Publications by authors named "Xiaoguo Xiang"

The southeastward extrusion of Indochina along the Ailao Shan-Red River shear zone (ARSZ) is one of two of the most prominent consequences of the India-Asia collision. This plate-scale extrusion has greatly changed Southeast Asian topography and drainage patterns and effected regional climate and biotic evolution. However, little is known about how Indochina was extruded toward the southeast over time.

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is an orchid genus containing about 70 species in tropical and subtropical Asia with high morphological diversity. The phylogenetic relationships among this genus have not been fully resolved, and the plastome evolution has not been investigated either. In this study, five plastomes of were newly reported, and sixteen plastomes of were used to conduct comparative and phylogenetic analyses.

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Background: The genus Triplostegia contains two recognized species, T. glandulifera and T. grandiflora, but its phylogenetic position and species delimitation remain controversial.

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Species richness is spatially heterogeneous even in the hyperdiverse tropical floras. The main cause of uneven species richness among the four tropical regions are hot debated. To date, higher net diversification rates and/or longer colonization time have been usually proposed to contribute to this pattern.

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Article Synopsis
  • Trichosporeae is a diverse and taxonomically complex tribe within Gesneriaceae, making it difficult to clarify its phylogenetic relationships.
  • Recent advances in plastid phylogenomics were utilized to study the genetic relationships among 79 species and seven subtribes within Trichosporeae, revealing insights into their genomic structure and evolutionary history.
  • The research identified key genetic markers, significant gene variations, and conserved codon usage patterns, contributing to a better understanding of the tribe's genetic diversity and aiding future conservation efforts.
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The molecular mechanisms of freezing tolerance are unresolved in the perennial trees that can survive under much lower freezing temperatures than annual herbs. Since natural conditions involve many factors and temperature usually cannot be controlled, field experiments alone cannot directly identify the effects of freezing stress. Lab experiments are insufficient for trees to complete cold acclimation and cannot reflect natural freezing-stress responses.

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The tropical Asian and Australasian floras have a close relationship, and is a vital distribution pattern of seed plants worldwide. As estimated, more than 81 families and 225 genera of seed plants distributed between tropical Asia and Australasia. However, the evolutionary dynamics of two floras were still vague.

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  • The study investigates the shift between evergreen and deciduous leaf habits in East Asian forest trees, particularly focusing on the Litsea complex, to understand how these traits adapt to past climatic changes.
  • Researchers reconstructed the evolutionary history of Litsea using genomic data and identified key periods, revealing that evergreen broadleaved forests first appeared during the Early Eocene due to warmer conditions.
  • The transition to deciduous traits occurred in response to cooling climates in the Middle to Late Eocene, while the rise of monsoon conditions by the Early Miocene accelerated the development of evergreen traits that define today's forests.
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The dominant species of a biome can be regarded as its genuine indicator. Evergreen broadleaved forests (EBLFs) in subtropical East Asia harbor high levels of species biodiversity and endemism and are vital to regional carbon storage and cycling. However, the historical assembly of this unique biome is still controversial.

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Caves are home to unique and fragile biotas with high levels of endemism. However, little is known about how the biotic colonization of caves has developed over time, especially in caves from middle and low latitudes. Subtropical East Asia holds the world's largest karst landform with numerous ancient caves, which harbor a high diversity of cave-dwelling organisms and are regarded as a biodiversity hotspot.

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origins and dispersal of taxa have played important roles in the assembly of island-like biodiversity hotspots. Insular limestone karsts in Southeast Asia are hotspots of biodiversity and endemism, but the immigration processes of their unique floras are still poorly known. Here, we used Gesneriaceae as a proxy to investigate the immigration dynamics of tropical and subtropical Southeast Asian karst floras.

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Fagales are an order of woody plants and comprise more than 1,100 species, most of which produce economically important timbers, nuts, and fruits. Their nuclear and plastid genomes are well-sequenced and provided valuable resources to study their phylogeny, breeding, resistance, etc. However, little is known about the mitochondrial genomes (mitogenomes), which hinder a full understanding of their genome evolution.

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Temperate South American-Asian disjunct distributions are the most unusual in organisms, and challenging to explain. Here, we address the origin of this unusual disjunction in Lardizabalaceae using explicit models and molecular data. The family (c.

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Conventional microsatellite (simple sequence repeat, SSR) genotyping methods cannot accurately identify polyploid genotypes leading to allele dosage uncertainty, introducing biases in population genetic analysis. Here, a new SSR genotyping method was developed to directly infer accurate polyploid genotypes. The frequency distribution of SSR sequences was obtained based on deep-coverage high-throughput sequencing data.

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Article Synopsis
  • * This genome includes 136 unique genes: 88 are protein-coding genes, 40 are tRNA genes, and 8 are rRNA genes, with a GC content of 36.2%.
  • * Phylogenetic analysis shows that this plant variety is closely related to another unspecified species.
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The subtropical evergreen broadleaved forests (EBLFs) inhabit large areas of East Asia and harbor rich biodiversity and high endemism. However, the origin and evolution of biodiversity of East Asian subtropical EBLFs remain poorly understood. Here, we used Mahonia (Berberidaceae), an eastern Asian-western North American disjunct evergreen genus, to obtain new insights into the historical assembly of this biome.

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The tribe Pachygoneae consists of four genera with about 40 species, primarily distributed in tropical and subtropical Asia and America, also in Australasia and Africa. This tribe presents an ideal model to investigate the origin of the tropical and subtropical amphi-Pacific disjunction pattern. More specifically, it allows us to test whether the tropical lineages diverged earlier than the subtropical ones during the fragmentation of the boreotropical flora.

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Subtropical forest is recognized as an important global vegetation type with high levels of plant species richness. However, the mechanisms underlying its diversity remain poorly understood. Here, we assessed the roles of environmental drivers and evolutionary dynamics (time-for-speciation and diversification rate) in shaping species richness patterns across China for a major subtropical plant group, the tea family (Theaceae s.

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The limestone areas in south China are a major biodiversity hotspot for terrestrial biomes. , with 34 species and 5 varieties, mainly distributed in south China, is one of the characteristic plant groups in limestone areas. , a new species of Gesneriaceae from limestone areas in Guizhou, China, is described and illustrated.

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Background: Numerous studies have favored dispersal (colonization) over vicariance (past fragmentation) events to explain eastern Asian-North American distribution patterns. In plants, however the disjunction between eastern Asia and western North America has been rarely examined using the integration of phylogenetic, molecular dating, and biogeographical methods. Meanwhile, the biogeographic patterns within eastern Asia remain poorly understood.

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