The Experts below are selected from a list of 216 Experts worldwide ranked by ideXlab platform
Michael J Blum - One of the best experts on this subject based on the ideXlab platform.
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Neutral and non-neutral factors shape an Emergent Plant–antagonist interaction
Evolutionary Ecology, 2018Co-Authors: Rebecca F Hazen, Kristine N Moody, Michael J BlumAbstract:Discerning the mechanisms responsible for Emergent evolutionary radiations, community assembly, and the maintenance of diversity is necessary for understanding the evolutionary ecology of species interactions in changing landscapes. These processes can be driven by stochastic (neutral) factors, such as genetic drift, or deterministic (non-neutral) factors, such as the external environment and heritable phenotypic variation. Neutral and non-neutral factors can shape species interactions, but the relative influence of these different processes on antagonistic relationships is not well understood. We leveraged the recent discovery of a novel herbivore (Caloptilia triadicae) on invasive Chinese tallow (Triadica sebifera) to investigate the nature and relative importance of different factors influencing Plant–antagonist interactions. We assessed measures of host attributes, herbivore demography and herbivory across the North American range of Triadica according to geography, environmental variation, and host genetic variation. We found that leaf toughness corresponded to genetic variation in Triadica, longitude, and mean temperature. Genetic variation in Triadica was the strongest predictor of herbivore abundance, especially for the early leaf mining stages, though herbivore abundance also corresponded to longitude. Model variables did not explain leaf damage, which was driven by interactions with late-stage larvae. Trends in herbivore demography were not consistent with previously reported geographic patterns of Triadica genetic variation related to tannin defense, but were consistent with patterns revealed by other studies of Triadica phenolic compounds and C:N, as well as low sensitivity of endophagous herbivores to tannins in the absence of parasitoids. Our findings suggest that even simple geographic mosaics of genetic and environmental variation, as well as distance-dependent dispersal, can influence the establishment and trajectory of novel species interactions.
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neutral and non neutral factors shape an Emergent Plant antagonist interaction
Evolutionary Ecology, 2018Co-Authors: Rebecca F Hazen, Kristine N Moody, Michael J BlumAbstract:Discerning the mechanisms responsible for Emergent evolutionary radiations, community assembly, and the maintenance of diversity is necessary for understanding the evolutionary ecology of species interactions in changing landscapes. These processes can be driven by stochastic (neutral) factors, such as genetic drift, or deterministic (non-neutral) factors, such as the external environment and heritable phenotypic variation. Neutral and non-neutral factors can shape species interactions, but the relative influence of these different processes on antagonistic relationships is not well understood. We leveraged the recent discovery of a novel herbivore (Caloptilia triadicae) on invasive Chinese tallow (Triadica sebifera) to investigate the nature and relative importance of different factors influencing Plant–antagonist interactions. We assessed measures of host attributes, herbivore demography and herbivory across the North American range of Triadica according to geography, environmental variation, and host genetic variation. We found that leaf toughness corresponded to genetic variation in Triadica, longitude, and mean temperature. Genetic variation in Triadica was the strongest predictor of herbivore abundance, especially for the early leaf mining stages, though herbivore abundance also corresponded to longitude. Model variables did not explain leaf damage, which was driven by interactions with late-stage larvae. Trends in herbivore demography were not consistent with previously reported geographic patterns of Triadica genetic variation related to tannin defense, but were consistent with patterns revealed by other studies of Triadica phenolic compounds and C:N, as well as low sensitivity of endophagous herbivores to tannins in the absence of parasitoids. Our findings suggest that even simple geographic mosaics of genetic and environmental variation, as well as distance-dependent dispersal, can influence the establishment and trajectory of novel species interactions.
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host genetic variation and microenvironment shape an Emergent Plant antagonist interaction
Evolutionary Ecology, 2016Co-Authors: Rebecca F Hazen, Michael J BlumAbstract:Geographic mosaics of interspecific interactions can arise as a consequence of intrinsic and extrinsic deterministic factors. In this study, we took advantage of the recent discovery of a specialist leaf-miner (Caloptilia triadicae) on invasive Chinese tallow (Triadica sebifera) in the southeastern United States to examine deterministic drivers of variation in Plant–animal antagonistic interactions. We conducted a common garden study to assess the influence of intrinsic host genetic variation and extrinsic microenvironment on Triadica traits as well as Caloptilia infestation and mortality. We found that tree size, branch leaf density, and leaf toughness differed according to multilocus estimates of genetic variation. Host genetic variation also influenced mortality of early instar Caloptilia, but had little effect on peak or late season infestation. Triadica from hyperinvasive populations were larger, exhibited reduced leaf density and tougher leaves, and had the lowest levels of peak season Caloptilia infestation, but also had the lowest levels of early instar mortality. Microhabitat variation associated with edge effects influenced tree size as well as late season infestation. These findings indicate that Caloptilia–Triadica interactions reflect seasonal shifts in the relative influence of intrinsic and extrinsic drivers, where peak season interactions largely reflect genetic variation in hosts, and late–season interactions reflect microenvironmental conditions. Further study of Caloptilia infestations could offer additional understanding of novel interactions that arise following species introductions.
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Host genetic variation and microenvironment shape an Emergent Plant–antagonist interaction
Evolutionary Ecology, 2016Co-Authors: Rebecca F Hazen, Michael J BlumAbstract:Geographic mosaics of interspecific interactions can arise as a consequence of intrinsic and extrinsic deterministic factors. In this study, we took advantage of the recent discovery of a specialist leaf-miner (Caloptilia triadicae) on invasive Chinese tallow (Triadica sebifera) in the southeastern United States to examine deterministic drivers of variation in Plant–animal antagonistic interactions. We conducted a common garden study to assess the influence of intrinsic host genetic variation and extrinsic microenvironment on Triadica traits as well as Caloptilia infestation and mortality. We found that tree size, branch leaf density, and leaf toughness differed according to multilocus estimates of genetic variation. Host genetic variation also influenced mortality of early instar Caloptilia, but had little effect on peak or late season infestation. Triadica from hyperinvasive populations were larger, exhibited reduced leaf density and tougher leaves, and had the lowest levels of peak season Caloptilia infestation, but also had the lowest levels of early instar mortality. Microhabitat variation associated with edge effects influenced tree size as well as late season infestation. These findings indicate that Caloptilia–Triadica interactions reflect seasonal shifts in the relative influence of intrinsic and extrinsic drivers, where peak season interactions largely reflect genetic variation in hosts, and late–season interactions reflect microenvironmental conditions. Further study of Caloptilia infestations could offer additional understanding of novel interactions that arise following species introductions.
Stephen M Kirkwood - One of the best experts on this subject based on the ideXlab platform.
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Emergent Plant decomposition and sedimentation response to sediments varying in texture phosphorus content and frequency of deposition
Environmental and Experimental Botany, 1998Co-Authors: Sharon M Vargo, Robert K Neely, Stephen M KirkwoodAbstract:The impact of sedimentation on the decay of Typha latifolia, Typha angustifolia and Sparganium eurycarpum litter was evaluated in two Michigan wetlands. In one wetland, T. latifolia decay was studied among replicates of three treatments (unsedimented treatment, one-time sediment application (sandy loam) and multiple sediment applications). In the second wetland, decomposition of T. angustifolia and S. eurycarpum, exposed to phosphorus-enriched clay and unenriched clay applications, was assessed in contrast to an unsedimented control treatment. A one-time application of coarse sediment was sufficient to inhibit decay of T. latifolia by about 10% over 470 days. Application of unenriched and phosphorus-enriched clay suppressed S. eurycarpum decay by about 6–8% over 117 days; however, T. angustifolia decomposition was diminished by only 2% during the same time period. Neither the net flux of nitrogen nor phosphorus mass from decaying tissues was influenced by sediment application. Averages of %N concentration in T. latifolia tissues, however, were higher under unsedimented regimes than sedimented regimes. Among measures of water quality (dissolved oxygen, NH4-N, NO3-N, total P and suspended solids concentrations), only NH4-N demonstrated a significant difference among treatments at the T. latifolia field site (0.13 mg NH4-N l−1 higher in the unsedimented treatment than the sedimented treatments).
Henry R Murkin - One of the best experts on this subject based on the ideXlab platform.
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relative importance of algae and Emergent Plant litter to freshwater marsh invertebrates
Canadian Journal of Fisheries and Aquatic Sciences, 1994Co-Authors: Suzanne Campeau, Henry R Murkin, Rodger D TitmanAbstract:We test the hypotheses that (1) algae are a major food source for marsh invertebrates and (2) Plant litter serves mainly as cover for invertebrates and a substrate for algal growth rather than as a...
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flooding and the decomposition of litter of four Emergent Plant species in a prairie wetland
Wetlands, 1991Co-Authors: Arnold G Van Der Valk, Judith M Rhymer, Henry R MurkinAbstract:Changes in mass, N, and P for old and new litter of four Emergent Plant species (Scolochloa festucacea (Willdl.) Link,Phragmites australis (Cav.) Trin ex Steud.,Typha ×glauca Godr., andScirpus lacustris L. spp.glaucus (Sm.) Hartm.) were studied under two water-level regimes in a 10-cell experimental marsh complex in the Delta Marsh, Manitoba, Canada. In the normal regime, water levels were kept at the regulated water level for Lake Manitoba until the fall of 1981, while in the flooded or high-water regime, they were raised 1 m above the regulated level in the fall of 1980. In the spring of 1980, old litter (i.e., litter from the previous growing season) was placed in all ten cells of the complex, and in the fall of 1980, new litter (i.e., litter from the 1980 growing season) was placed in the same 10 cells. Litter ofS. festucacea had the highest mean decomposition rate (k=0.00171), followed byT. ×glauca (0.0131),S.l. glaucus (0.00126), andP. australis (0.00050). Mean decomposition rates were higher in the flooded treatment than in the normal treatment forP. australis andS. festucacea. Within water-level treatments, mass loss depended on initial litter age.
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Flooding and the decomposition of litter of four Emergent Plant species in a prairie wetland
Wetlands, 1991Co-Authors: Arnold G Van Der Valk, Judith M Rhymer, Henry R MurkinAbstract:Changes in mass, N, and P for old and new litter of four Emergent Plant species ( Scolochloa festucacea (Willdl.) Link, Phragmites australis (Cav.) Trin ex Steud., Typha × glauca Godr., and Scirpus lacustris L. spp. glaucus (Sm.) Hartm.) were studied under two water-level regimes in a 10-cell experimental marsh complex in the Delta Marsh, Manitoba, Canada. In the normal regime, water levels were kept at the regulated water level for Lake Manitoba until the fall of 1981, while in the flooded or high-water regime, they were raised 1 m above the regulated level in the fall of 1980. In the spring of 1980, old litter (i.e., litter from the previous growing season) was placed in all ten cells of the complex, and in the fall of 1980, new litter (i.e., litter from the 1980 growing season) was placed in the same 10 cells. Litter of S. festucacea had the highest mean decomposition rate (k=0.00171), followed by T . × glauca (0.0131), S.l. glaucus (0.00126), and P. australis (0.00050). Mean decomposition rates were higher in the flooded treatment than in the normal treatment for P. australis and S. festucacea . Within water-level treatments, mass loss depended on initial litter age. The amount of N and P lost or gained by the end of 1981 varied with species, litter age, and water-level treatment. Scolochloa festucacea old and new litter had a lower percent N and P remaining in the flooded than in the normal water-level treatment. The percent N and P remaining in old litter of P. australis and S.l. glaucus at the end of the study was higher than that in new litter regardless of water-level treatment. For T . × glauca , however, new litter had a higher percent of N and P remaining than old litter at the end of the study in both water-level treatments. Litter with lower initial N and P levels accumulated more N and P than did that with higher initial levels.
Rebecca F Hazen - One of the best experts on this subject based on the ideXlab platform.
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Neutral and non-neutral factors shape an Emergent Plant–antagonist interaction
Evolutionary Ecology, 2018Co-Authors: Rebecca F Hazen, Kristine N Moody, Michael J BlumAbstract:Discerning the mechanisms responsible for Emergent evolutionary radiations, community assembly, and the maintenance of diversity is necessary for understanding the evolutionary ecology of species interactions in changing landscapes. These processes can be driven by stochastic (neutral) factors, such as genetic drift, or deterministic (non-neutral) factors, such as the external environment and heritable phenotypic variation. Neutral and non-neutral factors can shape species interactions, but the relative influence of these different processes on antagonistic relationships is not well understood. We leveraged the recent discovery of a novel herbivore (Caloptilia triadicae) on invasive Chinese tallow (Triadica sebifera) to investigate the nature and relative importance of different factors influencing Plant–antagonist interactions. We assessed measures of host attributes, herbivore demography and herbivory across the North American range of Triadica according to geography, environmental variation, and host genetic variation. We found that leaf toughness corresponded to genetic variation in Triadica, longitude, and mean temperature. Genetic variation in Triadica was the strongest predictor of herbivore abundance, especially for the early leaf mining stages, though herbivore abundance also corresponded to longitude. Model variables did not explain leaf damage, which was driven by interactions with late-stage larvae. Trends in herbivore demography were not consistent with previously reported geographic patterns of Triadica genetic variation related to tannin defense, but were consistent with patterns revealed by other studies of Triadica phenolic compounds and C:N, as well as low sensitivity of endophagous herbivores to tannins in the absence of parasitoids. Our findings suggest that even simple geographic mosaics of genetic and environmental variation, as well as distance-dependent dispersal, can influence the establishment and trajectory of novel species interactions.
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neutral and non neutral factors shape an Emergent Plant antagonist interaction
Evolutionary Ecology, 2018Co-Authors: Rebecca F Hazen, Kristine N Moody, Michael J BlumAbstract:Discerning the mechanisms responsible for Emergent evolutionary radiations, community assembly, and the maintenance of diversity is necessary for understanding the evolutionary ecology of species interactions in changing landscapes. These processes can be driven by stochastic (neutral) factors, such as genetic drift, or deterministic (non-neutral) factors, such as the external environment and heritable phenotypic variation. Neutral and non-neutral factors can shape species interactions, but the relative influence of these different processes on antagonistic relationships is not well understood. We leveraged the recent discovery of a novel herbivore (Caloptilia triadicae) on invasive Chinese tallow (Triadica sebifera) to investigate the nature and relative importance of different factors influencing Plant–antagonist interactions. We assessed measures of host attributes, herbivore demography and herbivory across the North American range of Triadica according to geography, environmental variation, and host genetic variation. We found that leaf toughness corresponded to genetic variation in Triadica, longitude, and mean temperature. Genetic variation in Triadica was the strongest predictor of herbivore abundance, especially for the early leaf mining stages, though herbivore abundance also corresponded to longitude. Model variables did not explain leaf damage, which was driven by interactions with late-stage larvae. Trends in herbivore demography were not consistent with previously reported geographic patterns of Triadica genetic variation related to tannin defense, but were consistent with patterns revealed by other studies of Triadica phenolic compounds and C:N, as well as low sensitivity of endophagous herbivores to tannins in the absence of parasitoids. Our findings suggest that even simple geographic mosaics of genetic and environmental variation, as well as distance-dependent dispersal, can influence the establishment and trajectory of novel species interactions.
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host genetic variation and microenvironment shape an Emergent Plant antagonist interaction
Evolutionary Ecology, 2016Co-Authors: Rebecca F Hazen, Michael J BlumAbstract:Geographic mosaics of interspecific interactions can arise as a consequence of intrinsic and extrinsic deterministic factors. In this study, we took advantage of the recent discovery of a specialist leaf-miner (Caloptilia triadicae) on invasive Chinese tallow (Triadica sebifera) in the southeastern United States to examine deterministic drivers of variation in Plant–animal antagonistic interactions. We conducted a common garden study to assess the influence of intrinsic host genetic variation and extrinsic microenvironment on Triadica traits as well as Caloptilia infestation and mortality. We found that tree size, branch leaf density, and leaf toughness differed according to multilocus estimates of genetic variation. Host genetic variation also influenced mortality of early instar Caloptilia, but had little effect on peak or late season infestation. Triadica from hyperinvasive populations were larger, exhibited reduced leaf density and tougher leaves, and had the lowest levels of peak season Caloptilia infestation, but also had the lowest levels of early instar mortality. Microhabitat variation associated with edge effects influenced tree size as well as late season infestation. These findings indicate that Caloptilia–Triadica interactions reflect seasonal shifts in the relative influence of intrinsic and extrinsic drivers, where peak season interactions largely reflect genetic variation in hosts, and late–season interactions reflect microenvironmental conditions. Further study of Caloptilia infestations could offer additional understanding of novel interactions that arise following species introductions.
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Host genetic variation and microenvironment shape an Emergent Plant–antagonist interaction
Evolutionary Ecology, 2016Co-Authors: Rebecca F Hazen, Michael J BlumAbstract:Geographic mosaics of interspecific interactions can arise as a consequence of intrinsic and extrinsic deterministic factors. In this study, we took advantage of the recent discovery of a specialist leaf-miner (Caloptilia triadicae) on invasive Chinese tallow (Triadica sebifera) in the southeastern United States to examine deterministic drivers of variation in Plant–animal antagonistic interactions. We conducted a common garden study to assess the influence of intrinsic host genetic variation and extrinsic microenvironment on Triadica traits as well as Caloptilia infestation and mortality. We found that tree size, branch leaf density, and leaf toughness differed according to multilocus estimates of genetic variation. Host genetic variation also influenced mortality of early instar Caloptilia, but had little effect on peak or late season infestation. Triadica from hyperinvasive populations were larger, exhibited reduced leaf density and tougher leaves, and had the lowest levels of peak season Caloptilia infestation, but also had the lowest levels of early instar mortality. Microhabitat variation associated with edge effects influenced tree size as well as late season infestation. These findings indicate that Caloptilia–Triadica interactions reflect seasonal shifts in the relative influence of intrinsic and extrinsic drivers, where peak season interactions largely reflect genetic variation in hosts, and late–season interactions reflect microenvironmental conditions. Further study of Caloptilia infestations could offer additional understanding of novel interactions that arise following species introductions.
Keith L Perry - One of the best experts on this subject based on the ideXlab platform.
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genotyping of cucumber mosaic virus isolates in western new york state during epidemic years characterization of an Emergent Plant virus population
Virus Research, 2015Co-Authors: Jeremy R Thompson, Jamie L Langenhan, Marc Fuchs, Keith L PerryAbstract:In the early 2000s an epidemic of cucumber mosaic virus (CMV) spread within the Midwestern and Eastern US affecting snap and dry bean (Phaseolus vulgaris L.) cultivation. Fifty one CMV isolates from this period were partially characterized from varied hosts by sequencing a section from each of the three genomic RNAs. Aside from one subgroup II strain from pepper, all isolates, including those from snap bean, fell within the IA subgroup. The nucleotide sequence diversity of virus populations sampled at multiple sites and at different years was significantly higher than that of a population from single site in a single year, although in general the number of polymorphisms was low (<11%). Complementary DNA (cDNA) clones of Bn57, a representative isolate from snap bean, were engineered for the production of infectious in vitro RNA transcripts initiated from a T7 promoter. Infections from these cDNAs resulted in symptoms consistent with those of the original field isolate, indicating that a satellite RNA is not involved in symptom expression in snap bean. These infectious clones were used to assess symptom determinants and the effects of virus infection on Plant growth. Inoculations with pseudorecombinants derived from Bn57 and the non-bean infecting strain Fny confirmed RNA2 as a specific determinant for snap bean infection. Bn57, along with almost all isolates identified in this study contained the Y631 locus in the 2a protein, a determinant for systemic infection in bean. The presence of this locus extended to all non-bean hosts except two pepper infecting isolates. Infection by Bn57 in snap bean had a significant effect on pod number and mass with a 55 and 41 percent reduction in greenhouse assays, respectively. To our knowledge Bn57 is the first CMV strain isolated from P. vulgaris to be fully sequenced and cloned, providing a useful tool for analyses of CMV-host interactions.