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Yinghua Huang - One of the best experts on this subject based on the ideXlab platform.
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bidirectional introgression between Pinus taeda and Pinus echinata evidence from morphological and molecular data
Canadian Journal of Forest Research, 2004Co-Authors: Jiwang Chen, C G Tauer, Yinghua Huang, Guihua Bai, M E Payton, A G HolleyAbstract:The frequency of mature hybrids, including post-F1 individuals, between loblolly (Pinus taeda L.) and shortleaf pine (Pinus echinata Mill.), detectable with a codominant nuclear marker, was studied in a sympatric population from central Arkansas. The direction of introgression was also examined. The marker revealed 10 putative hybrids from the 80 trees sampled. PCR-RFLP analysis of their rbcL gene showed two of the putative hybrids (HL) share loblolly pine chloroplast DNA, and eight (HS) share the shortleaf pine chloroplast DNA. The two putative HL hybrids were morphologically similar to loblolly pine, and the eight putative HS hybrids were morphologically similar to shortleaf pine. Utilizing microsatellite data, Nei's measure of genetic identity showed the putative HL hybrids to be similar to loblolly pine, and the putative HS hybrids as being similar to shortleaf pine. An inferred tree of the individuals, using simple sequence repeat data and the neighbor-joining method, also suggested that some of the ...
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paternal chloroplast inheritance patterns in pine hybrids detected with trnl trnf intergenic region polymorphism
Theoretical and Applied Genetics, 2002Co-Authors: Jiwang Chen, C G Tauer, Yinghua HuangAbstract:The inheritance patterns of the chloroplast genomes of shortleaf pine (Pinus echinata Mill.), loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) were investigated through the trnL–trnF intergenic spacer polymorphism analysis. The DNA sequences of this spacer differ among these three closely related Pinus species. A modified 'cold' PCR-SSCP (single-strand conformation polymorphism) analysis of this spacer shows that the artificial hybrids (F1) from the shortleaf pine (seed parent) × loblolly pine (pollen parent) cross, exhibit the loblolly pine profile. Additionally, nine putative hybrids between shortleaf pine and loblolly pine, previously identified by the IDH (Isocitrate dehydrogenase) allozyme marker, presented the shortleaf pine profile indicating that shortleaf pine, not loblolly pine, sired all of the putative hybrids. Nondenatured polyacrylamide-gel electrophoresis of the trnL–trnF intergenic spacer demonstrated that the artificial hybrids (F1) from the cross, slash pine (seed parent) × shortleaf pine (pollen parent), present the shortleaf pine profile. Those results confirmed that the chloroplast genome is paternally inherited in these three species of the genus Pinus. The significance of the trnL–trnF intergenic region polymorphism and our modified 'cold' SSCP protocol for population genetic studies is discussed.
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nucleotide sequences of the internal transcribed spacers and 5 8s region of nuclear ribosomal dna in Pinus taeda l and Pinus echinata mill
Dna Sequence, 2002Co-Authors: Jiwang Chen, C G Tauer, Yinghua HuangAbstract:The 615-bp nucleotide sequences of the first partial internal transcribed spacer (ITS-1), 5.8S rDNA and ITS-2 region from Pinus taeda L. (loblolly pine) and Pinus echinata Mill. (shortleaf pine) are reported. The two pine species show the same nucleotide sequences in this region, which indicates their close phylogenetic relationship. However, our reported nucleotide sequence in this region from shortleaf pine is different from the previous report for shortleaf pine in GenBank (accession number: AF037016). Our PCR-RFLP analysis of this region confirms our sequencing data. This correction is important for pine phylogenetic studies because it is located in the conserved 5.8S rDNA region.
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regeneration methods affect genetic variation and structure in shortleaf pine Pinus echinata mill
Forest Genetics 5(3):171-178 1998, 1998Co-Authors: R G Raja, C G Tauer, R F Wittwer, Yinghua HuangAbstract:The effects of regeneration methods on genetic diversity and structure in shortleaf pine (Pinrrs echinafu >lill.) were examined by quantifying the changes in genetic composition of shortleaf pine stands following harvest by monitoring changes in allele number and frequency at heterozygous loci over time. The results were also compared to the genetic composition ofseed used for artificial regeneration following clear-cutting. Both natural regeneration treatments resulted in higher genetic variation in post-treatment seed, indicating a richer pollen cloud after management. Artificial regeneration showed fewer alleles per locus and fewer polymorphic loci compared to both natural regeneration treatments. Frequency of alternate alleles increased at 13 loci in the seedtree stand after treatment, which is an indication of less inbreeding or consanguineous mating. Single tree selection resulted in an increase in alternate allele frequencies at 9 loci and at 1 loci alternate allele frequencies decreased, indicating that the treatment may result in more inbreeding than seed tree. Artificial regeneration showed a considerable increase in alternate allele frequencies at 16 loci and hence can be considered outbred. The above mentioned observations were confirmed by comparing H,and F values for the two stands before and after treatment. The seed tree method resulted in a decrease in inbreeding, whereas the first selection cut for single tree selection did not alter it. Artificial regeneration showed a negative F value indicative of high levels of heterozygosity and outbreeding. The natural regeneration treatments did not result in genetic drift whereas the artificial regeneration showed considerable change in the genetic composition of the potential regeneration.
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segregation and linkage relationships of isoenzymes in shortleaf pine Pinus echinata mill
Theoretical and Applied Genetics, 1997Co-Authors: R G Raja, C G Tauer, R F Wittwer, Yinghua HuangAbstract:Segregation and linkage relationships were analyzed between 28 isoenzyme loci in ten natural stands representing much of the natural range of Pinus echinata Mill. (shortleaf pine). A total of 203 possible two-locus combinations were tested. Three linkage groups were revealed in this study at a linkLOD of 4.0. The first linkage group (A) consisted of Pgi and Adh-1; Gdh, Idh, Skdh-2, G6pd-2 and Aco were mapped to the second linkage group (B); the third group (C) had 2 loci: Mdh-2 and Mdh-3. A moderate linkage between Mnr-2 and Dia-2 and weak linkages between Mnr-1 and Dia-1, and Got-2 and 6pgd-2 were also detected. The significance of these results in shortleaf pine is discussed and compared to linkage maps previously reported in other conifers, including pines.
C. Dana Nelson - One of the best experts on this subject based on the ideXlab platform.
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The genetics of shortleaf pine (Pinus echinata mill.) with implications for restoration and management
Tree Genetics & Genomes, 2016Co-Authors: John F Stewart, Rodney E Will, Barbara S. Crane, C. Dana NelsonAbstract:Shortleaf pine ( Pinus echinata Mill.) is an important commercial timber resource and forest ecosystem component in the southeastern USA. The species occurs in mainly drier sites as an early- to mid-successional species, is fire-adapted, and it plays an important role in the fire ecology of the region. However, shortleaf pine genetics are not well-studied, especially in this era of molecular genetics and genomics. Most genetics research about the species has focused on provenance testing. Generally, shortleaf pine performs well in colder areas, when compared to loblolly pine ( Pinus taeda L.), a close relative, which is faster growing and the most common plantation species in the region. Though not as advanced in genetic improvement as loblolly pine, tree breeders have improved shortleaf pine in one to two generations of selection, and diverse, genetically improved shortleaf pine materials are available to foresters and landowners throughout the southeastern USA. Researchers have also studied the genetic variation of shortleaf pine using various molecular markers and have found that shortleaf pine is generally a prolific outcrosser, a trait it shares with other non-isolated members of the family Pinaceae. In recent years, however, it has shared less genetic material across long ranges, probably because of habitat fragmentation. Various anthropogenic factors also affect shortleaf pine’s future, as recent studies show that shortleaf pine introgression with loblolly pine puts the species—and the resiliency of southeastern forests—at risk. Importantly, fire exclusion is a likely cause of the increase in introgression. Herein, we provide further details and up-to-date genetic information and resources for foresters and ecologists interested in the restoration and management of shortleaf pine.
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Natural hybridization within seed sources of shortleaf pine (Pinus echinata Mill.) and loblolly pine (Pinus taeda L.)
Tree Genetics & Genomes, 2008Co-Authors: C G Tauer, C. Dana NelsonAbstract:Shortleaf and loblolly pine trees ( n = 93 and 102, respectively) from 22 seed sources of the Southwide Southern Pine Seed Source Study plantings or equivalent origin were evaluated for amplified fragment length polymorphism (AFLP) variation. These sampled trees represent shortleaf pine and loblolly pine, as they existed across their native geographic ranges before intensive forest management. Using 17 primer pairs, a total of 96 AFLPs between shortleaf pine and loblolly pine were produced and scored on the sample trees and two control-pollinated F1 interspecies hybrids and their parents. In addition, the well known isocitrate dehydrogenase ( IDH ) isozyme marker was scored for all trees. IDH detected two putative hybrids among the loblolly pine samples and two among the shortleaf pine samples, while either 13 or 12 putative hybrids were detected using all AFLP markers and IDH and either NewHybrids or Structure software, respectively. Results of this study show that later generation hybrids can be reliably identified using AFLP markers and confirmed that IDH is not a definitive marker for detecting hybrids; that is, at least in some seed sources, the alternative species’ IDH allele resides in the source species. Based on all the markers, hybridization frequency varied geographically, ranging from 30% in an Arkansas seed source to 0% in several other seed sources. The hybridization level was higher in populations west of the Mississippi River than in populations east of the river; the shortleaf pine hybridization rates were 16.3% and 2.4% and the loblolly pine rates were 4.5% and 3.3%, west and east of the river, respectively. The results suggest that hybridization between these two species is significant but varies by seed source and species, and the potential for the unintended creation of hybrids should be considered in forest management decisions regarding both natural and artificial regeneration.
Dana C Nelson - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of Long-Term Shortleaf Pine Progeny Tests in the Ouachita and Ozark National Forests, USA
'MDPI AG', 2021Co-Authors: Shaik M. Hossain, Barbara S. Crane, Don C. Bragg, Virginia L. Mcdaniel, Carolyn C. Pike, Dana C NelsonAbstract:Between the late 1970s and the early 1990s, the USDA Forest Service installed 155 shortleaf pine (Pinus echinata Mill.) progeny tests in national forests across the Southern Region of the United States. Using control-pollinated crosses from the Mount Ida Seed Orchard, 84 of these progeny tests were established in the Ouachita and Ozark-St. Francis National Forests in Arkansas and Oklahoma. Each of these 84 test locations had, on average, 33 full-sibling families representing three local geographic seed sources (East Ouachita, West Ouachita, and Ozark). Though largely abandoned years ago, the progeny tests that remain provided an opportunity to determine if significant genetic and genetic × environment variance exists for performance traits (d.b.h., tree height, and survival) decades after installation. In 2018 and 2019, we remeasured d.b.h. and height and determined survival in 15 fully stocked progeny tests. Family variances were significant (p p > 0.05). Seed sources differed significantly (p p > 0.05)
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frequent fire protects shortleaf pine Pinus echinata from introgression by loblolly pine p taeda
Conservation Genetics, 2015Co-Authors: John F Stewart, Rodney E Will, Kevin M Robertson, Dana C NelsonAbstract:Across much of the globe, fire is a major disturbance agent of forest and grassland communities. The removal of fire from previously fire-maintained ecosystems, which has occurred in many areas, changes species composition, favoring later less fire tolerant species over fire-adapted ones. A recent measured increase in the rate of hybridization between the fire-adapted shortleaf pine (Pinus echinata) and less fire-adapted loblolly pine (P. taeda) suggests that introgression may be an emerging threat to shortleaf pine as a genetically distinct species. We used 25 microsatellite markers on seedlings and saplings to test how the use of frequent fire affects the survival of hybrids between the two species by contrasting species makeup and hybridity in regularly burned areas (every 2 years) to that in neighboring unburned areas, both with mixed canopies of loblolly pine, shortleaf pine, and hybrids. The results show that frequent prescribed fire selects against loblolly pine and hybrids, restoring the community to one dominated by shortleaf pine. These results are the first to indicate that frequent fire can resist introgression between two co-occurring native species and that fire exclusion as a land management policy may be having unrecognized deleterious effects on the genetic integrity of species previously isolated from one another based on fire tolerance.
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genetic diversity within and among populations of shortleaf pine Pinus echinata mill and loblolly pine Pinus taeda l
Tree Genetics & Genomes, 2008Co-Authors: C G Tauer, Dana C NelsonAbstract:Shortleaf pine (n=93) and loblolly pine (n=112) trees representing 22 seed sources or 16 physiographic populations were sampled from Southwide Southern Pine Seed Source Study plantings located in Oklahoma, Arkansas, and Mississippi. The sampled trees were grown from short- leaf pine and loblolly pine seeds formed in 1951 and 1952, prior to the start of intensive forest management across their native ranges. Amplification fragment length polymorphism (AFLP) markers were developed and used to study genetic diversity and its structure in these pine species. After screening 48 primer pairs, 17 and 21 pairs were selected that produced 794 and 647 AFLPs in shortleaf pine and loblolly pine, respectively. High-AFLP-based genetic diversity exists within shortleaf pine and loblolly pine, and most (84.73% in shortleaf pine; 87.69% in loblolly pine) of this diversity is maintained within physiographic populations. The high value of unbiased measures of genetic identity and low value of genetic distance for all pairwise comparisons indicates that the populations have similar genetic structures. For shortleaf pine, there was no significant correlation between geographic distance and genetic distance (r=0.28), while for loblolly pine there was a weak but significant correlation (r=0.51).
C G Tauer - One of the best experts on this subject based on the ideXlab platform.
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Natural hybridization within seed sources of shortleaf pine (Pinus echinata Mill.) and loblolly pine (Pinus taeda L.)
Tree Genetics & Genomes, 2008Co-Authors: C G Tauer, C. Dana NelsonAbstract:Shortleaf and loblolly pine trees ( n = 93 and 102, respectively) from 22 seed sources of the Southwide Southern Pine Seed Source Study plantings or equivalent origin were evaluated for amplified fragment length polymorphism (AFLP) variation. These sampled trees represent shortleaf pine and loblolly pine, as they existed across their native geographic ranges before intensive forest management. Using 17 primer pairs, a total of 96 AFLPs between shortleaf pine and loblolly pine were produced and scored on the sample trees and two control-pollinated F1 interspecies hybrids and their parents. In addition, the well known isocitrate dehydrogenase ( IDH ) isozyme marker was scored for all trees. IDH detected two putative hybrids among the loblolly pine samples and two among the shortleaf pine samples, while either 13 or 12 putative hybrids were detected using all AFLP markers and IDH and either NewHybrids or Structure software, respectively. Results of this study show that later generation hybrids can be reliably identified using AFLP markers and confirmed that IDH is not a definitive marker for detecting hybrids; that is, at least in some seed sources, the alternative species’ IDH allele resides in the source species. Based on all the markers, hybridization frequency varied geographically, ranging from 30% in an Arkansas seed source to 0% in several other seed sources. The hybridization level was higher in populations west of the Mississippi River than in populations east of the river; the shortleaf pine hybridization rates were 16.3% and 2.4% and the loblolly pine rates were 4.5% and 3.3%, west and east of the river, respectively. The results suggest that hybridization between these two species is significant but varies by seed source and species, and the potential for the unintended creation of hybrids should be considered in forest management decisions regarding both natural and artificial regeneration.
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genetic diversity within and among populations of shortleaf pine Pinus echinata mill and loblolly pine Pinus taeda l
Tree Genetics & Genomes, 2008Co-Authors: C G Tauer, Dana C NelsonAbstract:Shortleaf pine (n=93) and loblolly pine (n=112) trees representing 22 seed sources or 16 physiographic populations were sampled from Southwide Southern Pine Seed Source Study plantings located in Oklahoma, Arkansas, and Mississippi. The sampled trees were grown from short- leaf pine and loblolly pine seeds formed in 1951 and 1952, prior to the start of intensive forest management across their native ranges. Amplification fragment length polymorphism (AFLP) markers were developed and used to study genetic diversity and its structure in these pine species. After screening 48 primer pairs, 17 and 21 pairs were selected that produced 794 and 647 AFLPs in shortleaf pine and loblolly pine, respectively. High-AFLP-based genetic diversity exists within shortleaf pine and loblolly pine, and most (84.73% in shortleaf pine; 87.69% in loblolly pine) of this diversity is maintained within physiographic populations. The high value of unbiased measures of genetic identity and low value of genetic distance for all pairwise comparisons indicates that the populations have similar genetic structures. For shortleaf pine, there was no significant correlation between geographic distance and genetic distance (r=0.28), while for loblolly pine there was a weak but significant correlation (r=0.51).
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paternal chloroplast inheritance patterns in pine hybrids detected with trnl trnf intergenic region polymorphism
Theoretical and Applied Genetics, 2002Co-Authors: Jiwang Chen, C G Tauer, Yinghua HuangAbstract:The inheritance patterns of the chloroplast genomes of shortleaf pine (Pinus echinata Mill.), loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) were investigated through the trnL–trnF intergenic spacer polymorphism analysis. The DNA sequences of this spacer differ among these three closely related Pinus species. A modified 'cold' PCR-SSCP (single-strand conformation polymorphism) analysis of this spacer shows that the artificial hybrids (F1) from the shortleaf pine (seed parent) × loblolly pine (pollen parent) cross, exhibit the loblolly pine profile. Additionally, nine putative hybrids between shortleaf pine and loblolly pine, previously identified by the IDH (Isocitrate dehydrogenase) allozyme marker, presented the shortleaf pine profile indicating that shortleaf pine, not loblolly pine, sired all of the putative hybrids. Nondenatured polyacrylamide-gel electrophoresis of the trnL–trnF intergenic spacer demonstrated that the artificial hybrids (F1) from the cross, slash pine (seed parent) × shortleaf pine (pollen parent), present the shortleaf pine profile. Those results confirmed that the chloroplast genome is paternally inherited in these three species of the genus Pinus. The significance of the trnL–trnF intergenic region polymorphism and our modified 'cold' SSCP protocol for population genetic studies is discussed.
Amanda Carla Newman - One of the best experts on this subject based on the ideXlab platform.
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restoration of shortleaf pine Pinus echinata mill bluestem andropogon gerardii vitman and schizachyrium scoparium michx nash communities in the southern appalachians
2008Co-Authors: Amanda Carla NewmanAbstract:Fire suppression and southern pine beetle (Dendroctonus frontalis Zimm.) outbreaks have contributed to the decline of native shortleaf pine (Pinus echinata Mill.) - bluestem grass (Andropogon gerardii Vitman and Schizachyrium scoparium (Michx.) Nash) communities in the southern Appalachians. We evaluated the effects of herbicide application (nursery) and selective felling and prescribed burning (field) on planted shortleaf pine seedling growth and survival and broadcasted bluestem grass seed establishment and cover. Greatest shortleaf pine growth occurred within the fell with burn treatment and the herbicide application treatments. Soil moisture and aspect influenced seedling survival while maximum flame temperature and overstory mortality influenced bluestem grass presence. Greatest big bluestem cover occurred within the shortleaf pine- bluestem grass herbicide treatment and greatest little bluestem cover occurred within the bluestem grass treatment. Herbicide application and felling with prescribed burning may be used to increase shortleaf pine growth rates while promoting the establishment of bluestem grasses.
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RESTORATION OF SHORTLEAF PINE (Pinus echinata MILL) – BLUESTEM (ANDROPOGON GERARDII VITMAN AND SCHIZACHYRIUM SCOPARIUM (MICHX.) NASH) COMMUNITIES IN THE SOUTHERN APPALACHIANS by
2008Co-Authors: Amanda Carla NewmanAbstract:(Under the Direction of Ronald L. Hendrick) Fire suppression and southern pine beetle (Dendroctonus frontalis Zimm.) outbreaks have contributed to the decline of native shortleaf pine (Pinus echinata Mill.)- bluestem grass (Andropogon gerardii Vitman and Schizachyrium scoparium (Michx.) Nash) communities in the southern Appalachians. We evaluated the effects of herbicide application (nursery) and selective felling and prescribed burning (field) on planted shortleaf pine seedling growth and survival and broadcasted bluestem grass seed establishment and cover. Greatest shortleaf pine growth occurred within the fell with burn treatment and the herbicide application treatments. Soil moisture and aspect influenced seedling survival while maximum flame temperature and overstory mortality influenced bluestem grass presence. Greatest big bluestem cover occurred within the shortleaf pine- bluestem grass herbicide treatment and greatest little bluestem cover occurred within the bluestem grass treatment. Herbicide application and felling with prescribed burning may be used to increase shortleaf pine growth rates while promoting the establishment of bluestem grasses