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Zhiduan Chen - One of the best experts on this subject based on the ideXlab platform.
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comparative flower development of juglans regia cyclocarya paliurus and engelhardia spicata homology of floral envelopes in Juglandaceae
Botanical Journal of the Linnean Society, 2016Co-Authors: Ruozhu Lin, Junyi Zhu, Zhiduan ChenAbstract:Homology among reproductive structures is pivotal for understanding angiosperm evolution. In Juglandaceae, homologies of floral parts have been disputed due to morphological variability in flowers. Previous interpretations were based mainly on mature flowers and lacked developmental studies. We investigated the unisexual flower development of Juglans regia, Cyclocarya paliurus and Engelhardia spicata using scanning electron microscopy. The ‘floral envelope’ of staminate flowers in J. regia and C. paliurus consists of a bract and several tepals. Six tepals are initiated in a whorled pattern in J. regia, whereas four to six tepals are arranged in a variable pattern in C. paliurus. The three-lobed bract of E. spicata results from the cleavage of an entire bract, rather than adnation of the bract and its bracteoles. Pistillate flowers of J. regia and C. paliurus, subtended by a bract and a horseshoe-shaped bracteole, usually have four tepals initiating simultaneously in one whorl. The organogenesis patterns of the ‘floral envelope’ and stamens in staminate flowers show greater diversity, indicating different degrees of reduction among genera. Our floral developmental data support the division of Juglandaceae into two subfamilies and then further into three tribes.
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integrated fossil and molecular data reveal the biogeographic diversification of the eastern asian eastern north american disjunct hickory genus carya nutt
PLOS ONE, 2013Co-Authors: Jingbo Zhang, Steven R Manchester, Ruiqi Li, Xiaoguo Xiang, Zhiduan ChenAbstract:The hickory genus (Carya) contains ca. 17 species distributed in subtropical and tropical regions of eastern Asia and subtropical to temperate regions of eastern North America. Previously, the phylogenetic relationships between eastern Asian and eastern North American species of Carya were not fully confirmed even with an extensive sampling, biogeographic and diversification patterns had thus never been investigated in a phylogenetic context. We sampled 17 species of Carya and 15 species representing all other genera of the Juglandaceae as outgroups, with eight nuclear and plastid loci to reconstruct the phylogeny of Carya. The phylogenetic positions of seven extinct genera of the Juglandaceae were inferred using morphological characters and the molecular phylogeny as a backbone constraint. Divergence times within Carya were estimated with relaxed Bayesian dating. Biogeographic analyses were performed in DIVA and LAGRANGE. Diversification rates were inferred by LASER and APE packages. Our results support two major clades within Carya, corresponding to the lineages of eastern Asia and eastern North America. The split between the two disjunct clades is estimated to be 21.58 (95% HPD 11.07-35.51) Ma. Genus-level DIVA and LAGRANGE analyses incorporating both extant and extinct genera of the Juglandaceae suggested that Carya originated in North America, and migrated to Eurasia during the early Tertiary via the North Atlantic land bridge. Fragmentation of the distribution caused by global cooling in the late Tertiary resulted in the current disjunction. The diversification rate of hickories in eastern North America appeared to be higher than that in eastern Asia, which is ascribed to greater ecological opportunities, key morphological innovations, and polyploidy.
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organogenesis of the inflorescence and flowers in platycarya strobilacea Juglandaceae
International Journal of Plant Sciences, 2005Co-Authors: Zhiduan ChenAbstract:The reproductive structures of the monotypic genus Platycarya (Juglandaceae), in particular the nature of the fruit wings, have been interpreted variously. We investigated organogenesis of inflorescence and flowers with scanning electron microscopy (SEM). This is the first SEM study to show the whole developmental process of male, female, and bisexual flowers in a member of the Fagales. In staminate and bisexual flowers, only a subtending bract is present, while bracteole and perianth are absent. Four to 10 stamen primordia of different sizes are arranged as an irregular circle or two semicircles. With further development of the stamens, the receptacle, which is fused to the base of the bract, enlarges, and the whorled arrangement of stamens becomes less and less distinct. In pistillate flowers, the transversely ellipsoidal floral primordium develops a central depression. Two bracteoles are initiated in the lateral position of the floral primordium. Soon, the inconspicuous circular perianth primordium app...
Jingbo Zhang - One of the best experts on this subject based on the ideXlab platform.
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integrated fossil and molecular data reveal the biogeographic diversification of the eastern asian eastern north american disjunct hickory genus carya nutt
PLOS ONE, 2013Co-Authors: Jingbo Zhang, Steven R Manchester, Ruiqi Li, Xiaoguo Xiang, Zhiduan ChenAbstract:The hickory genus (Carya) contains ca. 17 species distributed in subtropical and tropical regions of eastern Asia and subtropical to temperate regions of eastern North America. Previously, the phylogenetic relationships between eastern Asian and eastern North American species of Carya were not fully confirmed even with an extensive sampling, biogeographic and diversification patterns had thus never been investigated in a phylogenetic context. We sampled 17 species of Carya and 15 species representing all other genera of the Juglandaceae as outgroups, with eight nuclear and plastid loci to reconstruct the phylogeny of Carya. The phylogenetic positions of seven extinct genera of the Juglandaceae were inferred using morphological characters and the molecular phylogeny as a backbone constraint. Divergence times within Carya were estimated with relaxed Bayesian dating. Biogeographic analyses were performed in DIVA and LAGRANGE. Diversification rates were inferred by LASER and APE packages. Our results support two major clades within Carya, corresponding to the lineages of eastern Asia and eastern North America. The split between the two disjunct clades is estimated to be 21.58 (95% HPD 11.07-35.51) Ma. Genus-level DIVA and LAGRANGE analyses incorporating both extant and extinct genera of the Juglandaceae suggested that Carya originated in North America, and migrated to Eurasia during the early Tertiary via the North Atlantic land bridge. Fragmentation of the distribution caused by global cooling in the late Tertiary resulted in the current disjunction. The diversification rate of hickories in eastern North America appeared to be higher than that in eastern Asia, which is ascribed to greater ecological opportunities, key morphological innovations, and polyploidy.
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molecular identification of species in Juglandaceae a tiered method
Journal of Systematics and Evolution, 2011Co-Authors: Xiaoguo Xiang, Jingbo Zhang, L U Anming, L I RuiqiAbstract:DNA barcoding is a method of species identification and recognition using DNA sequence data. A tiered or multilocus method has been recommended for barcoding plant species. In this study, we sampled 196 individuals representing 9 genera and 54 species of Juglandaceae to investigate the utility of the four potential barcoding loci (rbcL, matK, trnH-psbA, and internal transcribed spacer (ITS)). Our results show that all four DNA regions are easy to amplify and sequence. In the four tested DNA regions, ITS has the most variable information, and rbcL has the least. At generic level, seven of nine genera can be efficiently identified by matK. At species level, ITS has higher interspecific p-distance than the trnH-psbA region. Difficult to align in the whole family, ITS showed heterogeneous variability among different genera. Except for the monotypic genera (Cyclocarya, Annamocarya, Platycarya), ITS appeared to have limited power for species identification within the Carya and Engelhardia complex, and have no power for Juglans or Pterocarya. Overall, our results confirmed that a multilocus tiered method for plant barcoding was applicable and practicable. With higher priority, matK is proposed as the first-tier DNA region for genus discrimination, and the second locus at species level should have enough stable variable characters.
Steven R Manchester - One of the best experts on this subject based on the ideXlab platform.
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oligocene fossil winged fruits of tribe engelhardieae Juglandaceae from the ningming basin of guangxi province south china
2014Co-Authors: Steven R Manchester, Yunfa Chen, Zhuqiu Song, Hongshan WangAbstract:Two new types of fossil winged fruits of tribe Engelhardieae (Juglandaceae) are recognized in the Oligocene sediment from the Ningming Basin of Guangxi Province, south China, Palaeocarya guangxiensis sp.nov., and Alfaropsis koreanica (Oishi) Iljinskaya. The Alfaropsis koreanica fossils reported here are from the lowest latitude yet documented for the Oligocene. These fossils augment previously described engelhardioid fruit species from the same locality, Palaeocarya guangxiensis Li et Chen and Palaeocarya ningmingensis Li et Chen providing additional evidence for diversity of Juglandaceae in the Paleogene of South China, and new data for the investigation of the origin and evolution and paleobiogeographical history of the juglandaceous tribe Engelhardieae.
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integrated fossil and molecular data reveal the biogeographic diversification of the eastern asian eastern north american disjunct hickory genus carya nutt
PLOS ONE, 2013Co-Authors: Jingbo Zhang, Steven R Manchester, Ruiqi Li, Xiaoguo Xiang, Zhiduan ChenAbstract:The hickory genus (Carya) contains ca. 17 species distributed in subtropical and tropical regions of eastern Asia and subtropical to temperate regions of eastern North America. Previously, the phylogenetic relationships between eastern Asian and eastern North American species of Carya were not fully confirmed even with an extensive sampling, biogeographic and diversification patterns had thus never been investigated in a phylogenetic context. We sampled 17 species of Carya and 15 species representing all other genera of the Juglandaceae as outgroups, with eight nuclear and plastid loci to reconstruct the phylogeny of Carya. The phylogenetic positions of seven extinct genera of the Juglandaceae were inferred using morphological characters and the molecular phylogeny as a backbone constraint. Divergence times within Carya were estimated with relaxed Bayesian dating. Biogeographic analyses were performed in DIVA and LAGRANGE. Diversification rates were inferred by LASER and APE packages. Our results support two major clades within Carya, corresponding to the lineages of eastern Asia and eastern North America. The split between the two disjunct clades is estimated to be 21.58 (95% HPD 11.07-35.51) Ma. Genus-level DIVA and LAGRANGE analyses incorporating both extant and extinct genera of the Juglandaceae suggested that Carya originated in North America, and migrated to Eurasia during the early Tertiary via the North Atlantic land bridge. Fragmentation of the distribution caused by global cooling in the late Tertiary resulted in the current disjunction. The diversification rate of hickories in eastern North America appeared to be higher than that in eastern Asia, which is ascribed to greater ecological opportunities, key morphological innovations, and polyploidy.
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reproductive and vegetative morphology of polyptera Juglandaceae from the paleocene of wyoming and montana
American Journal of Botany, 1997Co-Authors: Steven R Manchester, David L DilcherAbstract:The morphology, systematics, and ecology of the extinct juglandaceous genus Polyptera are interpreted on the basis of infructescences, fruits, staminate catkins, pollen, and compound leaves from the Paleocene of Wyoming and Montana. The elongate infructescences of Polyptera manningiibear numerous helically arranged sessile fruits. The fruit is a pyramidal nut with a vascularized husk and a multilobed disk-like wing adaptive for wind dispersal. Associated staminate catkins bear numerous helically arranged florets, each with six or more stamens. Pollen from the anthers is triporate and isopolar, with ultrastructure diagnostic of Juglandaceae, but with a pattern of exinous thinning characteristic of the extinct dispersed pollen type Maceopolipollenites anellus (Nichols et Ott) comb. nov. The correlated leaves, Juglandiphyllites glabra (Brown ex Watt) comb. nov., are deciduous, pinnately compound, and have five to seven petiolulate finely serrate leaflets. Systematically, Polyptera shows relationships both with the Hicorieae and the Juglandeae. Occurrences in the Torrejonian and Tiffanian stages of the Paleocene place Polyptera as the oldest unequivocal record of Juglandaceae. Polyptera manningii typically occurs in low-diversity assemblages of 8‐15 species, and usually is a dominant or subdominant constituent of floodplain assemblages. It may have been an early-successional colonizer.
Ruiqi Li - One of the best experts on this subject based on the ideXlab platform.
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integrated fossil and molecular data reveal the biogeographic diversification of the eastern asian eastern north american disjunct hickory genus carya nutt
PLOS ONE, 2013Co-Authors: Jingbo Zhang, Steven R Manchester, Ruiqi Li, Xiaoguo Xiang, Zhiduan ChenAbstract:The hickory genus (Carya) contains ca. 17 species distributed in subtropical and tropical regions of eastern Asia and subtropical to temperate regions of eastern North America. Previously, the phylogenetic relationships between eastern Asian and eastern North American species of Carya were not fully confirmed even with an extensive sampling, biogeographic and diversification patterns had thus never been investigated in a phylogenetic context. We sampled 17 species of Carya and 15 species representing all other genera of the Juglandaceae as outgroups, with eight nuclear and plastid loci to reconstruct the phylogeny of Carya. The phylogenetic positions of seven extinct genera of the Juglandaceae were inferred using morphological characters and the molecular phylogeny as a backbone constraint. Divergence times within Carya were estimated with relaxed Bayesian dating. Biogeographic analyses were performed in DIVA and LAGRANGE. Diversification rates were inferred by LASER and APE packages. Our results support two major clades within Carya, corresponding to the lineages of eastern Asia and eastern North America. The split between the two disjunct clades is estimated to be 21.58 (95% HPD 11.07-35.51) Ma. Genus-level DIVA and LAGRANGE analyses incorporating both extant and extinct genera of the Juglandaceae suggested that Carya originated in North America, and migrated to Eurasia during the early Tertiary via the North Atlantic land bridge. Fragmentation of the distribution caused by global cooling in the late Tertiary resulted in the current disjunction. The diversification rate of hickories in eastern North America appeared to be higher than that in eastern Asia, which is ascribed to greater ecological opportunities, key morphological innovations, and polyploidy.
Xiaoguo Xiang - One of the best experts on this subject based on the ideXlab platform.
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characterization of the complete chloroplast genome of pterocarya macroptera var delavayi Juglandaceae
Mitochondrial DNA Part B, 2021Co-Authors: Hua Yan, Xiaoguo Xiang, Jisi Zhang, Chunce GuoAbstract:In this study, the complete chloroplast genome sequence of Pterocarya macroptera var. delavayi was reported and characterized. The chloroplast genome is 160,168 bp in length, and consists the typic...
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integrated fossil and molecular data reveal the biogeographic diversification of the eastern asian eastern north american disjunct hickory genus carya nutt
PLOS ONE, 2013Co-Authors: Jingbo Zhang, Steven R Manchester, Ruiqi Li, Xiaoguo Xiang, Zhiduan ChenAbstract:The hickory genus (Carya) contains ca. 17 species distributed in subtropical and tropical regions of eastern Asia and subtropical to temperate regions of eastern North America. Previously, the phylogenetic relationships between eastern Asian and eastern North American species of Carya were not fully confirmed even with an extensive sampling, biogeographic and diversification patterns had thus never been investigated in a phylogenetic context. We sampled 17 species of Carya and 15 species representing all other genera of the Juglandaceae as outgroups, with eight nuclear and plastid loci to reconstruct the phylogeny of Carya. The phylogenetic positions of seven extinct genera of the Juglandaceae were inferred using morphological characters and the molecular phylogeny as a backbone constraint. Divergence times within Carya were estimated with relaxed Bayesian dating. Biogeographic analyses were performed in DIVA and LAGRANGE. Diversification rates were inferred by LASER and APE packages. Our results support two major clades within Carya, corresponding to the lineages of eastern Asia and eastern North America. The split between the two disjunct clades is estimated to be 21.58 (95% HPD 11.07-35.51) Ma. Genus-level DIVA and LAGRANGE analyses incorporating both extant and extinct genera of the Juglandaceae suggested that Carya originated in North America, and migrated to Eurasia during the early Tertiary via the North Atlantic land bridge. Fragmentation of the distribution caused by global cooling in the late Tertiary resulted in the current disjunction. The diversification rate of hickories in eastern North America appeared to be higher than that in eastern Asia, which is ascribed to greater ecological opportunities, key morphological innovations, and polyploidy.
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molecular identification of species in Juglandaceae a tiered method
Journal of Systematics and Evolution, 2011Co-Authors: Xiaoguo Xiang, Jingbo Zhang, L U Anming, L I RuiqiAbstract:DNA barcoding is a method of species identification and recognition using DNA sequence data. A tiered or multilocus method has been recommended for barcoding plant species. In this study, we sampled 196 individuals representing 9 genera and 54 species of Juglandaceae to investigate the utility of the four potential barcoding loci (rbcL, matK, trnH-psbA, and internal transcribed spacer (ITS)). Our results show that all four DNA regions are easy to amplify and sequence. In the four tested DNA regions, ITS has the most variable information, and rbcL has the least. At generic level, seven of nine genera can be efficiently identified by matK. At species level, ITS has higher interspecific p-distance than the trnH-psbA region. Difficult to align in the whole family, ITS showed heterogeneous variability among different genera. Except for the monotypic genera (Cyclocarya, Annamocarya, Platycarya), ITS appeared to have limited power for species identification within the Carya and Engelhardia complex, and have no power for Juglans or Pterocarya. Overall, our results confirmed that a multilocus tiered method for plant barcoding was applicable and practicable. With higher priority, matK is proposed as the first-tier DNA region for genus discrimination, and the second locus at species level should have enough stable variable characters.
