco Brambilla, Salvatore Cozzolino, Paolo Casoria, Luciano GaudioAbstract:Animal wastes from intensive farming are generally collected for field fertilisation. They may contain drugs that can become soil pollutants. The effect of such contamination on terrestrial biota has been demonstrated in laboratory tests on different plant species, using a common antimicrobial, sulphadimethoxine. In the near future, the monitoring of antimicrobial contamination in arable lands and their crops will be of importance for the protection of natural ecosystems and consumers. A possible tool for this monitoring is the use of weeds that can constitute a ‘mesh’ from which antimicrobial contamination can be detected. In laboratory tests, some direct effects of sulphadimethoxine contamination were demonstrated on normal development and growth of three cosmopolitan weed species, Amaranthus retroflexus L., Plantago major L. and Rumex acetosella L. These effects depended on the very high accumulation rates in plants (thousand μg g−1). P. major accumulated the highest amount of drug followed by A. retroflexus and R. acetosella. These data further highlight the environmental risk of sludge application on soils and the possible contamination of food nets; but also give a potential tool for the monitoring of antimicrobial soil contamination.
Vilis O. Nams - One of the best experts on this subject based on the ideXlab platform.
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Poecilus lucublandus (Coleoptera: Carabidae) and Pterostichus mutus Do Not Feed on Hair Fescue, Red Sorrel, and Poverty Oatgrass Seeds.
Journal of insect science (Online), 2019Co-Authors: Alexandre M M C Loureiro, Vilis O. Nams, G. Christopher Cutler, Scott N WhiteAbstract:Poecilus lucublandus (Say), Pterostichus mutus (Say), and Harpalus rufipes (De Geer) are abundant Carabidae in lowbush blueberry fields and may contribute to weed seed predation. We used laboratory no-choice test experiments to determine if these beetles feed on seeds of hair fescue (Festuca filiformis Pourr., Poales: Poaceae), poverty oatgrass (Danthonia spicata L.), and red sorrel (Rumex acetosella L., Caryophyllales: Polygonaceae), which are common weeds in lowbush blueberry (Vaccinium angustifolium Ait., Ericales: Ericaceae) fields. Poecilus lucublandus and P. mutus did not feed on seeds of the test weed species, but H. rufipes consumed on average over 30 seeds of each species. There are other weed seeds in blueberry fields that could be palatable to P. lucublandus and P. mutus, which warrants further research on the granivory potential of these important carabid species.
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The Impacts of Fertilizer and Hexazinone on Sheep Sorrel (Rumex acetosella) Growth Patterns in Lowbush Blueberry Fields
Weed Science, 2011Co-Authors: Karen J. Kennedy, Nathan S. Boyd, Vilis O. Nams, A. Randall OlsonAbstract:Abstract Sheep sorrel is an invasive, creeping perennial weed of lowbush blueberry fields that decreases yields and hinders harvest. Much of the basic phenology of sheep sorrel in blueberry fields is unknown and not documented in peer-reviewed journals. Three levels of fertilizer (0, 20, and 40 kg N ha−1) and two levels of hexazinone (0 and 1.92 kg ai ha−1) were applied to three vegetative-year blueberry fields to determine their effects on root and shoot growth, biomass allocation, and seed production of sheep sorrel plants. Hexazinone efficacy varied widely between sites, but suppressed shoot biomass, achene number and weight, and reproductive biomass, as well as the reproductive ∶ shoot biomass ratio. Fertilizer tended to increase achene number and increased sheep sorrel shoot biomass in the absence of hexazinone, but had no effect on achene weight, root biomass, or reproductive biomass. When fertilizer was applied, sheep sorrel allocated resources to sexual reproduction at the expense of vegetative gr...
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Hexazinone and Fertilizer Impacts on Sheep Sorrel (Rumex acetosella) in Wild Blueberry
Weed Science, 2010Co-Authors: Karen J. Kennedy, Nathan S. Boyd, Vilis O. NamsAbstract:Abstract Sheep sorrel is an invasive, creeping perennial weed of lowbush blueberry fields. It is one of the most prominent weeds in blueberry fields in Nova Scotia and is responsible for decreasing yields. Three levels of fertilizer (0, 20, 40 kg N ha−1) and two levels of hexazinone (0 or 1.92 kg ai ha−1) were applied to experimental plots to determine their effects on sheep sorrel density. Sprout-year hexazinone reduced sheep sorrel densities, which led to increased yields. Fertilizer increased weed density in the absence of herbicides, had no effect on density in the presence of herbicides, tended to have no impact on floral buds, and did not increase yields. Fruiting-year hexazinone decreased sheep sorrel densities in some situations, but did not result in yield increases. Nomenclature: Hexazinone, Velpar; sheep sorrel, Rumex acetosella L.; lowbush blueberry, Vaccinium angustifolium Ait. and Vaccinium myrtilloides Michx.
Luciana Migliore - One of the best experts on this subject based on the ideXlab platform.
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effects of sulphadimethoxine on cosmopolitan weeds amaranthus retroflexus l plantago major l and Rumex acetosella l
Agriculture Ecosystems & Environment, 1997Co-Authors: Luciana Migliore, Cinzia Civitareale, Gianfranco Brambilla, Salvatore Cozzolino, Paolo Casoria, Luciano GaudioAbstract:Animal wastes from intensive farming are generally collected for field fertilisation. They may contain drugs that can become soil pollutants. The effect of such contamination on terrestrial biota has been demonstrated in laboratory tests on different plant species, using a common antimicrobial, sulphadimethoxine. In the near future, the monitoring of antimicrobial contamination in arable lands and their crops will be of importance for the protection of natural ecosystems and consumers. A possible tool for this monitoring is the use of weeds that can constitute a ‘mesh’ from which antimicrobial contamination can be detected. In laboratory tests, some direct effects of sulphadimethoxine contamination were demonstrated on normal development and growth of three cosmopolitan weed species, Amaranthus retroflexus L., Plantago major L. and Rumex acetosella L. These effects depended on the very high accumulation rates in plants (thousand μg g−1). P. major accumulated the highest amount of drug followed by A. retroflexus and R. acetosella. These data further highlight the environmental risk of sludge application on soils and the possible contamination of food nets; but also give a potential tool for the monitoring of antimicrobial soil contamination.
