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D. A. Downie - One of the best experts on this subject based on the ideXlab platform.
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locating the sources of an invasive pest Grape phylloxera using a mitochondrial dna gene genealogy
Molecular Ecology, 2002Co-Authors: D. A. DownieAbstract:Range expansions through human introductions have increased with global commerce and have led to the extinction of Native species, alterations in community structure and pest status of the invasive species. Inferring the evolutionary history of invasive species can help to build a firmer footing for management tactics. This study used mitochondrial DNA (mtDNA) sequence comparisons of samples collected from the Native and introduced ranges of a pest herbivore of cultivated Grapes, Grape phylloxera (Daktulosphaira vitifoliae Fitch, Phylloxeridae) to infer the sources and pattern of introductions into worldwide viticulture. Introductions into viticulture from its Native North American range first occurred in the mid-19th century. The pattern of spread has suggested a focus of introduction into France, but independent introductions may have occurred elsewhere. The results show that the introduced population represents a limited subsample of the Native genetic diversity. The data suggest that most Grape phylloxera in viticulture, including all European, have originated in the northeastern USA where the Grape species Vitis riparia dominates. There was evidence for independent introductions into South Africa and California. Most California haplotypes were most closely related to Native Grape phylloxera from the Atlantic Coast on V. vulpina. It is likely that subsequent spread from California into Australia, New Zealand and Peru has occurred.
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patterns of genetic variation in Native Grape phylloxera on two sympatric host species
Molecular Ecology, 2000Co-Authors: D. A. DownieAbstract:Random amplified polymorphic DNA (RAPD) markers were used to examine population genetic structure in populations of Native Grape phylloxera. This research asked: (i) do RAPD markers distinguish two groups corresponding to the two host plant species; and (ii) do RAPD markers distinguish groups according to spatial location, independent of host plant association? Forty-nine phylloxera clones were collected from five pairs of adjacent individuals of two sympatric Grape species in five sites along a 145 km transect in Missouri, USA. A high level of polymorphism was observed, with some evidence for structuring between host plant species and no evidence for spatial structuring. An analysis of molecular variance (amova) found that 6.52% of the variance in RAPD banding patterns was attributable to host species and 7.96% of the variance was attributable to spatial location. A cluster analysis did not result in two groups corresponding to the two hosts, or to five groups corresponding to the geographical sites sampled. A Mantel test showed a low correlation between genetic similarity and spatial location. Two of the 93 RAPD markers were nonrandomly associated between the hosts. It is suggested that there may be a small host-mediated effect on genetic variation but stochastic dispersal and a highly heterogeneous environment may be the primary influences on the observed polymorphism.
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Performance of Native Grape phylloxera on host plants within and among terrestrial islands in Arizona, USA
Oecologia, 1999Co-Authors: D. A. DownieAbstract:In Arizona, USA, the canyon Grape, Vitis arizonica Englemann, and Grape phylloxera ( Daktulosphaira vitifoliae Fitch, Homoptera, Phylloxeridae) are distributed among mountain ranges that are surrounded by expanses of desert lacking Vitis habitat, thus forming a system of terrestrial islands. Both herbivore and host populations may have diverged genetically among mountain ranges under the influence of restricted gene flow and variable selection among sites. Herbivore adaptation to local hosts would be expected to ensue, with the potential to promote divergence, both in traits under selection and by further reducing the probability of interisland colonization. To test the hypothesis that phylloxera are adapted to local hosts, demographic components of fitness of field-collected Native Grape phylloxera were measured in the greenhouse on vines of V. arizonica that were categorized as either natal, neighboring, and or isolated hosts. There was no evidence for greater adaptation to natal or neighboring hosts but there were significant interactions between herbivore and host treatments in one experiment. There was genetic variation for gall formation among six clones tested. Though a failure to detect local adaptation could have resulted from low statistical power, benign experimental conditions, or inadequate genetic variation, the divergence of isolated Grape populations is suggested to have been insufficient to promote local adaptation in Grape phylloxera at the level of isolated mountain ranges. It is further suggested that, within populations, adaptation to individual host plants could be forestalled by selection for ’general purpose genotypes’ through wind-borne displacement of colonizers into the unpredictable environment of a heterogeneous array of hosts. In addition, short-term extinction/colonization dynamics could promote gene flow such that time is insufficient for adaptive mutations or gene combination to arise.
Jan H Swiegers - One of the best experts on this subject based on the ideXlab platform.
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influence of oenococcus oeni and brettanomyces bruxellensis on wine microbial taxonomic and functional potential profiles
American Journal of Enology and Viticulture, 2018Co-Authors: Marie Lisandra Zepedamendoza, Nathalia Edwards, Mikkel Gulmann Madsen, Martin Abelkistrup, Lara Puetz, Thomas Sicheritzponten, Jan H SwiegersAbstract:The interactions between lactic acid bacteria, yeast, and other wine microbiota impact on wine quality. Some strains of lactic acid bacteria Oenococcus oeni possess cinnamoyl esterase activity that releases hydroxycinnamic acids (HCAs) that can subsequently be processed by some strains of the spoilage yeast Brettanomyces bruxellensis and lead to off-flavor compounds. Using metagenomic analyses, this study investigated the influence of O. oeni and B. bruxellensis on the taxonomic and functional potential profiles of the microbial community of Cabernet Sauvignon wine, particularly regarding flavor formation. Metagenomic datasets were generated from inoculations of three strains of B. bruxellensis, in combination with two O. oeni strains, with and without cinnamoyl esterase activity. Effect on the microbial profiles was found to depend on the O. oeni and B. bruxellensis strains being combined and on the abundance that the inoculants reach in the final wine, which depends on unidentified conditions (e.g., derived from microbial interactions). This study confirmed that the potential of B. bruxellensis to produce off-flavor compounds from HCAs is strain dependent. Interestingly, the samples without microbial inoculants also had this potential, suggesting that microbiota from the Native Grape could also influence the levels of HCAs. The metagenomic analyses complemented by experimental validation also found that the presence of B. bruxellensis did not interfere with the microbial functional potential to transform l-malic acid into l-lactic acid, which typically leads to a less acidic flavor. We show that metagenomic approaches can help uncover the complex wine microbial community traits, such as flavor, impacted by the simultaneous presence of O. oeni and B. bruxellensis.
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influence of oenococcus oeni and brettanomyces bruxellensis on aged wine microbial taxonomic and functional profiles
bioRxiv, 2017Co-Authors: Marie Lisandra Zepedamendoza, Nathalia Edwards, Mikkel Gulmann Madsen, Martin Abelkistrup, Lara Puetz, Thomas Sicheritzponten, Jan H SwiegersAbstract:In the wine making process, the interactions between lactic acid bacteria (LAB), yeast and other wine microflora have an impact on the wine quality. In this study, we investigate the influence of the LAB Oenococcus oeni and the spoilage yeast Brettanomyces bruxellensis on the microbial community of a Cabernet Sauvignon wine. We generated metagenomic datasets from inoculations of three strains of B. bruxellensis, in combination with two O. oeni strains, one with and one without cinnamoyl esterase activity. This esterase activity releases hydroxycinnamic acids (HCAs) that can subsequently be processed by some B. bruxellensis strains able to generate off-flavor compounds. We evaluated the influence of the O. oeni and B. bruxellensis on the microbial taxonomic and functional potential profile, particularly regarding off-flavor formation due to HCAs. We found that the effect on the microbial profiles depends on i) the O. oeni and B. bruxellensis strains being combined and ii) the abundance they reach in the final wine, which depends on certain unidentified conditions. We confirmed that the potential of B. bruxellensis to produce off-flavor compounds from HCAs depends on the strain. Interestingly, the samples without microbial inoculants also had this potential, suggesting that Native Grape microbiota could also influence the levels of HCA. We also found that the presence of B. bruxellensis does not interfere with the malolactic fermentation of the evaluated O. oeni strains, which leads to a less acidic taste. We show that metagenomic approaches can help uncover the complex wine microbial community traits, such as flavor, impacted by the simultaneous presence of O. oeni and B. bruxellensis.
Violetka Tsolova - One of the best experts on this subject based on the ideXlab platform.
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elevated gene expression in chalcone synthase enzyme suggests an increased production of flavonoids in skin and synchronized red cell cultures of north american Native Grape berries
DNA and Cell Biology, 2012Co-Authors: Gina Davis, Anthony Ananga, Stoyanka Krastanova, Safira Sutton, Joel W Ochieng, Stephen Leong, Violetka TsolovaAbstract:Anthocyanins are antioxidants and are among the natural products synthesized via the flavonoid biosynthesis pathway. Anthocyanins have been recommended for dietary intake in the prevention of cardiovascular diseases, cancer, and age-related conditions such as Alzheimer's disease or dementia. With an increasingly aging population in many parts of the world, strategies for the commercial production of in vitro synchronized red cell cultures as natural antioxidants will be a significant contribution to human medicine. Red pigmented fruits such as Grapes (Vitis sp.) are a major source of bioavailable anthocyanins and other polyphenols. Since the level of antioxidants varies among cultivars, this study is the first one that phytochemically and genetically characterizes Native Grape cultivars of North America to determine the optimal cultivar and berry cells for the production of anthocyanins as antioxidants. Using real-time PCR and bioinformatics approaches, we tested for the transcript expression of the chalc...
M. A. Walker - One of the best experts on this subject based on the ideXlab platform.
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Population Structure, Diversity and Reproductive Mode of the Grape Phylloxera (Daktulosphaira vitifoliae) across Its Native Range.
PLOS ONE, 2017Co-Authors: Karl T. Lund, Summaira Riaz, M. A. WalkerAbstract:Grape Phylloxera, Daktulosphaira vitifoliae, is a gall-forming insect that feeds on the leaves and roots of many Vitis species. The roots of the cultivated V. vinifera cultivars and hybrids are highly susceptible to Grape phylloxera feeding damage. The Native range of this insect covers most of North America, and it is particularly abundant in the eastern and central United States. Phylloxera was introduced from North America to almost all Grape-growing regions across five of the temperate zone continents. It devastated vineyards in each of these regions causing large-scale disruptions to Grape growers, wine makers and national economies. In order to understand the population diversity of Grape phylloxera in its Native range, more than 500 samples from 19 States and 34 samples from the introduced range (northern California, Europe and South America) were genotyped with 32 simple sequence repeat markers. STRUCTURE, a model based clustering method identified five populations within these samples. The five populations were confirmed by a neighbor-joining tree and principal coordinate analysis (PCoA). These populations were distinguished by their Vitis species hosts and their geographic locations. Samples collected from California, Europe and South America traced back to phylloxera sampled in the northeastern United States on V. riparia, with some influence from phylloxera collected along the Atlantic Coast and Central Plains on V. vulpina. Reproductive statistics conclusively confirmed that sexual reproduction is common in the Native range and is combined with cyclical parthenogenesis. Native Grape phylloxera populations were identified to be under Hardy-Weinberg equilibrium. The identification of admixed samples between many of these populations indicates that shared environments facilitate sexual reproduction between different host associated populations to create new genotypes of phylloxera. This study also found that assortative mating might occur across the sympatric range of the V. vulpina west and V. cinerea populations.
Marie Lisandra Zepedamendoza - One of the best experts on this subject based on the ideXlab platform.
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influence of oenococcus oeni and brettanomyces bruxellensis on wine microbial taxonomic and functional potential profiles
American Journal of Enology and Viticulture, 2018Co-Authors: Marie Lisandra Zepedamendoza, Nathalia Edwards, Mikkel Gulmann Madsen, Martin Abelkistrup, Lara Puetz, Thomas Sicheritzponten, Jan H SwiegersAbstract:The interactions between lactic acid bacteria, yeast, and other wine microbiota impact on wine quality. Some strains of lactic acid bacteria Oenococcus oeni possess cinnamoyl esterase activity that releases hydroxycinnamic acids (HCAs) that can subsequently be processed by some strains of the spoilage yeast Brettanomyces bruxellensis and lead to off-flavor compounds. Using metagenomic analyses, this study investigated the influence of O. oeni and B. bruxellensis on the taxonomic and functional potential profiles of the microbial community of Cabernet Sauvignon wine, particularly regarding flavor formation. Metagenomic datasets were generated from inoculations of three strains of B. bruxellensis, in combination with two O. oeni strains, with and without cinnamoyl esterase activity. Effect on the microbial profiles was found to depend on the O. oeni and B. bruxellensis strains being combined and on the abundance that the inoculants reach in the final wine, which depends on unidentified conditions (e.g., derived from microbial interactions). This study confirmed that the potential of B. bruxellensis to produce off-flavor compounds from HCAs is strain dependent. Interestingly, the samples without microbial inoculants also had this potential, suggesting that microbiota from the Native Grape could also influence the levels of HCAs. The metagenomic analyses complemented by experimental validation also found that the presence of B. bruxellensis did not interfere with the microbial functional potential to transform l-malic acid into l-lactic acid, which typically leads to a less acidic flavor. We show that metagenomic approaches can help uncover the complex wine microbial community traits, such as flavor, impacted by the simultaneous presence of O. oeni and B. bruxellensis.
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influence of oenococcus oeni and brettanomyces bruxellensis on aged wine microbial taxonomic and functional profiles
bioRxiv, 2017Co-Authors: Marie Lisandra Zepedamendoza, Nathalia Edwards, Mikkel Gulmann Madsen, Martin Abelkistrup, Lara Puetz, Thomas Sicheritzponten, Jan H SwiegersAbstract:In the wine making process, the interactions between lactic acid bacteria (LAB), yeast and other wine microflora have an impact on the wine quality. In this study, we investigate the influence of the LAB Oenococcus oeni and the spoilage yeast Brettanomyces bruxellensis on the microbial community of a Cabernet Sauvignon wine. We generated metagenomic datasets from inoculations of three strains of B. bruxellensis, in combination with two O. oeni strains, one with and one without cinnamoyl esterase activity. This esterase activity releases hydroxycinnamic acids (HCAs) that can subsequently be processed by some B. bruxellensis strains able to generate off-flavor compounds. We evaluated the influence of the O. oeni and B. bruxellensis on the microbial taxonomic and functional potential profile, particularly regarding off-flavor formation due to HCAs. We found that the effect on the microbial profiles depends on i) the O. oeni and B. bruxellensis strains being combined and ii) the abundance they reach in the final wine, which depends on certain unidentified conditions. We confirmed that the potential of B. bruxellensis to produce off-flavor compounds from HCAs depends on the strain. Interestingly, the samples without microbial inoculants also had this potential, suggesting that Native Grape microbiota could also influence the levels of HCA. We also found that the presence of B. bruxellensis does not interfere with the malolactic fermentation of the evaluated O. oeni strains, which leads to a less acidic taste. We show that metagenomic approaches can help uncover the complex wine microbial community traits, such as flavor, impacted by the simultaneous presence of O. oeni and B. bruxellensis.