Plant Diversity最新文献

•Since the Anthropocene, both climate change and human activities have exerted increasingly profound impacts on QTP plant diversity.•This special section compiles research and reviews on changes in plant diversity across the QTP during the Anthropocene.

As the highest and largest plateau in the world, the Qinghai-Tibet Plateau (QTP) covers wide geological, topographical and climatic gradients and thus acts as a major center for biodiversity and houses a diverse array of high elevation ecosystems. Together these factors make the QTP a critical ecological shield for Asia. However, the composition, structure and function of plant diversity in QTP has experienced profound changes in recent decades. Long-term on-site monitoring, field experiments, remote sensing, and simulations have led to significant advances in our understanding of how plant diversity on the QTP has responded to climate change and human activity. This review synthesizes findings from previous researches on how climate change and human activity have impacted plant diversity on the QTP. We identify gaps in our knowledge and highlight the need for interdisciplinary studies, long-term monitoring networks, and adaptive management strategies to enhance our knowledge and safeguard the QTP's biodiversity amid accelerating global climate change.

Prunus spinulosa (2n = 4x = 32) is an evergreen species of significant medicinal usage and ecological value. However, the lacking of a high-quality genome of P. spinulosa has obstructed further exploration of its ecological study and phylogenetic relationship of Prunus. In this study, we present the first haplotype-resolved genome assembly of Prunus s.l. subgenus Laurocerasus, the tetraploid genome of P. spinulosa was phased into 32 pseudochromosomes with 4 haplotypes, the genome size of each haplotype ranged from 249.82 Mb to 259.69 Mb, and N50 fluctuated from 31.35 Mb to 33.25 Mb, the protein-coding genes vary from 21,272 to 22,668. Different evaluation methods showed that the P. spinulosa genome assembly has high quality of completeness, continuity and accuracy. Being the first complete genome of P. spinulosa, it provides a valuable genetic resource for the Prunus tetraploid species database and supports further functional genomic study of this species.

Complete plastid genomes have been proposed as potential "super-barcodes" for plant identification and delineation, particularly in cases where standard DNA barcodes may be insufficient. However, few studies have systematically addressed how taxonomic complexity, especially in rapidly radiating lineages with intricate evolutionary histories, might influence the efficacy of plastome-scale barcodes. Pedicularis is a hyperdiverse genus in the Himalaya-Hengduan Mountains, and previous studies have demonstrated high discriminatory power of the standard barcodes within this genus. Therefore, Pedicularis serves as a model for investigating the key plastome-sequence characteristics and biological phenomena that determine species-discrimination capacity. In this study, we evaluated 292 plastomes representing 96 Pedicularis species to compare the discriminatory power of complete plastid genomes with of standard DNA barcodes. Our results revealed that the traditional standard barcode combination (nrITS + matK + rbcL + trnH-psbA) achieved the highest discrimination rates (81.25%), closely followed by the plastid large single copy (LSC) region (80.21%), then by full plastome, the supermatrix of protein-coding genes, and hypervariable regions (79.17%). Notably, the matK and ycf1 gene alone could discriminate 78.13% of species. Key determinants of species discrimination by integrating alignment length (AL) and the proportion of parsimony-informative sites (PPIS), as well as conserved genes under relaxed selection exhibiting stronger discriminatory capacity. Unlike previous studies that demonstrated superior discrimination rates of plastome-scale barcodes, this study reveals a notable exception of minimal differences between traditional DNA and plastome-scale barcodes that appearing linked to Pedicularis' specific biological habits and potentially reflecting unique evolutionary patterns in the plastid genome.

•The first chromosome-level assembly for the Myristicaceae family.•Myristicaceae represents the earliest diverging families within the Magnoliales•Genomic constraints and climatic fluctuations may have contributed to the endangered status of Myristica yunnanensis.

Habitat fragmentation dramatically reshapes species richness and community composition. However, most estimates of β-diversity rely on incidence-based metrics, which consider only species presence/absence. Here, we introduce a novel framework that explicitly incorporates species abundance and intraspecific trait variation (ITV) into the quantification of taxonomic, functional, and phylogenetic β-diversity, allowing a more nuanced understanding of community differentiation. To demonstrate the utility of this framework, we quantified the effects of island area and isolation on β-diversity across plant communities in China's Thousand Island Lake. Abundance-weighted taxonomic multiple-site/pairwise β-diversity showed substantially higher nestedness and stronger nestedness-area relationship than incidence-based metrics, indicating that species-poor communities are not only subsets of richer ones but share similar abundance hierarchies, highlighting strong environmental filtering and hierarchical species sorting. We also found that the turnover component was less sensitive to isolation, suggesting limited dispersal effects. Incidence-based functional and phylogenetic distances increased with differences in island area, but these associations weakened or disappeared in abundance-weighted measures, suggesting stronger environmental filtering and functional/phylogenetic clustering among larger islands. Only abundance-weighted standardized effect sizes increased with island area differences. Additionally, ITV further amplified functional nestedness and buffered the influence of isolation on turnover, emphasizing its role in mitigating dispersal limitations. By jointly considering abundance and ITV, two often-overlooked but critical dimensions, this study advances our understanding of how fragmentation shapes β-diversity. These findings highlight the importance of integrating abundance-weighted and trait-based metrics into conservation strategies to better detect functionally important species, prioritize larger habitat patches, and design biodiversity monitoring that captures within-species variation.

•A chromosome-level genome of Amomum tsaoko (1.967 Gb, 93.9% completeness) provides an improved genomic resource.•Expanded terpene synthase families likely enhance medicinal terpenoid accumulation.•Population genomics reveals low genetic differentiation linked to historical domestication.•GWAS identifies zinc finger and AP2/EREBP genes significantly associated with fruit length.•Integrated multi-omics analyses highlight plant hormone regulators influencing fruit morphology.

Genetic information has been instrumental in elucidating the relationship between the East Asian Summer Monsoon (EASM) and subtropical evergreen broad-leaved forests (EBLFs). However, how the genomic insights of EBLFs' species correspond to environmental shifts induced by the EASM remains limited. In this study, we investigated the adaptive mechanisms of evergreen Engelhardia species in response to the EASM through genome sequencing and comparative genomic analyses from the de novo genome assemblies of five closely related Engelhardia taxa and one Rhoiptelea species. Our findings revealed that the divergence of evergreen trees from their sister deciduous species is closely associated with the onset and intensification of the EASM. This genomic transition may have coincided with a significant expansion of the terpene synthase (TPS) gene family in E. fenzelii, driven by four distinct modes of gene duplication. This expansion enhances the biosynthesis of terpene volatiles, providing a defensive mechanism against potential herbivory in EASM affected environments. We also identified a shared whole-genome duplication (WGD) event across Engelhardia, along with substantial differences in transposable element (TE) composition and activity, which contributed to genome size variation between E. fenzelii and E. roxburghiana. In addition, demographic analyses revealed a continuous population decline over the past 10 million years, further exacerbated by recent human disturbance, underscoring the conservation urgency for these species. These results not only provide preliminary insights into the complex evolutionary dynamics within the Engelhardia genus from genomic insights (e.g., the intricate relationships between genomic variations, environmental changes, and adaptive responses driven by significant climatic events such as the EASM), but also provides valuable insights into the conservation significance of EBLFs.

Species richness in any area results from the interplay of the processes of speciation, extinction, and dispersal. The relationships between species richness and climate should be considered as an outcome of the effects of climate on speciation, extinction, and dispersal. Diversification rate represents the balance of speciation and extinction rates over time. Here, I explore diversification rates in mosses across geographic and climatic gradients worldwide. Specifically, I investigate latitudinal patterns and climatic associations of the mean diversification rate of mosses at global, hemispheric, and smaller scales. I find that the mean diversification rate of mosses is positively correlated with species richness of mosses, increases with decreasing latitude and increasing mean annual temperature and annual precipitation, and is more strongly associated with mean annual temperature than with annual precipitation. These findings shed light on variation of species richness in mosses across the world. The negative relationship between species richness and latitude and the positive relationship between species richness and mean diversification rate in mosses suggest that higher moss species richness at lower latitudes might have resulted, at least to some degree, from higher moss diversification rates at lower latitudes.

Climate warming is reshaping the phenology of plants in recent decades, with potential implications for forest productivity, carbon sequestration, and ecosystem functioning. While the effects of warming on secondary growth phenology is becoming increasingly clear, the influence of environmental factors on different developmental phases of xylem remains to be quantified. In this study, we investigated the temporal dynamics of xylem cell enlargement, wall-thickening, and the interval between these events in twelve temperate tree species from Northeast China over the period 2019-2024. We found that both cell enlargement and wall-thickening advanced significantly in response to climate warming, with species-specific variations in the rate of advancement. Importantly, the advancing rate of wall-thickening was greater than that of cell enlargement, leading to a shortening of the interval between these two events. Linear mixed-effects models revealed that photoperiod, forcing temperature, and precipitation were the primary environmental drivers influencing the timing of both cell enlargement and wall-thickening, with photoperiod emerging as the most important factor. These results suggest that climate warming accelerates the heat accumulation required for the transition from xylem cell enlargement to wall-thickening, thereby shortening the time interval between these two developmental stages. Beyond contributing valuable multi-year xylem phenological data, our results provide mechanistic insights that enhance predictions of wood formation dynamics under future climate scenarios and improve the accuracy of forest carbon models.