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Francis A Drummond - One of the best experts on this subject based on the ideXlab platform.
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pollen mediated gene flow in managed fields of Lowbush Blueberry
Canadian Journal of Plant Science, 2020Co-Authors: Lisa J Rowland, Elizabeth L Ogden, Daniel Belld J J Bell, Francis A DrummondAbstract:Pollen-mediated gene flow was analyzed in two managed fields of Lowbush Blueberry (Vaccinium angustifolium Ait.) in Maine. Seedlings derived from open-pollinated crosses of two mother plants, one f...
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Genetic Diversity of Lowbush Blueberry throughout its U.S. Native Range in Managed and Non-managed Populations
2019Co-Authors: Lee Beers, Jeannie Rowland, Francis A DrummondAbstract:Expressed sequenced tagged-polymerase chain reaction (EST-PCR) molecular markers were used to evaluate the genetic diversity of Lowbush Blueberry across its geographic range and to compare genetic diversity among four paired managed/non-managed populations. Seventeen Lowbush Blueberry populations were sampled in a general north south transect throughout eastern United States with distances between 27 km to 1600 km separating populations. Results show that the majority of genetic variation is found within populations (75%) versus among populations (25%), and that each population was genetically unique (P ≤ 0.0001) with the exception of the Jonesboro, ME and Lubec, ME populations that were found not to be significantly different (P = 0.228). The effects of management for commercial fruit harvesting on genetic diversity were investigated in four locations in Maine with paired managed and non-managed populations. Significant differences were found between the populations indicating that commercial management influences the genetic diversity of Lowbush blueberries in the landscape, despite the fact that planting does not occur; forests are harvested and the existing understory Blueberry plants are what become established.
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a natural history of change in native bees associated with Lowbush Blueberry in maine
Northeastern Naturalist, 2017Co-Authors: Francis A Drummond, Alison C Dibble, C S Stubbs, Sara L Bushmann, John S Ascher, Jennifer RyanAbstract:More than 120 native bee species have been documented in Maine since 1930 in association with the native plant Vaccinium angustifolium (Lowbush Blueberry). We report 3 studies in commercial Lowbush Blueberry fields: (1) a survey of diversity in Osmia (mason bees) and closely related Megachile (leaf-cutter bees) using trap nests in 93 fields from 1990 to 2012, (2) a 29-year study of a native bee community, and (3) an examination of climate-change effects on bee-foraging periods during Blueberry bloom. Osmia appeared to be more stable over a 22- year period in their species richness and relative abundances in Lowbush Blueberry fields when compared to Megachile over a similar 17-year period. The native bee community in a single location in Winterport was observed to fluctuate in abundance 2 to 3 times annually. Modeling of the total bee community and taxa-specific group abundances (Bombus, Megachilids, Andrenids, and Halictids and other bees) suggest that while stochastic density-independent processes such as weather can play a role in determining their annual oscillations, density-dependent lags of 1 and 2 years appear to be the main driving forces. Estimation of fruit set over the same 29-year period, based upon native bee abundance, suggests that pollination is more buffered than community bee abundance, resulting in a lesser degree of fluctuation over time. We speculate that this finding is due to redundancy in floral preferences, multiple floral visitations, and differing pollination efficiencies by the highly diverse native bee community associated with Lowbush Blueberry. Effects of climate change in Maine Lowbush Blueberry fields during May bloom was investigated using a historic weather database. Since the early 1990s, precipitation has, to a large degree, reduced the number of optimal bee foraging days during bloom, with implications for pollination and bee species abundances. This new information reinforces the need for provision of pollinator gardens to support native pollinators of Lowbush Blueberry.
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grid set match an agent based simulation model predicts fruit set for the Lowbush Blueberry vaccinium angustifolium agroecosystem
Ecological Modelling, 2017Co-Authors: Alex W Bajcz, David E Hiebeler, Francis A DrummondAbstract:Abstract Fruit set, the proportion of flowers whose ovaries successfully bear fruit, is the product of dozens of processes, many of which are difficult to study and manipulate in situ . To establish which of these processes are most important in the Lowbush Blueberry ( Vaccinium angustifolium Aiton; Ericaceae) agroecosystem, an agent-based simulation model, Grid-Set-Match , with temporal and spatial elements was constructed using the R software package. Pollination ecology data from this system were used to parameterize the model. Then, results from 1,000 iterations of the model were compared to field fruit set data from a survey of 162 Lowbush Blueberry fields from 1993 to 2015 as well as from a field study conducted from 2013 to 2015. Predicted fruit set for an average Lowbush Blueberry field was 0.366 according to Grid-Set-Match . Based on currently available field data, this estimate appears realistic, although it may be a slight underestimate in part because variability in pollinator densities between real fields is higher than the model accounted for. A multiple regression model indicated that, across a sample of clones created by Grid-Set-Match under default parameter settings, fruit set declined significantly as the average genetic load of a clone’s neighbors increased and as self-pollination rate increased, with the latter effect being ∼20% stronger than the former. As such, future research should be directed towards understanding and better managing factors that may influence rates of self- vs. cross-pollination in this system, such as pollen carryover, intra-hive pollen transfer, and pollinator flight distances between consecutively visited flowers.
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abundance and diversity of wild bees hymenoptera apoidea found in Lowbush Blueberry growing regions of downeast maine
Environmental Entomology, 2015Co-Authors: Sara L Bushmann, Francis A DrummondAbstract:ABSTRACT Insect-mediated pollination is critical for Lowbush Blueberry (Ericaceae: Vaccinium angustifolium Aiton) fruit development. Past research shows a persistent presence of wild bees (Hymenoptera: Apoidea) providing pollination services even when commercial pollinators are present. We undertook the study to 1) provide a description of bee communities found in Lowbush Blueberry-growing regions, 2) identify field characteristics or farm management practices that influence those communities, 3) identify key wild bee pollinators that provide pollination services for the Blueberry crop, and 4) identify non-crop plants found within the cropping system that provide forage for wild bees. During a 4-year period, we collected solitary and eusocial bees in over 40 fields during and after Blueberry bloom, determining a management description for each field. We collected 4,474 solitary bees representing 124 species and 1,315 summer bumble bees representing nine species. No bumble bee species were previously unkno...
Christopher G Cutler - One of the best experts on this subject based on the ideXlab platform.
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short term dispersal and long term spatial and temporal patterns of carabidae coleoptera in Lowbush Blueberry fields
Environmental Entomology, 2020Co-Authors: Scott N White, Vilis O Nams, Alexandre M M C Loureiro, Christopher G CutlerAbstract:: Carabidae (Coleoptera) are important natural enemies of many insect pests in various cropping systems. Their population dynamics and how they disperse determine how effective they are at carrying out the natural enemy function. There are robust patterns of community dynamics in annual cropping systems, but it is unclear if these would carry over into a relatively underexplored North American perennial crop. In Nova Scotia Lowbush Blueberry fields, we found that Carabidae diversity did not change with distance from field edge nor with time. Their activity density also did not change with time, but it did change with distance from field edge. We also found that the most abundant carabid of Lowbush Blueberry, Harpalus rufipes (De Geer) (Coleoptera: Carabidae), can disperse approximately 14.5 m/d. Our results shed more light on the community dynamics of Carabidae in Lowbush Blueberry fields and can help growers make informed decisions when it comes to incorporating natural enemies into their pest management practices.
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weed seed granivory by carabid beetles and crickets for biological control of weeds in commercial Lowbush Blueberry fields
Agricultural and Forest Entomology, 2016Co-Authors: Christopher G Cutler, Tess Astatkie, G S ChahilAbstract:Weeds are one of the most limiting factors in the commercial production of Lowbush blueberries Vaccinium angustifolium (Ericaceae). Sheep sorrel (Rumex acetosella) and hairy fescue (Festuca tenuifolia) are prominent weeds in Lowbush Blueberry fields. Because the granivorous insects Harpalus rufipes (Carabidae) and Gryllus pennsylvanicus (Gryllidae) are common in Lowbush Blueberry fields when sheep sorrel and hairy fescue are dispersing seeds, we examined how granivorous insects can contribute to the biocontrol of these weeds. In the laboratory, H. rufipes and G. pennsylvanicus consumed a significant number of seeds of sheep sorrel and hairy fescue, and a field experiment found that insects probably consume a significant number of sheep sorrel and hairy fescue seeds in Blueberry fields. Additional experiments found that H. rufipes was highly susceptible to field rates of phosmet and acetamiprid, although not to field rates of spirotetramat, which are insecticides that may be used in Blueberry fields when the beetle is active. Natural populations of granivorous insects probably provide a valuable ecological service in commercial Lowbush Blueberry fields and should be conserved in the development of integrated weed management programmes.
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red sorrel management and potential effect of red sorrel pollen on botrytis cinerea spore germination and infection of Lowbush Blueberry vaccinium angustifolium ait flowers
Canadian Journal of Plant Science, 2016Co-Authors: Angela Hughes, P. D. Hildebrand, Scott N White, Nathan S Boyd, Christopher G CutlerAbstract:Red sorrel is a common weed in Lowbush Blueberry fields in Nova Scotia, Canada. Grower experience suggests that high red sorrel density necessitates fungicide applications to control Botrytis cinerea, a major fungal pathogen in Lowbush Blueberry. Specific interactions between red sorrel, Lowbush Blueberry, and B. cinerea, however, remain unclear. Experiments were conducted in Nova Scotia to determine the (1) presence or absence of red sorrel pollen on Lowbush Blueberry flowers in the field, (2) impact of red sorrel pollen on in vitro B. cinerea spore germination and infection of immature and mature Blueberry flowers, and (3) effect of pronamide applications on red sorrel and Lowbush Blueberry growth. Red sorrel pollen grains were found on Blueberry flowers in the field. In vitro B. cinerea spore germination increased with increasing red sorrel pollen concentration, with the relationship adequately explained by a 3-parameter exponential rise to a maximum equation. Red sorrel pollen increased B. cinerea dis...
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wild bee pollinator communities of Lowbush Blueberry fields spatial and temporal trends
Basic and Applied Ecology, 2015Co-Authors: Christopher G Cutler, Vilis O Nams, Pamela Craig, Jason M Sproule, Cory S SheffieldAbstract:Abstract Pollination by bees (Apoidea) is a critical component of Lowbush Blueberry ( Vaccinium angustifolium Ation: Ericaceae) production. Though most Blueberry growers in eastern Canada use managed bees in Lowbush Blueberry pollination, native pollinators are recognized as an important component of the pollination service provision. In this study we examined the diversity and abundance of native bees in Lowbush Blueberry fields in Nova Scotia, while considering spatial and temporal patterns in their distribution over the growing season. In total, we collected 95 species representing 13 genera, of which Lasioglossum and Andrena comprised >92% of all individuals. The abundance of several of the most common species was inversely related to distance from the forest edge, but was low inside the adjacent forest. In contrast, species diversity was highest inside the forest and consistently low within fields. Larger bees were found further into fields than smaller bees. Whereas some abundant bees were collected most often outside the Blueberry bloom period, Lasioglossum cressonii , the most abundant species, was collected often during Blueberry bloom, suggesting it could be an effective pollinator in this system. The results highlight wild bee taxa that could be targeted for conservation efforts to potentially decrease reliance on managed pollinators.
Scott N White - One of the best experts on this subject based on the ideXlab platform.
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short term dispersal and long term spatial and temporal patterns of carabidae coleoptera in Lowbush Blueberry fields
Environmental Entomology, 2020Co-Authors: Scott N White, Vilis O Nams, Alexandre M M C Loureiro, Christopher G CutlerAbstract:: Carabidae (Coleoptera) are important natural enemies of many insect pests in various cropping systems. Their population dynamics and how they disperse determine how effective they are at carrying out the natural enemy function. There are robust patterns of community dynamics in annual cropping systems, but it is unclear if these would carry over into a relatively underexplored North American perennial crop. In Nova Scotia Lowbush Blueberry fields, we found that Carabidae diversity did not change with distance from field edge nor with time. Their activity density also did not change with time, but it did change with distance from field edge. We also found that the most abundant carabid of Lowbush Blueberry, Harpalus rufipes (De Geer) (Coleoptera: Carabidae), can disperse approximately 14.5 m/d. Our results shed more light on the community dynamics of Carabidae in Lowbush Blueberry fields and can help growers make informed decisions when it comes to incorporating natural enemies into their pest management practices.
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Evaluation of herbicides for hair fescue (Festuca filiformis) management and potential seedbank reduction in Lowbush Blueberry
Weed Technology, 2019Co-Authors: Scott N WhiteAbstract:AbstractHair fescue is a widespread, seed-limited perennial grass in Lowbush Blueberry fields. Growers rely on pronamide, an expensive and difficult herbicide to use, for hair fescue management. Recent herbicide registrations provide opportunity to reduce pronamide use, though effects of these herbicides on hair fescue suppression and seedbank reduction are not well understood. The objectives of this research were to determine (1) the effects of herbicides currently registered in Lowbush Blueberry on suppression of hair fescue tufts and (2) whether suppression of hair fescue with these herbicides reduces hair fescue seedbanks. Pronamide gave the most consistent reductions in flowering tuft density, though applications after both autumn pruning and autumn of the nonbearing year were required to reduce the hair fescue seedbank by >60% across sites. Nonbearing-year hexazinone applications did not control hair fescue or reduce the seedbank. Nonbearing-year terbacil applications reduced flowering tuft density, but hair fescue recovered in the bearing year, and the seedbank was not reduced. Glufosinate applications following autumn pruning or in the spring of the nonbearing year did not suppress hair fescue or reduce the seedbank. Spring nonbearing-year foramsulfuron applications, alone or after autumn or spring glufosinate applications, reduced hair fescue flowering tuft density, but hair fescue recovered in the bearing year, and the seedbank was not reduced. In contrast, autumn and spring glufosinate applications followed by spring nonbearing-year foramsulfuron applications, when combined with autumn nonbearing-year pronamide applications, reduced flowering tuft density in both the nonbearing and bearing years and reduced the hair fescue seedbank by 58% to 83% across sites. Results indicate that hair fescue seedbanks can be reduced in Lowbush Blueberry fields and that a reduction in pronamide use will require alternative bearing-year treatments to prevent tuft recovery and seed production.
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evaluation of herbicides for hair fescue festuca filiformis management and potential seedbank reduction in Lowbush Blueberry
Weed Technology, 2019Co-Authors: Scott N WhiteAbstract:Hair fescue is a widespread, seed-limited perennial grass in Lowbush Blueberry fields. Growers rely on pronamide, an expensive and difficult herbicide to use, for hair fescue management. Recent herbicide registrations provide opportunity to reduce pronamide use, though effects of these herbicides on hair fescue suppression and seedbank reduction are not well understood. The objectives of this research were to determine (1) the effects of herbicides currently registered in Lowbush Blueberry on suppression of hair fescue tufts and (2) whether suppression of hair fescue with these herbicides reduces hair fescue seedbanks. Pronamide gave the most consistent reductions in flowering tuft density, though applications after both autumn pruning and autumn of the nonbearing year were required to reduce the hair fescue seedbank by >60% across sites. Nonbearing-year hexazinone applications did not control hair fescue or reduce the seedbank. Nonbearing-year terbacil applications reduced flowering tuft density, but hair fescue recovered in the bearing year, and the seedbank was not reduced. Glufosinate applications following autumn pruning or in the spring of the nonbearing year did not suppress hair fescue or reduce the seedbank. Spring nonbearing-year foramsulfuron applications, alone or after autumn or spring glufosinate applications, reduced hair fescue flowering tuft density, but hair fescue recovered in the bearing year, and the seedbank was not reduced. In contrast, autumn and spring glufosinate applications followed by spring nonbearing-year foramsulfuron applications, when combined with autumn nonbearing-year pronamide applications, reduced flowering tuft density in both the nonbearing and bearing years and reduced the hair fescue seedbank by 58% to 83% across sites. Results indicate that hair fescue seedbanks can be reduced in Lowbush Blueberry fields and that a reduction in pronamide use will require alternative bearing-year treatments to prevent tuft recovery and seed production.Nomenclature: Foramsulfuron; glufosinate; hexazinone; pronamide; terbacil; hair fescue; Festuca filiformis Pourr; FESTE; Lowbush Blueberry; Vaccinium angustifolium Ait
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red sorrel management and potential effect of red sorrel pollen on botrytis cinerea spore germination and infection of Lowbush Blueberry vaccinium angustifolium ait flowers
Canadian Journal of Plant Science, 2016Co-Authors: Angela Hughes, P. D. Hildebrand, Scott N White, Nathan S Boyd, Christopher G CutlerAbstract:Red sorrel is a common weed in Lowbush Blueberry fields in Nova Scotia, Canada. Grower experience suggests that high red sorrel density necessitates fungicide applications to control Botrytis cinerea, a major fungal pathogen in Lowbush Blueberry. Specific interactions between red sorrel, Lowbush Blueberry, and B. cinerea, however, remain unclear. Experiments were conducted in Nova Scotia to determine the (1) presence or absence of red sorrel pollen on Lowbush Blueberry flowers in the field, (2) impact of red sorrel pollen on in vitro B. cinerea spore germination and infection of immature and mature Blueberry flowers, and (3) effect of pronamide applications on red sorrel and Lowbush Blueberry growth. Red sorrel pollen grains were found on Blueberry flowers in the field. In vitro B. cinerea spore germination increased with increasing red sorrel pollen concentration, with the relationship adequately explained by a 3-parameter exponential rise to a maximum equation. Red sorrel pollen increased B. cinerea dis...
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effect of dry heat direct flame and straw burning on seed germination of weed species found in Lowbush Blueberry fields
Weed Technology, 2016Co-Authors: Scott N White, Nathan S BoydAbstract:Experiments were conducted to determine the effects of dry heat, direct flame, and straw burning on germination of several weed species from Lowbush Blueberry fields. Dry heat experiments were designed as factorial arrangements of temperature (100, 200, and 300 C in experiment 1 and room temperature, 100, 200, and 300 C in experiment 2) and exposure time (0, 5, 10, 20, 40, and 80 s in experiment 1 and 2, 5, 10, and 20 s in experiment 2) to determine the exposure time required to reduce germination for each temperature. Susceptibility to dry heat varied across species tested, but germination of spreading dogbane, meadow salsify, fireweed, and hair fescue seeds collected from Lowbush Blueberry fields in Nova Scotia, Canada generally declined exponentially as a function of duration of heat exposure at the temperatures tested. Germination decreased more rapidly at higher temperatures in all species, although the duration of heat exposure required to reduce germination by 50 and 90% varied across temperatures ...
Cory S Sheffield - One of the best experts on this subject based on the ideXlab platform.
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wild bee pollinator communities of Lowbush Blueberry fields spatial and temporal trends
Basic and Applied Ecology, 2015Co-Authors: Christopher G Cutler, Vilis O Nams, Pamela Craig, Jason M Sproule, Cory S SheffieldAbstract:Abstract Pollination by bees (Apoidea) is a critical component of Lowbush Blueberry ( Vaccinium angustifolium Ation: Ericaceae) production. Though most Blueberry growers in eastern Canada use managed bees in Lowbush Blueberry pollination, native pollinators are recognized as an important component of the pollination service provision. In this study we examined the diversity and abundance of native bees in Lowbush Blueberry fields in Nova Scotia, while considering spatial and temporal patterns in their distribution over the growing season. In total, we collected 95 species representing 13 genera, of which Lasioglossum and Andrena comprised >92% of all individuals. The abundance of several of the most common species was inversely related to distance from the forest edge, but was low inside the adjacent forest. In contrast, species diversity was highest inside the forest and consistently low within fields. Larger bees were found further into fields than smaller bees. Whereas some abundant bees were collected most often outside the Blueberry bloom period, Lasioglossum cressonii , the most abundant species, was collected often during Blueberry bloom, suggesting it could be an effective pollinator in this system. The results highlight wild bee taxa that could be targeted for conservation efforts to potentially decrease reliance on managed pollinators.
G. C. Cutler - One of the best experts on this subject based on the ideXlab platform.
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High rates of parasitism of Blueberry spanworm (Lepidoptera: Geometridae) by Ichneumonidae and Tachinidae in commercial Lowbush Blueberry fields
Journal of Pest Science, 2015Co-Authors: G. C. Cutler, T. D. Gariepy, E. C. A. Silva, N. K. HillierAbstract:Blueberry spanworm, Itame ( Macaria ) argillacearia Packard, is an important defoliator of Lowbush Blueberry ( Vaccinium angustifolium Aiton), a major crop in eastern Canada. In the summer of 2012, we collected a large number of Blueberry spanworm larvae from two managed Blueberry fields in Colchester Co., Nova Scotia. Approximately 50–60 % of the field-collected larvae maintained in the laboratory were parasitized and killed. Identifications of parasitoids were based on morphological characters and mitochondrial cytochrome oxidase I sequencing. The majority of parasitism was by Phryxe pecosensis (Diptera: Tachinidae), and a wasp suspected to be a new species of Tranosemella or Tranosema (Hymenoptera: Ichneumonidae). Our results demonstrate that parasitism of Blueberry spanworm can be high in Lowbush Blueberry and that conservation or augmentative biological control should be considered in future development of management programs for this pest.
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Potential of bumble bees as bio-vectors of Clonostachys rosea for Botrytis blight management in Lowbush Blueberry
Journal of Pest Science, 2014Co-Authors: K. W. Reeh, N. Kirk Hillier, G. C. CutlerAbstract:The effectiveness of bees as vectors for microbial biological control agents has been demonstrated in greenhouses and some small-acreage crops. Less is known about the viability of this tactic for other cropping systems, or the effects of outfitting hives with dispensers on the bees. Experiments conducted in Lowbush Blueberry (Vaccinium angustifolium) fields indicated that home-made wooden, Koppert, and Enviroquest dispensers had no significant effects on foraging behavior or pollen loads of the bumble bee Bombus impatiens, but the presence of a dispenser did reduce the rate of workers exiting hives. Following exit of bees from dispensers, no difference was found in the quantity of the microbial agent Clonostachys rosea applied to the bees or blossoms, and distribution of product in the field was not influenced by dispenser design or distance from hives. However, the prevalence of the pathogen Botrytis cinerea in blossoms from cages that contained hives with dispensers with C. rosea was significantly less (10–20 %) than blossom infection in control plots, despite unseasonably inclement conditions and restricted foraging. These results suggest that C. rosea can be effectively delivered by commercial bumble bees for prevention of B. cinerea infection in V. angustifolium, but the efficacy of the technique will be limited during periods of poor weather that often occur in regions where Lowbush blueberries are grown. Some technical issues with dispensers and commercial B. impatiens hives also need to be addressed before widespread use can be expected within commercial Lowbush Blueberry production.
