Identification of a Natural Hybrid between Castanopsis sclerophylla and Castanopsis tibetana (Fagaceae) Based on Chloroplast and Nuclear DNA Sequences

Castanopsis × kuchugouzhui Huang et Y. T. Chang was recorded in Flora Reipublicae Popularis Sinicae (FRPS) as a hybrid species on Yuelushan mountain, but it is treated as a hybrid between Castanopsis sclerophylla (Lindl.) Schott. and Castanopsis tibetana Hance in Flora of China. After a thorough investigation on Yuelushan mountain, we found a population of C. sclerophylla and one individual of C. × kuchugouzhui, but no living individual of C. tibetana. We collected C. × kuchugouzhui, and we sampled 42 individuals of C. sclerophylla from Yuelushan and Xiushui and 43 individuals of C. tibetana from Liangyeshan and Xiushui. We used chloroplast DNA sequences and 29 nuclear microsatellite markers to investigate if C. × kuchugouzhui is a natural hybrid between C. sclerophylla and C. tibetana. The chloroplast haplotype analysis showed that C. × kuchugouzhui shared haplotype H2 with C. sclerophylla on Yuelushan. The STRUCTURE analysis identified two distinct genetic pools that corresponded well to C. sclerophylla and C. tibetana, revealing the genetic admixture of C. × kuchugouzhui. Furthermore, the NewHybrids analysis suggested that C. × kuchugouzhui is an F2 hybrid between C. sclerophylla and C. tibetana. Our results confirm that C. × kuchugouzhui recorded in FRPS is a rare hybrid between C. sclerophylla and C. tibetana.

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Proplastid Dna Synthesis at Pachytene in Pollen Mother Cells of Lilium Henryi

Journal of Cell Science ◽

10.1242/jcs.56.1.293 ◽

1982 ◽

Vol 56 (1) ◽

pp. 293-302

Author(s):

D. R. SMYTH

Keyword(s):

Dna Synthesis ◽

Dna Sequences ◽

Nuclear Dna ◽

Buoyant Density ◽

Plastid Dna ◽

Electron Microscopic ◽

Pollen Mother Cells ◽

Specific Hybridization ◽

Chloroplast Dna Sequences ◽

Mother Cells

About three-quarters of the DNA synthesis occurring in pachytene pollen mother cells of Lilium henryi takes place in proplastids. Only around 15% can be attributed to mitochondrial labelling and 10% to nuclear DNA synthesis. Label was identified in the proplastid genome by its location in electron microscopic autoradiographs, by its buoyant density (1.698 g/ml), and by its specific hybridization to chloroplast DNA sequences from spinach. Proplastids, while apparently not dividing at pachytene, may be replicating their DNA in readiness for subsequent proliferation in developing microspores. The annealing properties of plastid DNA closely parallel those of labelled pachytene DNA sequences implicated in meiotic exchange events.

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Ottelia guanyangensis (Hydrocharitaceae), a new species from southwestern China

Phytotaxa ◽

10.11646/phytotaxa.361.3.5 ◽

2018 ◽

Vol 361 (3) ◽

pp. 294 ◽

Cited By ~ 4

Author(s):

ZHI-ZHONG LI ◽

KUO LIAO ◽

CHUN-YU ZOU ◽

YAN LIU ◽

GUANG-WAN HU ◽

...

Keyword(s):

Phylogenetic Analysis ◽

New Species ◽

Dna Sequences ◽

Internal Transcribed Spacer ◽

Aquatic Plant ◽

Nuclear Dna ◽

Southwestern China ◽

Molecular Phylogenetic ◽

Chloroplast Dna Sequences ◽

A New Species

Ottelia guanyangensis (Hydrocharitaceae), a new species from southwestern China, is described and illustrated. This aquatic plant is a perennial, submersed herb with bisexual flowers and a hexagonal-cylindric fruit. It is related to O. acuminata var. songmingensis and O. balansae but differs from these two taxa by its bisexual flowers, spathe with 2–5 flowers, trinerved leaf with obvious cross veins, and a winged, hexagonal-cylindric fruit. Molecular phylogenetic analysis based on nuclear DNA internal transcribed spacer (ITS) sequences and three chloroplast DNA sequences (rbcL, trnK5’ intron and trnS-trnG) resolves O. guanyangensis as a distinct clade, which further justifies its recognition as a new species.

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Rarity, taxonomy and genetics: the chequered history of Grevillea williamsonii (Proteaceae)

Pacific Conservation Biology ◽

10.1071/pc17050 ◽

2018 ◽

Vol 24 (3) ◽

pp. 329

Author(s):

Elizabeth A. James ◽

Gillian K. Brown ◽

Rebecca Jordan ◽

Daniel J. Ohlsen

Keyword(s):

Dna Sequences ◽

Conservation Status ◽

Taxonomic Status ◽

Haplotype Network ◽

Common Species ◽

Rare Plants ◽

Threatened Taxa ◽

History Of ◽

Nuclear Microsatellite ◽

Chloroplast Dna Sequences

Resolving uncertainty surrounding the taxonomic and conservation status of rare plants is of utmost importance to enable effective allocation of the limited resources available for conserving biodiversity. Prioritising threatened taxa that are more appropriately regarded as synonymous with more common species represents a waste of resources. Such a scenario may apply to the Australian entity Grevillea williamsonii and consequently its taxonomic status was investigated using chloroplast DNA sequences and nuclear microsatellite data. Haplotype network and genetic structure analyses showed that G. williamsonii was not genetically distinct from, and should be synonymised with, the variable and morphologically similar but more common G. aquifolium. This study highlights the benefit of undertaking genetic analyses where questionable taxonomic status biases conservation prioritisation and management decisions.

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Relationships of North American members of Rhodiola (Crassulaceae)

Botany ◽

10.1139/cjb-2014-0009 ◽

2014 ◽

Vol 92 (12) ◽

pp. 901-910 ◽

Cited By ~ 3

Author(s):

Joel P. Olfelt ◽

William A. Freyman

Keyword(s):

Dna Sequences ◽

North American ◽

Phylogenetic Analyses ◽

Black Hills ◽

Trnl Intron ◽

The North ◽

Alpine Habitats ◽

Rare And Endangered ◽

Chloroplast Dna Sequences ◽

Rhodiola Integrifolia

Taxa of Rhodiola L. (Crassulaceae) generally grow in arctic or alpine habitats. Some Rhodiola species are used medicinally, one taxon, Rhodiola integrifolia Raf. subsp. leedyi (Rosend. & J.W.Moore) Moran, (Leedy’s roseroot), is rare and endangered, and the group’s biogeography in North America is intriguing because of distributional disjunctions and the possibility that Rhodiola rhodantha (A.Gray) H.Jacobsen (2n = 7II) and Rhodiola rosea L. (2n = 11II) hybridized to form Rhodiola integrifolia Raf. (2n = 18II). Recent studies of the North American Rhodiola suggest that the group’s current taxonomy is misleading. We analyzed nuclear and chloroplast DNA sequences (internal transcribed spacer (ITS), trnL intron, trnL–trnF spacer, trnS–trnG spacer) from the North American Rhodiola taxa. We combined our data with GenBank sequences from Asian Rhodiola species, performed parsimony, maximum likelihood (ML), and Bayesian phylogenetic analyses, and applied a Bayesian clock model to the ITS data. Our analyses reveal two major Rhodiola clades, suggest that hybridization between R. rhodantha and R. rosea lineages was possible, show two distinct clades within R. integrifolia, and demonstrate that a Black Hills, South Dakota, Rhodiola population should be reclassified as Leedy’s roseroot. We recommend that R. integrifolia be revised, and that the Black Hills Leedy’s roseroot population be managed as part of that rare and endangered taxon.

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