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Summary The evolution of adjustable stomatal pores, enabling CO2 acquisition, was one of the most significant events in the development of life on land. Here, we investigate how the guard cell signalling pathways that regulate stomatal movements evolved. We compare fern and angiosperm guard cell transcriptomes and physiological responses, and examine the functionality of ion channels from diverse plant species. We find that, despite conserved expression in guard cells, fern anion channels from the SLAC/SLAH family are not activated by the same abscisic acid (ABA) pathways that provoke stomatal closure in angiosperms. Accordingly, we find an insensitivity of fern stomata to ABA. Moreover, our analysis points to a complex evolutionary history, featuring multiple gains and/or losses of SLAC activation mechanisms, as these channels were recruited to a role in stomatal closure. Our results show that the guard cells of flowering and nonflowering plants share similar core features, with lineage‐specific and ecological niche‐related adaptations, likely underlying differences in behaviour. [ABSTRACT FROM AUTHOR]

We expand the geographical distribution of 10 angiosperm species in Maranhão and Tocantins states. The species were collected during two field expeditions carried out by the Territorial Action Plan for the conservation of endangered species of the Meio Norte Territory between September 20 and 30, 2022 and between July 24 and 30, 2023, in both states. Photographs, comments on morphology and distribution-al data are provided for species of Acanthaceae, Aristolochiaceae, Euphorbiaceae, Myrtaceae, Orchidace-ae, Plantaginaceae, Pontederiaceae and Turneraceae.

Caffeic acid transferase (COMT) is a key enzyme in the lignin and melatonin synthesis pathways and plays an important role in plant growth and development. All seed plants have two characteristics: they have vascular tissues, phloem, and xylem, and they can produce and reproduce seeds. In order to understand the distribution and evolution of COMTs in seed plants, we performed physicochemical property analysis, subcellular localization, phylogenetic analysis, conserved motif analysis, and protein interaction network analysis of 44 COMT homologs from 26 seed plants through in silico. The results showed that in seed plants, the structure of COMT genes tends to be stable in different plant taxa, while the relationship between the chromosomal positions of different COMT genes in the same plant was more intricate. The conserved distribution of COMT in seed plants reflected its highly specialized function. [ABSTRACT FROM AUTHOR]

[ Objective ] From the aspect of species representativeness and diversity , the article aims to pro- vide evidence for plant diversity conservation and plant resource utilization in Qinghai area of the Kunlun Mountain National Park. [ Methods ] Based on field surveys , historical data , and literatures , we sorted out a list of seed plants in the assessment area and analyzed the composition , dominant taxa , geographic com- ponent , and endangered species of seed flora. [ Results ] ( 1 ) There was a total of 46 families , 146 genera , and 384 species of seed plants in Qinghai area of the Kunlun Mountain National Park , including 3 families , 3 genera , and 5 species of gymnosperms as well as 43 families , 143 genera , and 379 species of angio- sperms. The 4 families included Amaranthaceae , Asteraceae , Fabaceae and Poaceae occupy an important position in the seed flora of the assessed area , where monospecie and oligospecie constitute the main part of the family. ( 2 ) The dominant phenomenon of the seed plant family and genus was obvious in this area with 8 dominant families and 36 dominant genera , where 6 large genera had more than 10 species including Astragalus , Oxytropis , Artemisia , Saussurea , Poa , and Carex . ( 3 ) The areal-type of the families in this seed flora was mainly cosmopolitan , which was showing a temperate nature. The areal-type of genera was mainly temperate distribution with a close connection to the Laurasia. ( 4 ) There were 4 species of na- tional Grade Ⅱ protected wild plants , 8 species of Qinghai Province protected plants , and 6 species listed in “ China􀆴s Red List of Biodiversity ” . [ Conclusion ] The Qinghai area of the Kunlun National Park has di- verse geographical composition , but the endemic phenomenon is not obvious. The biodiversity is low. The floral composition shows the characteristics of arid to semi-arid transition and temperate to tropical transi- tion in the horizontal gradient.

Key message: The current status of molecular regulation of nitrogen assimilation and recent advances made in gymnosperms are reviewed. Gymnosperms are a heterogeneous and ancient group of seed plants that includes conifers, ginkgos, cycads and gnetophytes. Molecular studies on extant gymnosperms have been constrained by some discouraging features for experimental research such as their long life cycles, large sizes, complex megagenomes and abundant phenolic compounds in their woody tissues. However, the development of high-throughput sequencing and refined multiomics technologies in the last few years has allowed to explore the molecular basis of essential processes in this ancient lineage of plants. Nitrogen is one of the main limiting factors determining vascular development and biomass production in woody plants. Therefore, nitrogen uptake, metabolism, storage and recycling are essential processes for fundamental gymnosperm biology. Here, recent progress in the molecular regulation of nitrogen assimilation in gymnosperms is reviewed and some future perspectives on this topic are outlined. [ABSTRACT FROM AUTHOR]

Introduction: The Sanzenbacher Ranch deposit represents an early Permian plant assemblage in north-central Texas predominantly composed of pteridosperms, of which callipterids are dominant. This study investigates the interactions of a taxonomically broad range of plant hosts with insects, mites, and pathogens to assess the richness and frequency of damage. Methods: We used standard methods of the functional feeding group-damage type system and analyses graphically illustrated as nonmetric multidimensional scaling. Results: Of the total surface area represented, we quantified the fraction of the area herbivorized, providing a comparative perspective with regard to several similar studies of herbivory at nearby plant assemblages from the late Paleozoic. To assess insect herbivory, 1,361 plant specimens were analyzed, including fronds, leaves, reproductive structures, axes, and wood impressions. A total of 205 specimens presented one or more instances of insect herbivory (11.17%). Callipterid-peltasperms exhibited the highest number of interactions, with Autunia conferta, Rhachiphyllum schenkii, cf. Lodevia sp., cf. Comia sp., and an unidentified callipterid accounting for 49.34% of all interactions. Medullosans represented 10.53%, followed by lyginopterids with 8.55%. Forty-eight damage types (DTs) were recognized and classified into the nine functional feeding groups of hole feeding, margin feeding, surface feeding, piercing and sucking, oviposition, galling, seed predation, borings, and pathogens. Discussion: When compared to analogous late Paleozoic plant assemblages in Texas, Sanzenbacher Ranch exhibited almost all herbivore functional feeding groups, high richness of DTs, and low herbivory index of 0.26. This record shows high plant diversity in a seasonally dry environment that supports a trend of an early Permian increase in DT diversity in southwestern Euramerica. Sanzenbacher Ranch, different from other early Permian plant assemblages, sheds light on the dynamic ecological interactions of these ancient ecosystems. [ABSTRACT FROM AUTHOR]

Comprehensive biodiversity data is crucial for ecosystem protection. The Biome mobile app, launched in Japan, efficiently gathers species observations from the public using species identification algorithms and gamification elements. The app has amassed >6 million observations since 2019. Nonetheless, community-sourced data may exhibit spatial and taxonomic biases. Species distribution models (SDMs) estimate species distribution while accommodating such bias. Here, we investigated the quality of Biome data and its impact on SDM performance. Species identification accuracy exceeds 95% for birds, reptiles, mammals, and amphibians, but seed plants, molluscs, and fishes scored below 90%. Our SDMs for 132 terrestrial plants and animals across Japan revealed that incorporating Biome data into traditional survey data improved accuracy. For endangered species, traditional survey data required >2000 records for accurate models (Boyce index ≥ 0.9), while blending the two data sources reduced this to around 300. The uniform coverage of urban-natural gradients by Biome data, compared to traditional data biased towards natural areas, may explain this improvement. Combining multiple data sources better estimates species distributions, aiding in protected area designation and ecosystem service assessment. Establishing a platform for accumulating community-sourced distribution data will contribute to conserving and monitoring natural ecosystems.

Patterns of taxonomic and phylogenetic beta diversity and their relationships with environmental correlates can help reveal the origin and evolutionary history of regional biota. The Qinghai-Tibet Plateau (QTP) harbors an exceptionally diverse flora, however, a phylogenetic perspective has rarely been used to investigate its beta diversity and floristic regions. In this study, we used a phylogenetic approach to identify patterns of beta diversity and quantitatively delimit floristic regions on the Qinghai-Tibet Plateau. We also examined the relationships between multifaceted beta diversity, geographical distance, and climatic difference, and evaluated the relative importance of various factors (i.e., climate, topography and history) in shaping patterns of beta diversity. Sørensen dissimilarity indices indicated that patterns of species turnover among sites dominated the QTP. We also found that patterns of both taxonomic and phylogenetic beta diversity were significantly related to geographical distance and climatic difference. The environmental factors that contributed most to these patterns of beta diversity include annual precipitation, mean annual temperature, climatic gradients and climatic instability. Hierarchical dendrograms of dissimilarity and non-metric multidimensional scaling ordination based on phylogenetic beta diversity data identified ten floristic subregions in the QTP. Our results suggest that the contemporary environment and historical climate changes have filtered species composition among sites and eventually determined beta diversity patterns of plants in the QTP.

Differences in the number of alien plant species in different locations may reflect climatic and other controls that similarly affect native species and/or propagule pressure accompanied with delayed spread from the point of introduction. We set out to examine these alternatives for Himalayan plants, in a phylogenetic framework. We build a database of alien plant distributions for the Himalaya. Focusing on the well‐documented regions of Jammu & Kashmir (west) and Bhutan (east) we compare alien and native species for (1) richness patterns, (2) degree of phylogenetic clustering, (3) the extent to which species‐poor regions are subsets of species‐rich regions and (4) continental and climatic affinities/source. We document 1470 alien species (at least 600 naturalised), which comprise ~14% of the vascular plants known from the Himalaya. Alien plant species with tropical affinities decline in richness with elevation and species at high elevations form a subset of those at lower elevations, supporting location of introduction as an important driver of alien plant richness patterns. Separately, elevations which are especially rich in native plant species are also rich in alien plant species, suggesting an important role for climate (high productivity) in determining both native and alien richness. We find no support for the proposition that variance in human disturbance or numbers of native species correlate with alien distributions. Results imply an ongoing expansion of alien species from low elevation sources, some of which are highly invasive. Several reasons have been proposed for why alien species richness patterns vary across the globe, but they are rarely compared in a comprehensive test. Here we build a complete database of Himalayan alien plant species and show that both location of introduction and climate per se are likely important in explaining elevational and geographical patterns of species diversity. [ABSTRACT FROM AUTHOR]

IntroductionThe Sanzenbacher Ranch deposit represents an early Permian plant assemblage in north-central Texas predominantly composed of pteridosperms, of which callipterids are dominant. This study investigates the interactions of a taxonomically broad range of plant hosts with insects, mites, and pathogens to assess the richness and frequency of damage.MethodsWe used standard methods of the functional feeding group--damage type system and analyses graphically illustrated as nonmetric multidimensional scaling.ResultsOf the total surface area represented, we quantified the fraction of the area herbivorized, providing a comparative perspective with regard to several similar studies of herbivory at nearby plant assemblages from the late Paleozoic. To assess insect herbivory, 1,361 plant specimens were analyzed, including fronds, leaves, reproductive structures, axes, and wood impressions. A total of 205 specimens presented one or more instances of insect herbivory (11.17%). Callipterid-peltasperms exhibited the highest number of interactions, with Autunia conferta, Rhachiphyllum schenkii, cf. Lodevia sp., cf. Comia sp., and an unidentified callipterid accounting for 49.34% of all interactions. Medullosans represented 10.53%, followed by lyginopterids with 8.55%. Forty-eight damage types (DTs) were recognized and classified into the nine functional feeding groups of hole feeding, margin feeding, surface feeding, piercing and sucking, oviposition, galling, seed predation, borings, and pathogens.DiscussionWhen compared to analogous late Paleozoic plant assemblages in Texas, Sanzenbacher Ranch exhibited almost all herbivore functional feeding groups, high richness of DTs, and low herbivory index of 0.26. This record shows high plant diversity in a seasonally dry environment that supports a trend of an early Permian increase in DT diversity in southwestern Euramerica. Sanzenbacher Ranch, different from other early Permian plant assemblages, sheds light on the dynamic ecological interactions of these ancient ecosystems.

Abstract Differences in the number of alien plant species in different locations may reflect climatic and other controls that similarly affect native species and/or propagule pressure accompanied with delayed spread from the point of introduction. We set out to examine these alternatives for Himalayan plants, in a phylogenetic framework. We build a database of alien plant distributions for the Himalaya. Focusing on the well‐documented regions of Jammu & Kashmir (west) and Bhutan (east) we compare alien and native species for (1) richness patterns, (2) degree of phylogenetic clustering, (3) the extent to which species‐poor regions are subsets of species‐rich regions and (4) continental and climatic affinities/source. We document 1470 alien species (at least 600 naturalised), which comprise ~14% of the vascular plants known from the Himalaya. Alien plant species with tropical affinities decline in richness with elevation and species at high elevations form a subset of those at lower elevations, supporting location of introduction as an important driver of alien plant richness patterns. Separately, elevations which are especially rich in native plant species are also rich in alien plant species, suggesting an important role for climate (high productivity) in determining both native and alien richness. We find no support for the proposition that variance in human disturbance or numbers of native species correlate with alien distributions. Results imply an ongoing expansion of alien species from low elevation sources, some of which are highly invasive.

Summary: Regions harbouring high unique phylogenetic diversity (PD) are priority targets for conservation. Here, we analyse the global distribution of plant PD, which remains poorly understood despite plants being the foundation of most terrestrial habitats and key to human livelihoods.Capitalising on a recently completed, comprehensive global checklist of vascular plants, we identify hotspots of unique plant PD and test three hypotheses: (1) PD is more evenly distributed than species diversity; (2) areas of highest PD (often called 'hotspots') do not maximise cumulative PD; and (3) many biomes are needed to maximise cumulative PD.Our results support all three hypotheses: more than twice as many regions are required to cover 50% of global plant PD compared to 50% of species; regions that maximise cumulative PD substantially differ from the regions with outstanding individual PD; and while (sub‐)tropical moist forest regions dominate across PD hotspots, other forest types and open biomes are also essential.Safeguarding PD in the Anthropocene (including the protection of some comparatively species‐poor areas) is a global, increasingly recognised responsibility. Having highlighted countries with outstanding unique plant PD, further analyses are now required to fully understand the global distribution of plant PD and associated conservation imperatives across spatial scales. This article is part of the Special Collection 'Global plant diversity and distribution'. See https://www.newphytologist.org/global-plant-diversity for more details. [ABSTRACT FROM AUTHOR]

Floristic regions, conventionally established using species distribution patterns, have often overlooked the phylogenetic relationships among taxa. However, how phylogenetic relationships influence the historical interconnections within and among biogeographic regions remains inadequately understood. In this research, we compiled distribution data for seed plants in Gansu, a region of significant biogeographic diversity located in northwestern China.We proposed a novel framework for floristic regions within Gansu, integrating distribution data and phylogenetic relationships of genera-level native seed plants, aiming to explore the relationship between phylogenetic relatedness, taxonomic composition, and regional phylogenetic delineation. We found that (1) phylogenetic relatedness was strongly correlated with the taxonomic composition among floras in Gansu. (2) The southeastern Gansu region showed the lowest level of spatial turnover in both phylogenetic relationships and the taxonomic composition of floristic assemblages across the Gansu region. (3) Null model analyses indicated nonrandom phylogenetic structure across the region, where most areas showed higher phylogenetic turnover than expected given the underlying taxonomic composition between sites. (4) Our results demonstrated a consistent pattern across various regionalization schemes and highlighted the preference for employing the phylogenetic dissimilarity approach in biogeographical regionalization investigations. (5) Employing the phylogenetic dissimilarity approach, we identified nine distinct floristic regions in Gansu that are categorized into two broader geographical units, namely the northwest and southeast. (6) Based on the phylogenetic graphic regions of China across this area. [ABSTRACT FROM AUTHOR]

Premise: In recent years, Doyleales have played an important role in the discussion and exploration of seed plant relationships and the origin of angiosperms. This order comprises a diversity of recently described genera with cupule‐bearing compound ovulate cones recovered from Early Cretaceous deposits in North America and Asia. Their relatively late appearance in the fossil record, stratigraphically near the appearance of angiosperms in the Early Cretaceous, has been noteworthy. Here, we report a new genus of Doyleales, Zirabia gen. nov. from the Early Jurassic of Iran, that was originally described as the ginkgophyte Karkenia. Methods: We reinvestigated material previously assigned to Karkenia cylindrica from the Lower Jurassic of the Zirab locality, Alborz Mountains, northern Iran. Results: The studied specimen features a main axis bearing helically to irregularly arranged bract‐cupule complexes, each composed by a long laminar bract subtending and sheathing a cupule stalk that bears a single‐seeded cupule with a dorsal protrusion. The morphological features of this taxon do not conform with those of Karkenia, and suggest affinities with Doyleales rather than Ginkgoales. Within Doyleales, this fossil has a unique combination of characters indicating that it is a new genus within the order; thus, a new combination is erected, Zirabia cylindrica. Conclusions: Our results indicate that Doyleales is significantly older than previously thought, with their stratigraphic range now extending from the Lower Jurassic to the Cretaceous. The Early Jurassic occurrence of Doyleales provides important data on the emergence of seed‐enclosing structures seen in seed plants throughout the Mesozoic. [ABSTRACT FROM AUTHOR]

Using the method of on-the-spot sample transect lines and plots survey a comprehensive investigation on the seed plants in the Qialong provincial nature reserve was conducted. The research shows: ① The reserve had a total of 957 species from 480-genera and 132 families. of wild seed plants, including 5 species from 5. genera and 3. families of gymosperms and 952 species from 475. genera and 129 families of angiosperms. The Life-form spectrum showed that the number of woody plants was lower than that of herbaceous plants, the evergreen component of woody plants was lower than that of deciduous components, and the proportion of trees was significantly lower, showing obvious characteristics of restorative vegetation. The distribution types at families level were mainly distributed in the world (43) and pan- tropical distribution (38).The ratio (R/TD of tropical to temperate was about 1.78. At genus level, the main distribution types were pan-tropical distribution (104) and worldwide distribution (55) . the ratio (R/T) of tropical to temperate was a- bout 1.07 and the tropical nature was slightly dominant showing the characteristics of transition from tropical nature to temperate nature. Comparison with neighboring protected areas revealed that the flora in Qiaoling has unity with that of eastern China showed an obvious subtropical mountain characteristics. reflecting the basic feature of the flora of the monsoon region in eastern China as a whole. Furthermore the results also indicated that the low mountain and hilly terrain was more conducive to the growth of plants with tropical nature. [ABSTRACT FROM AUTHOR]

Leaf reflectance spectra have been increasingly used to assess plant diversity. However, we do not yet understand how spectra vary across the tree of life or how the evolution of leaf traits affects the differentiation of spectra among species and lineages. Here we describe a framework that integrates spectra with phylogenies and apply it to a global dataset of over 16 000 leaf-level spectra (400-2400 nm) for 544 seed plant species. We test for phylogenetic signal in spectra, evaluate their ability to classify lineages, and characterize their evolutionary dynamics. We show that phylogenetic signal is present in leaf spectra but that the spectral regions most strongly associated with the phylogeny vary among lineages. Despite among-lineage heterogeneity, broad plant groups, orders, and families can be identified from reflectance spectra. Evolutionary models also reveal that different spectral regions evolve at different rates and under different constraint levels, mirroring the evolution of their underlying traits. Leaf spectra capture the phylogenetic history of seed plants and the evolutionary dynamics of leaf chemistry and structure. Consequently, spectra have the potential to provide breakthrough assessments of leaf evolution and plant phylogenetic diversity at global scales.

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. Here, a total of 29 plant lineages, represented the main clades of seed plants and different habits, were selected to investigate the biotic interchange between tropical Asia and Australasia by integrated dated phylogenies, biogeography, and ancestral state reconstructions. Our statistics indicated that 68 migrations have occurred between tropical Asia and Australasia since the middle Eocene except terminal migrations, and the migration events from tropical Asia to Australasia is more than 2 times of the reverse. Only 12 migrations occurred before 15 Ma, whereas the remaining 56 migrations occurred after 15 Ma. Maximal number of potential dispersal events (MDE) analysis also shows obvious asymmetry, with southward migration as the main feature, and indicates the climax of bi-directional migrations occurred after 15 Ma. We speculate that the formation of island chains after the Australian–Sundaland collision and climate changes have driven seed plant migrations since the middle Miocene. Furthermore, biotic dispersal and stable habitat may be crucial for floristic interchange between tropical Asia and Australasia.

Summary: The Cycadales are an ancient and charismatic group of seed plants. However, their morphological evolution in deep time is poorly understood. While molecular divergence time analyses estimate a Cretaceous origin for most major living cycad clades, much of the extant diversity is inferred to be a result of Neogene diversifications. This leads to long branches throughout the cycadalean phylogeny that, with few exceptions, have yet to be rectified by unequivocal fossil cycads.We report a permineralized pollen cone from the Campanian Holz Shale located in Silverado Canyon, CA, USA (c. 80 million yr ago). This fossil was studied via serial sectioning, SEM, 3D reconstruction and phylogenetic analyses.Microsporophyll and pollen morphology indicate this cone is assignable to Skyttegaardia, a recently described genus based on disarticulated lignitized microsporophylls from the Early Cretaceous of Denmark. Data from this new species, including a simple cone architecture, anatomical details and vasculature organization, indicate cycadalean affinities for Skyttegaardia. Phylogenetic analyses support this assignment and recover Skyttegaardia as crown‐group Cycadales, nested within Zamiaceae.Our findings support a Cretaceous diversification for crown‐group Zamiaceae, which included the evolution of morphological divergent extinct taxa with unique traits that have yet to be widely identified in the fossil record. [ABSTRACT FROM AUTHOR]

The stem is one of the major organs in seed plants and is important for plant survival as well as in agriculture. However, due to the lack of clear external landmarks in many species, its developmental and evolutionary processes are understudied compared to other organs. Recent approaches tackling these problems, especially those focused on KNOX1 and BLH transcription factors belonging to the TALE homeodomain superfamily have started unveiling the patterning process of nodes and internodes by connecting previously accumulated knowledge on lateral organ regulators. Fossil records played crucial roles in understanding the evolutionary process of the stem. The aim of this review is to introduce how the stem evolved from ancestorial sporophyte axes and to provide frameworks for future efforts in understanding the developmental process of this elusive but pivotal organ. [ABSTRACT FROM AUTHOR]

Large-scale patterns of biodiversity and the underlying mechanisms that regulate these patterns are central topics in biogeography and macroecology. The Qinghai-Tibet Plateau serves as a natural laboratory for studying these issues. However, most previous studies have focused on the entire Qinghai-Tibet Plateau, leaving independent physical geographic subunits in the region less well understood. We studied the current plant diversity of the Kunlun Mountains, an independent physical geographic subunit located in northwestern China on the northern edge of the Qinghai-Tibet Plateau. We integrated measures of species distribution, geological history, and phylogeography, and analyzed the taxonomic richness, phylogenetic diversity, and community phylogenetic structure of the current plant diversity in the area. The distribution patterns of 1911 seed plants showed that species were distributed mainly in the eastern regions of the Kunlun Mountains. The taxonomic richness, phylogenetic diversity, and genera richness showed that the eastern regions of the Kunlun Mountains should be the priority area of biodiversity conservation, particularly the southeastern regions. The proportion of Chinese endemic species inhabiting the Kunlun Mountains and their floristic similarity may indicate that the current patterns of species diversity were favored via species colonization. The Hengduan Mountains, a biodiversity hotspot, is likely the largest source of species colonization of the Kunlun Mountains after the Quaternary. The net relatedness index indicated that 20 of the 28 communities examined were phylogenetically dispersed, while the remaining communities were phylogenetically clustered. The nearest taxon index indicated that 27 of the 28 communities were phylogenetically clustered. These results suggest that species colonization and habitat filtering may have contributed to the current plant diversity of the Kunlun Mountains via ecological and evolutionary processes, and habitat filtering may play an important role in this ecological process.

The Gnetales are one of the most fascinating groups within seed plants. Although the advent of molecular phylogenetics has generated some confidence in their phylogenetic placement of Gnetales within seed plants, their macroevolutionary history still presents many unknowns. Here, we review the reasons for such unknowns, and we focus the discussion on the presence of “long branches” both in their molecular and morphological history. The increased rate of molecular evolution and genome instability as well as the numerous unique traits (both reproductive and vegetative) in the Gnetales have been obstacles to a better understanding of their evolution. Moreover, the fossil record of the Gnetales, though relatively rich, has not yet been properly reviewed and investigated using a phylogenetic framework. Despite these apparent blocks to progress we identify new avenues to enable us to move forward. We suggest that a consilience approach, involving different disciplines such as developmental genetics, paleobotany, molecular phylogenetics, and traditional anatomy and morphology might help to “break” these long branches, leading to a deeper understanding of this mysterious group of plants.

Floristic regions, conventionally established using species distribution patterns, have often overlooked the phylogenetic relationships among taxa. However, how phylogenetic relationships influence the historical interconnections within and among biogeographic regions remains inadequately understood. In this research, we compiled distribution data for seed plants in Gansu, a region of significant biogeographic diversity located in northwestern China.We proposed a novel framework for floristic regions within Gansu, integrating distribution data and phylogenetic relationships of genera-level native seed plants, aiming to explore the relationship between phylogenetic relatedness, taxonomic composition, and regional phylogenetic delineation. We found that (1) phylogenetic relatedness was strongly correlated with the taxonomic composition among floras in Gansu. (2) The southeastern Gansu region showed the lowest level of spatial turnover in both phylogenetic relationships and the taxonomic composition of floristic assemblages across the Gansu region. (3) Null model analyses indicated nonrandom phylogenetic structure across the region, where most areas showed higher phylogenetic turnover than expected given the underlying taxonomic composition between sites. (4) Our results demonstrated a consistent pattern across various regionalization schemes and highlighted the preference for employing the phylogenetic dissimilarity approach in biogeographical regionalization investigations. (5) Employing the phylogenetic dissimilarity approach, we identified nine distinct floristic regions in Gansu that are categorized into two broader geographical units, namely the northwest and southeast. (6) Based on the phylogenetic graphic regions of China across this area.

Understanding patterns of species richness along an altitudinal gradient is one of the central focuses of ecological research and can offer us insights into the mechanisms of species diversity. However, few studies have focused on a large scale. Based on the distribution data of 3538 species collected from the local flora of the entire Qinling Mountains, the patterns of seed plant richness along the altitude were analyzed; three hypotheses proposed to explain the pattern were tested, and five methods verifying the applicability of Rapoport's rule were examined. The results of the research were as follows: species richness of seed plants along an altitudinal gradient in the Qinling Mountains displayed a single peak, occurring at 1000–1500 m (R2 = 0.67, p < 0.001), and similar patterns were also observed at the genus and family level; The proportion and density of endemic species were increased monotonously with altitude; the altitudinal patterns of species richness in the Qinling Mountains were not fully explained by a single hypothesis such as species area relationship (SAR), mid-domain effect (MDE) and ecological metabolism theory (MTE), while the interpretation amount of SAR and MDE was 80.4%, indicating that area and mid-domain effect significantly affect the patterns of plant species richness in the Qinling Mountains; only the Pagel upper-bound method supported Rapoport's rule. However, all species were grouped according to their altitude distribution; most of results of the species-by-species method, Rohde midpoint method, and Stevens method conformed to Rapoport's rule. The test of Rapoport's rule is obviously affected by the test method, so more advanced and universal methods are expected to be developed in future. [ABSTRACT FROM AUTHOR]

SUMMARY: The exocyst complex is an octameric evolutionarily conserved tethering complex engaged in the regulation of polarized secretion in eukaryotic cells. Here, we focus on the systematic comparison of two isoforms of the SEC15 exocyst subunit, SEC15a and SEC15b. We infer that SEC15 gene duplication and diversification occurred in the common ancestor of seed plants (Spermatophytes). In Arabidopsis, SEC15a represents the main SEC15 isoform in the male gametophyte, and localizes to the pollen tube tip at the plasma membrane. Although pollen tubes of sec15a mutants are impaired, sporophytes show no phenotypic deviations. Conversely, SEC15b is the dominant isoform in the sporophyte and localizes to the plasma membrane in root and leaf cells. Loss‐of‐function sec15b mutants exhibit retarded elongation of hypocotyls and root hairs, a loss of apical dominance, dwarfed plant stature and reduced seed coat mucilage formation. Surprisingly, the sec15b mutants also exhibit compromised pollen tube elongation in vitro, despite its very low expression in pollen, suggesting a non‐redundant role for the SEC15b isoform there. In pollen tubes, SEC15b localizes to distinct cytoplasmic structures. Reciprocally to this, SEC15a also functions in the sporophyte, where it accumulates at plasmodesmata. Importantly, although overexpressed SEC15a could fully complement the sec15b phenotypic deviations in the sporophyte, the pollen‐specific overexpression of SEC15b was unable to fully compensate for the loss of SEC15a function in pollen. We conclude that the SEC15a and SEC15b isoforms evolved in seed plants, with SEC15a functioning mostly in pollen and SEC15b functioning mostly in the sporophyte. Significance Statement: The functional differentiation of two isoforms of the anciently duplicated and diverged (in seed plants) SEC15 exocyst subunit is manifest by their differential expression between the sporophyte and male gametophyte, distinct subcellular localization and phenotypic devations in Arabidopsis. Although SEC15a is crucial for pollen tube elongation, it also acquired specific functions in the sporophyte. Conversely, SEC15b is essential for sporophyte morphogenesis but also contributes to pollen tube elongation. Gene expression data indicate that this split of functions is conserved within Angiosperms. [ABSTRACT FROM AUTHOR]

There is a paradox in the plant mitochondrial genome, that is, the genic region evolves slowly while the intergenic region evolves rapidly. Thus, the intergenic regions of the plant mitochondrial genome are difficult to align across different species, even in closely related species. Here, to character the mechanism of this paradox, we identified interspecific variations in the Ginkgo biloba, Oryza sativa, and Arabidopsis thaliana mitochondrial and plastid genome at a genome-wide level. The substitution rate of synonymous sites in genic regions was similar to the substitution rate of intergenic regions, while the substitution rate of nonsynonymous sites in genic regions was lower than that in intergenic regions, suggesting the mutation inputs were the same among different categories within the organelle genome, but the selection pressure varied. The substitution rate of single-copy regions was higher than that of IR (inverted repeats) in the plastid genome at an intraspecific level. The substitution rate of single-copy regions was higher than that of repeats in the G. biloba and A. thaliana mitochondrial genomes, but lower in that of O. sativa. This difference may be related to the length and distribution of repeats. Copy number variations that existed in the G. biloba and O. sativa mitochondrial genomes were confirmed. This study reveals the intraspecific variation pattern of organelle genomes at a genome-wide level, and that copy number variations were common in plant mitochondrial genomes. [ABSTRACT FROM AUTHOR]

The earliest ovules in the Late Devonian (Famennian) are surrounded by a cupule that is involved in both protection and pollination, and generally have free integumentary lobes. Here we report a new taxon from the Famennian of China, Guazia dongzhiensis gen. et sp. nov. The terminally borne ovule is apparently acupulate (without cupule) and has four radially arranged wing-like integumentary lobes that are extensively fused, and folded lengthwise and inwards. Guazia provides evidence that not all Devonian seeds possess a cupule and it increases their diversity in integumentary lobes. This genus also suggests that the integuments develop new functions, probably including wind dispersal at the expense of the cupules. [ABSTRACT FROM AUTHOR]

Niche filtering predicts that abundant species in communities have similar traits that are suitable for the environment. However, niche filtering can operate on distinct axes of trait variation in response to different ecological conditions. Here, we use a trait‐based approach to infer niche filtering processes and (a) test if abundant and rare species in grassland communities are differently positioned along distinct axes of trait variation, (b) determine if these trait variation axes, as well as phylogenetic and functional similarities, drive species relative abundance (above‐ground cover) within communities, and (c) explore whether these relationships vary across grassland types and macro‐climatic gradients.We analysed species abundance in vegetation plots from temperate grasslands in Central Europe as a function of species position along three axes of trait variation: the 'Plant Size Spectrum' (PSS), the 'Leaf Economics Spectrum' (LES) and the 'Life span/Clonality Spectrum' (LCS). We also used phylogenetic and functional similarities in the multi‐dimensional trait space as predictors of species abundance. We compared our results among alpine, wet, mesic and dry grasslands and tested whether the effect of the predictors on species abundance was significant across macro‐climatic gradients.Compared to abundant species, rare species in grassland communities were more commonly annual and non‐clonal, had lower stature and smaller leaves and seeds, and relied on more acquisitive leaf economics. Our predictors significantly explained species abundance in approximately one‐third of the plots. LES was the most important predictor across all plots, with the most prominent effect in alpine and dry grasslands and areas with more extreme temperatures. In contrast, in mesic and wet grasslands and grasslands located in warmer and less seasonal regions, species abundance was best predicted by phylogenetic similarities between species, with Poaceae species becoming more abundant.Our study explored trait–abundance relationships for different community types across a large area and broad macro‐climatic gradients. We conclude that niche filtering, and particularly resource‐acquisition trade‐offs, drives species abundance in temperate grassland communities of Central Europe. Our findings emphasize the interaction between local environmental conditions and plant function in determining community assembly. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Large‐scale patterns of biodiversity and formation have garnered increasing attention in biogeography and macroecology. The Qinghai‐Tibet Plateau (QTP) is an ideal area for exploring these issues. However, the QTP consists of multiple geographic subunits, which are understudied. The Kunlun Mountains is a geographical subunit situated in the northern edge of the QTP, in northwest China. The diversity pattern, community phylogenetic structures, and biogeographical roles of the current flora of the Kunlun Mountains were analyzed by collecting and integrating plant distribution, regional geological evolution, and phylogeography. A total of 1911 species, 397 genera, and 75 families present on the Kunlun Mountains, of which 29.8% of the seed plants were endemic to China. The mean divergence time (MDT) of the Kunlun Mountains flora was in the early Miocene (19.40 Ma). Analysis of plant diversity and MDT indicated that the eastern regions of the Kunlun Mountains were the center of species richness, endemic taxa, and ancient taxa. Geographical origins analysis showed that the Kunlun Mountains flora was diverse and that numerous clades were from East Asia and Tethyan. Analysis of geographical origins and geological history together highlighted that the extant biodiversity on the Kunlun Mountains appeared through species recolonization after climatic fluctuations and glaciations during the Quaternary. The nearest taxon index speculated that habitat filtering was the most important driving force for biodiversity patterns. These results suggest that the biogeographical roles of the Kunlun Mountains are corridor and sink, and the corresponding key processes are species extinction and immigration. The Kunlun Mountains also form a barrier, representing a boundary among multiple floras, and convert the Qinghai‐Tibet Plateau into a relatively closed geographical unit. [ABSTRACT FROM AUTHOR]

Comprehensive biodiversity data is crucial for ecosystem protection. The Biome mobile app, launched in Japan, efficiently gathers species observations from the public using species identification algorithms and gamification elements. The app has amassed >6 million observations since 2019. Nonetheless, community-sourced data may exhibit spatial and taxonomic biases. Species distribution models (SDMs) estimate species distribution while accommodating such bias. Here, we investigated the quality of Biome data and its impact on SDM performance. Species identification accuracy exceeds 95% for birds, reptiles, mammals, and amphibians, but seed plants, molluscs, and fishes scored below 90%. Our SDMs for 132 terrestrial plants and animals across Japan revealed that incorporating Biome data into traditional survey data improved accuracy. For endangered species, traditional survey data required >2000 records for accurate models (Boyce index ≥ 0.9), while blending the two data sources reduced this to around 300. The uniform coverage of urban-natural gradients by Biome data, compared to traditional data biased towards natural areas, may explain this improvement. Combining multiple data sources better estimates species distributions, aiding in protected area designation and ecosystem service assessment. Establishing a platform for accumulating community-sourced distribution data will contribute to conserving and monitoring natural ecosystems., Competing Interests: KA, YN Employed by Biome Inc, but not financially benefit directly from the publication of this paper, MU, HN No competing interests declared, TG CTO of Biome Inc, and an inventor of the species-identification-AI-algorithm JPN patents 6590417 and US patents 11048969, but not financially benefit directly from the publication of this paper, SF CEO of Biome Inc, and an inventor of the species-identification-AI-algorithm JPN patents 6590417 and US patents 11048969, but not financially benefit directly from the publication of this paper, (© 2024, Atsumi et al.)

Summary: Identifying the contours and correlates of species turnover is central to understanding the nature of biogeographical regions. The Hengduan Mountains region of south‐central China (HMR) is well known for its high diversity of plants, but its boundaries and internal floristic structure are poorly understood, especially in relation to geographical and environmental factors.With data on occurrences and elevational ranges of seed plants across the HMR and adjacent areas of the greater Qinghai‐Tibet Plateau, we identified motifs (distinct species assemblages) by Grade of Membership models, and characterized relative contributions of geography, elevation, and climate to their spatial patterns.Motifs segregate primarily by latitude, elevation, and correlated environmental variables, most sharply across the tropical‐temperate divide. Secondarily, they segregate by longitude and geographical features, and reveal a novel divide across the Jinsha River. A core set of motifs corresponds to previous delineations of the HMR.The HMR biodiversity hotspot is more a mosaic of floristic elements than a cohesive entity. Grade of Membership models effectively reveal the geographical contours of biotic structure, and are a valuable new tool for biogeographical analysis. See also the Commentary on this article by Muellner‐Riehl & Favre, 232: 964–966. [ABSTRACT FROM AUTHOR]

Pulau Aur is located in the South China Sea ca. 74 km east of Mersing, Johor. The terrain of Pulau Aur, which covers an area of ca. 19 km2, is almost entirely composed of granite rocks and several short beaches providing a unique diversity of flora on the island. A study of flora that focuses on the species of seed plants mainly trees has identified as many as 135 species belonging to 104 genera and 47 families in the primary, regenerated, secondary forests and sandy coastal vegetation. It is hoped that the information from the specimens collected and recorded can be used as a reference and help other researchers as well as stakeholders in ecotourism management and forest conservation plan. [ABSTRACT FROM AUTHOR]

Understanding patterns of species richness along an altitudinal gradient is one of the central focuses of ecological research and can offer us insights into the mechanisms of species diversity. However, few studies have focused on a large scale. Based on the distribution data of 3538 species collected from the local flora of the entire Qinling Mountains, the patterns of seed plant richness along the altitude were analyzed; three hypotheses proposed to explain the pattern were tested, and five methods verifying the applicability of Rapoport’s rule were examined. The results of the research were as follows: species richness of seed plants along an altitudinal gradient in the Qinling Mountains displayed a single peak, occurring at 1000–1500 m (R2 = 0.67, p < 0.001), and similar patterns were also observed at the genus and family level; The proportion and density of endemic species were increased monotonously with altitude; the altitudinal patterns of species richness in the Qinling Mountains were not fully explained by a single hypothesis such as species area relationship (SAR), mid-domain effect (MDE) and ecological metabolism theory (MTE), while the interpretation amount of SAR and MDE was 80.4%, indicating that area and mid-domain effect significantly affect the patterns of plant species richness in the Qinling Mountains; only the Pagel upper-bound method supported Rapoport’s rule. However, all species were grouped according to their altitude distribution; most of results of the species-by-species method, Rohde midpoint method, and Stevens method conformed to Rapoport’s rule. The test of Rapoport’s rule is obviously affected by the test method, so more advanced and universal methods are expected to be developed in future.

Onions - a valuable vegetable. Despite the significant production volumes of this crop in our country (800 thousand tons), they do not fully satisfy the needs of the market. An effective method of increasing the production of vegetables is the variety renewal. But the introduction of new varieties in the production is impossible without the presence of seeds. An effective method of increasing the yield of seeds is fertilizers. Thanks to their use, crop yields can be increased by 30 - 50%. The aim of the research was to study the effect of doses and methods of fertilizer application on the growth, development and productivity of seed plants, yield and seed quality of onion variety Lyubchik against the background of irrigation with sprinkling in the conditions of the northern Steppe of Ukraine. Bookmark and conduct field and laboratory experiments conducted in accordance with existing generally accepted and standardized methods. According to the results of biometric observations, it was found that the use of fertilizers provided an increase in the number and height of leaves during the phase of the beginning of the regrowth of flowering arrows. It is noted that the number of leaves increased from 8.4 pcs. to control up to 10.7 pcs. on the standard (N90P135K90) and 11.5 pcs. when making N30P45K30 + Reakom 2×3 l/ha. The height of the rosette of leaves in the experiment was 35.2 cm at the control and 36.6 - 37.1 cm, respectively, on the fertilized variants. Measurements made during the beginning of flowering established a tendency for the height and number of arrows to increase, as well as a significant increase in the diameter of the inflorescence of onions by 20.8 - 37.5% to 5.8 - 6.6 cm (control - 4.8 cm). Improving the habit of plants had a positive effect on their seed productivity. The application of P45K30 locally + 2 top dressing N15 + 2 foliar top dressing with Reakom 3 l/ha provided the highest seed productivity in the experiment - 26.8 g, which was significantly higher compared to the control (without fertilizers - 22.4 g). Accordingly, this version of the fertilizer provided the highest seed yield - 430 kg/ha. Qualitative indicators of seeds met the requirements of the current state standard and were.

Background and Aims An arbuscular mycorrhiza is a mutualistic symbiosis with plants as carbon providers for fungi. However, achlorophyllous arbuscular mycorrhizal species are known to obtain carbon from fungi, i.e. they are mycoheterotrophic. These species all have the Paris type of arbuscular mycorrhiza. Recently, two chlorophyllous Paris -type species proved to be partially mycoheterotrophic. In this study, we explore the frequency of this condition and its association with Paris -type arbuscular mycorrhiza. Methods We searched for evidence of mycoheterotrophy in all currently published 13C, 2H and 15N stable isotope abundance patterns suited for calculations of enrichment factors, i.e. isotopic differences between neighbouring Paris - and Arum -type species. We found suitable data for 135 plant species classified into the two arbuscular mycorrhizal morphotypes. Key Results About half of the chlorophyllous Paris -type species tested were significantly enriched in 13C and often also enriched in 2H and 15N, compared with co-occurring Arum -type species. Based on a two-source linear mixing model, the carbon gain from the fungal source ranged between 7 and 93 % with ferns > horsetails > seed plants. The seed plants represented 13 families, many without a previous record of mycoheterotrophy. The 13C-enriched chlorophyllous Paris -type species were exclusively herbaceous perennials, with a majority of them thriving on shady forest ground. Conclusions Significant carbon acquisition from fungi appears quite common and widespread among Paris -type species, this arbuscular mycorrhizal morphotype probably being a pre-condition for developing varying degrees of mycoheterotrophy. [ABSTRACT FROM AUTHOR]

To evaluate the phylogenetic patterns of the distribution and evolution of plant secondary metabolites (PSMs), we selected 8 classes of PSMs and mapped them onto an updated phylogenetic tree including 437 families of seed plants. A significant phylogenetic signal was detected in 17 of the 18 tested seed-plant clades for at least 1 of the 8 PSM classes using the D statistic. The phylogenetic signal, nevertheless, indicated weak clustering of PSMs compared to a random distribution across all seed plants. The observed signal suggests strong diversifying selection during seed-plant evolution and/or relatively weak evolutionary constraints on the evolution of PSMs. In the survey of the current phylogenetic distributions of PSMs, we found that multiple origins of PSM biosynthesis due to external selective forces for diverse genetic pathways may have played important roles. In contrast, a single origin of PSMs seems rather uncommon. The distribution patterns for PSMs observed in this study may also be useful in the search for natural compounds for medicinal purposes. [ABSTRACT FROM AUTHOR]

Sporopollenin is a highly resistant biopolymer that forms the outer wall of pollen and spores (sporomorphs). Recent research into sporopollenin chemistry has opened up a range of new avenues for palynological research, including chemotaxonomic classification of morphologically cryptic taxa. However, there have been limited attempts to directly integrate extant and fossil sporopollenin chemical data. Of particular importance is the impact of sample processing to isolate sporopollenin from fresh sporomorphs, and the extent of chemical changes that occur once sporomorphs enter the geological record. Here, we explore these issues using Fourier transform infrared (FTIR) microspectroscopy data from extant and fossil grass, Nitraria (a steppe plant), and conifer pollen. We show a 98% classification success rate at subfamily level with extant grass pollen, demonstrating a strong taxonomic signature in isolated sporopollenin. However, we also reveal substantial chemical differences between extant and fossil sporopollenin, which can be tied to both early diagenetic changes acting on the sporomorphs and chemical derivates of sample processing. Our results demonstrate that directly integrating extant and late Quaternary chemical data should be tractable as long as comparable sample processing routines are maintained. Consistent differences between extant and deeper time sporomorphs, however, suggests that classifying fossil specimens using extant training sets will be challenging. Further work is therefore required to understand and simulate the effects of diagenetic processes on sporopollenin chemistry. [ABSTRACT FROM AUTHOR]

Gibberellins (GAs) are a major class of plant hormones that regulates diverse developmental programs. Both acquiring abilities to synthesize GAs and evolving divergent GA receptors have been demonstrated to play critical roles in the evolution of land plants. In contrast, little is understood regarding the role of GA‐inactivating mechanisms in plant evolution. Here we report on the origin and evolution of GA methyltransferases (GAMTs), enzymes that deactivate GAs by converting bioactive GAs to inactive GA methylesters. Prior to this study, GAMT genes, which belong to the SABATH family, were known only from Arabidopsis. Through systematic searches for SABATH genes in the genomes of 260 sequenced land plants and phylogenetic analyses, we have identified a putative GAMT clade specific to seed plants. We have further demonstrated that both gymnosperm and angiosperm representatives of this clade encode active methyltransferases for GA methylation, indicating that they are functional orthologs of GAMT. In seven selected seed plants, GAMT genes were mainly expressed in flowers and/or seeds, indicating a conserved biological role in reproduction. GAMT genes are represented by a single copy in most species, if present, but multiple copies mainly produced by whole genome duplications have been retained in Brassicaceae. Surprisingly, more than 2/3 of the 248 flowering plants examined here lack GAMT genes, including all species of Poales (e.g., grasses), Fabales (legumes), and the large Superasterid clade of eudicots. With these observations, we discuss the significance of GAMT origination, functional conservation and diversification, and frequent loss during the evolution of flowering plants. [ABSTRACT FROM AUTHOR]

To explore the pattern of species richness along with the altitudinal gradient in the Jiaozi Snow Mountain, species richness, Shannon index, and Bray - curtis index were used to quantify taxonomic alpha diversity and beta diversity. Then these indices were related to annual mean temperature, annual mean recipitation, slope, aspect, lithology and soil type by applying multiple regression on distance matrices ( MRM) and variance partition. The results showed that: (1) The species richness increased rapidly at the first and then decreased with increasing elevation, peaking about at 3 000 m while another 2 small peaks at 3 500 m and 3 900 m; (2) Annual mean temperature, annual mean precipitation, rock and soil types were significantly related to Shannon index. The 85% of variation in the alpha diversity can be explained by the composed of soil, slope and aspect; 3All the environmental factors were significantly related to beta diversity. The three factors of rock type, annual average rainfall and annual average temperature were particularly significant. The 90% of variance in the beta diversity can be explained by annual average precipitation differences and rock type differences. The results highlighted the combinational effect of the climate, soil and topography to the seed plant diversity in Jiaozi Snow Mountains, so the niche process made a great effect to the community species composition in this area. [ABSTRACT FROM AUTHOR]

Background: Species density along elevation gradients often shows hump-shaped patterns, but in-depth data for Myanmar is still not available. Aim: The first plot-based study to detect the elevational patterns of life forms and tree leaf traits, and their relation to environmental factors in Myanmar. Methods: All seed plant species were recorded on 76 plots between 400 and 4100 m. Regression models were used to identify the variables with highest predictive power for species densities of different life forms and leaf traits. Results: Species density showed a linear elevational decline except for grasses (increase) and epiphytes (hump-shaped pattern) and were related to temperature and precipitation in all considered life forms. Tree leaf size, the proportion of species with simple leaves and leaves with drip tips decreased with elevation, while the proportion of toothed leaves increased. Conclusions: Our data partly confirm some widely held assumptions about elevation patterns in species density and leaf traits. While the climatic dependence behaves as expected, leaf traits and lifeforms show mixed and sometimes surprising patterns. Previous knowledge of these patterns is partly confirming, but highly scattered regionally, so our study performed in one region offers a rare opportunity towards a natural history image of a biodiversity hotspot.. [ABSTRACT FROM AUTHOR]

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RNA Directed DNA Methylation (RdDM) is a pathway that mediates de novo DNA methylation, an evolutionary conserved chemical modification of cytosine bases, which exists in living organisms and utilizes small interfering RNA. Plants utilize DNA methylation for transposable element (TE) repression, regulation of gene expression and developmental regulation. TE activity strongly influences genome size and evolution, therefore making DNA methylation a key component in understanding divergence in genome evolution among seed plants. Multiple proteins that have extensively been studied in model plant Arabidopsis thaliana catalyze RNA dependent DNA Methylation pathway along with small interfering RNA. Several developmental functions have also been attributed to DNA methylation. This review will highlight aspects of RdDM pathway dynamics, evolution and functions in seed plants with focus on recent findings on conserved and non-conserved attributes between angiosperms and gymnosperms to potentially explain how methylation has impacted variations in evolutionary and developmental complexity among them and advance current understanding of this crucial epigenetic pathway. [ABSTRACT FROM AUTHOR]

North America is a large continent with extensive climatic, geological, soil, and biological diversity. As biota faces threat from habitat destruction and climate change, making a quantitative assessment of biodiversity becomes critically important. Rapid digitization of plant specimen records and accumulation of DNA sequence data enable a much‐needed broad synthesis of species occurrences with phylogenetic data. In this study, the first such synthesis of a flora from such a large and diverse part of the world is attempted, all seed plants from the North American continent (here defined to include Canada, United States, and Mexico), with a focus on examining phylogenetic diversity and endemism. We collected digitized plant specimen records and chose a coarse grain for analysis, recognizing that this grain is currently necessary for reasonable completeness per sampling unit. We found that raw richness and endemism patterns largely support previous hypotheses of biodiversity hotspots. The application of phylogenetic metrics and a randomization test revealed novel results, including a significant phylogenetic clustering across the continent, a striking east–west geographical difference in the distribution of branch lengths, and the discovery of centers of neo‐ and paleoendemism in Mexico, the southwestern USA, and the southeastern USA. Finally, our examination of phylogenetic beta diversity provides a new approach to compare centers of endemism. We discuss the empirical challenges of working at the continental scale and the need for more sampling across large parts of the continent, for both DNA data for terminal taxa and spatial data for poorly understood regions, to confirm and extend these results. [ABSTRACT FROM AUTHOR]

Asian countries are experiencing severe biodiversity loss, so it is crucial to develop practical conservation actions and strategies. Threats to species are often dynamic, as their impacts on extinction risk change over time. There is an urgent need to better understand how these factors are interrelated and how they vary spatially with extinction risk. Here, we presented a spatially explicit method to evaluate the dynamic trends and predictors of seed plants' extinction risks across countries, using National Red List data from China, Japan, and Sri Lanka as case studies, by calculating the Red List Index (RLI) and mapping the percentage of seed plants facing increasing risks and pressures. We found overall decrease in extinction risks, however, a substantial number of species, ranging from 328 to 1343 depending on the country, still showed increasing extinction risks. Increasing extinction risks of plants was strongly correlated with changes in threats, such as urban expansion, temperature changes, and tree canopy cover changes, rather than static threat intensity. Specifically, increasing tree canopy cover significantly associated with plant extinction risks in both China and Sri Lanka, where large-scale afforestation and economic forest plantation probably resulted in habitat degradation and species loss. Concerningly, our findings indicated that land-use change was the dominant driver of increased species extinction risk in these two countries, in contrast to climate change in Japan. As governments commit to the Kunming-Montreal Global Biodiversity Framework, we suggest them to make site-specific or taxa-specific policies to ensure the effectively prevention of biodiversity loss. [ABSTRACT FROM AUTHOR]

The results of research work on carrot seed growing through wintering seedlings carried out at laboratory of seed studies and seed production of Transnistrian Research Institute of Agriculture, on the soil of the first terrace at the rive Dniester were presented in the article. Seed bearing plants of garden carrot ‘Krasavka’ were the object of the study. The seeds were sown to produce the seedlings on 15-16 August. In the first decade of December the plants were covered with white agrotextile with density 23g/m2 that was removed at the beginning of April. The proportion of plant that passed the winter depending on a year of cultivation was 95-100% under argotextile, and 50-80% in open plot. The plants under agrotextile reached 28 cm a high and had 5-7 well-developed leaves, while those on the open plot were at phase of active foliage growing about 10-13 cm. long. Thus, for early mechanized planting in optimal terms the wintering seedlings grown under agrotextile had the best biometrical characteristics. Moreover the outcome of carrot seedlings was 1.2-1.25 million per hectare. Such quantity of seedlings was sufficient to plant 9-10 ha of carrot plants, where the coefficient of multiplication reached 9-10, and only 3 when growing seeds through mother plant as biennial culture. Viability of seed plants grown through seedlings was 100%. Losses of plant with weight 120-150 grams from damage caused by diseases was 23%. The seed yield, when growing seedlings was 639 kg/ha, but growing through plants was 332 kg/ha. The seed outcome suitable for precise mechanized sowing through seedling growing was 77%, where seed germination was 90%, with seed fraction 1.51 and >2.0 mm. It was essentially improved their yielding characteristics. Seed outcome from this fraction obtained through planting method was 32%. The proportion of seeds in fraction 1-1.5 mm was 68%. For mechanized single-seed sowing, the seeds can be used only after mini-coating. The seed growing from wintering seedlings fully excluded the application of fungicides for plant protection and seedlings from diseases; there are no expenses for building the expensive storage facilities needed for mother plant storing.

Species assemble into communities through ecological and evolutionary processes. Phylogenetic niche conservatism--the tendency of species to retain ancestral ecological distributions--is thought to influence which species from a regional species pool can persist in a particular environment. We analyzed data for seed plants in China to test hypotheses about the distribution of species within regional floras. Of 16 environmental variables, actual evapotranspiration, minimum temperature of the coldest month, and annual precipitation most strongly influenced regional species richness, phylogenetic dispersion, and phylogenetic diversity for both gymnosperms (cone-bearing plants) and angiosperms (flowering plants). For most evolutionary clades at, and above, the family level, the relationships between metrics of phylogenetic dispersion (i.e., average phylogenetic distance among species), or phylogenetic diversity, and the 3 environmental variables were consistent with the tropical niche conservatism hypothesis, which predicts closer phylogenetic relatedness and reduced phylogenetic diversity with increasing environmental stress. The slopes of the relationships between phylogenetic relatedness and the 3 environmental drivers identified in this analysis were steeper for primarily tropical clades, implying greater niche conservatism, than for primarily temperate clades. These observations suggest that the distributions of seed plants across large-scale environmental gradients in China are constrained by conserved adaptations to the physical environment, i.e., phylogenetic niche conservatism. [ABSTRACT FROM AUTHOR]

• The Physochlaina orientalis mitochondrial genome is the largest among the Solanaceae. • The P. orientalis mtDNA has many short repeats (SR) in tandem-like structures. • SR share a common origin in the Solanaceae, but only expanded in the Hyoscyameae. • We propose a mechanism to explain SR generation and expansion in the Hyoscyameae. • We study the short repeat content and their relationships in 136 seed plants. Short repeats (SR) play an important role in shaping seed plant mitochondrial genomes (mtDNAs). However, their origin, distribution, and relationships across the different plant lineages remain unresolved. We focus on the angiosperm family Solanaceae that shows great variation in repeat content and extend the study to a wide diversity of seed plants. We determined the complete nucleotide sequences of the organellar genomes of the medicinal plant Physochlaina orientalis (Solanaceae), member of the tribe Hyoscyameae. To understand the evolution of the P. orientalis mtDNA we made comparisons with those of five other Solanaceae. P. orientalis mtDNA presents the largest mitogenome (∼685 kb in size) among the Solanaceae and has an unprecedented 8-copy repeat family of ∼8.2 kb in length and a great number of SR arranged in tandem-like structures. We found that the SR in the Solanaceae share a common origin, but these only expanded in members of the tribe Hyoscyameae. We discuss a mechanism that could explain SR formation and expansion in P. orientalis and Hyoscyamus niger. Finally, the great increase in plant mitochondrial data allowed us to systematically extend our repeat analysis to a total of 136 seed plants to characterize and analyze for the first time families of SR among seed plant mtDNAs. [ABSTRACT FROM AUTHOR]

Despite substantial advances in genotyping techniques and massively accumulated data over the past half century, a uniform measurement of neutral genetic diversity derived by different molecular markers across a wide taxonomical range has not yet been formulated. We collected genetic diversity data on seed plants derived by AFLP, allozyme, ISSR, RAPD, SSR and nucleotide sequences, converted expected heterozygosity (He) to nucleotide diversity (π), and reassessed the relationship between plant genetic diversity and life history traits or extinction risk. We successfully established a uniform π criterion and developed a comprehensive plant genetic diversity database. The mean population-level and species-level π values across seed plants were 0.00374 (966 taxa, 155 families, 47 orders) and 0.00569 (728 taxa, 130 families, 46 orders), respectively. Significant differences were recovered for breeding system (p < 0.001) at the population level and geographic range (p = 0.023) at the species level. Selfing taxa had significantly lower π values than outcrossing and mixed-mating taxa, whereas narrowly distributed taxa had significantly lower π values than widely distributed taxa. Despite significant differences between the two extreme threat categories (critically endangered and least concern), the genetic diversity reduction on the way to extinction was difficult to detect in early stages.

Ｉｎ ｏｒｄｅｒ ｔｏ ｅｎｒｉｃｈ ｔｈｅ ｒｅｓｅａｒｃｈ ｄａｔａ ｏｆ ｔｈｅ Ｔｉｂｅｔａｎ Ｐｌａｔｅａｕ ｆｌｏｒａ, ａｎｄ ｔｏ ｆｕｒｔｈｅｒ ｓｔｕｄｙ ｏｎ ｖｅｇｅｔａｔｉｏｎ ｅｃｏｌｏｇｙ ａｎｄ ｄｅｖｅｌｏｐｍｅｎｔ, ｕｔｉｌｉｚａｔｉｏｎ ａｎｄ ｐｒｏｔｅｃｔｉｏｎ ｏｆ ｂｉｏｌｏｇｉｃａｌ ｒｅｓｏｕｒｃｅｓ ｉｎ Ｔｉｂｅｔ. Ｃｏｌｌｅｃｔｉｏｎ ｏｆ ｓｐｅｃｉｍｅｎｓ ａｎｄ ｒｅｆｅｒｅｎｃｅ ｏｆ ｒｅｌｅｖａｎｔ ｌｉｔｅｒａｔｕｒｅ, ｔｈｅ ｆｌｏｒａ ｏｆ ｓｅｅｄ ｐｌａｎｔｓ ｉｎ Ｐｅｉｋｕ Ｃｏ ｉｎ Ｔｉｂｅｔ ｗａｓ ａｎａｌｙｚｅｄ ｂａｓｅｄ ｏｎ ｆｉｅｌｄ ｓｕｒｖｅｙ. Ｔｈｅ ｒｅｓｕｌｔ ｗｅｒｅ ａｓ ｆｏｌｌｏｗｓ: (１) Ｆｌｏｒａ ｏｆ Ｐｅｉｋｕ Ｃｏ ｗａｓ ｎｏｔ ａｂｕｎｄａｎｔ. Ｔｈｅｒｅ ｗｅｒｅ ３１ ｆａｍｉｌｉｅｓ, ７７ ｇｅｎｅｒａ, １１５ ｓｐｅｃｉｅｓ, ａｃｃｏｕｎｔｉｎｇ ｆｏｒ １８.９０％, ６.７３％ ａｎｄ ２.１７％ ｏｆ ａｌｌ ｔｈｅ ｓｅｅｄ ｐｌａｎｔｓ ｉｎ Ｔｉｂｅｔ, ｉｎ ｗｈｉｃｈ ｔｈｅｒｅ ｗｅｒｅ ｔｗｏ ｇｙｍｎｏｓｐｅｒｍ ｓｐｅｃｉｅｓ, ｂｅｉｎｇ ｏｗｎｅｄ ｂｙ ｔｗｏ ｇｅｎｅｒａ ａｎｄ ｔｗｏ ｆａｍｉｌｉｅｓꎻ １１３ ａｎｇｉｏｓｐｅｒｍ ｓｐｅｃｉｅｓ, ｂｅｌｏｎｇｉｎｇ ｔｏ ７５ ｇｅｎｅｒａ ａｎｄ ２９ ｆａｍｉｌｉｅｓ. Ｉｎ ｔｈｅ ａｎｇｉｏｓｐｅｒｍｓ, ｔｈｅ ｄｉｃｏｔｓ, ｗｉｔｈ ９１ ｓｐｅｃｉｅｓ ｉｎ ５８ ｇｅｎｅｒａ ｏｆ ２３ ｆａｍｉｌｉｅｓ, ｗｅｒｅ ｐｒｅｄｏｍｉｎａｎｔ ｉｎ ｔｈｅ ｆｕｔｕｒｉｓｔｉｃ ｃｏｍｐｏｓｉｔｉｏｎ, ａｎｄ ｔｈｅ ｍｏｎｏｃｏｔｓ ｈａｄ ２２ ｓｐｅｃｉｅｓ ｉｎ １７ ｇｅｎｅｒａ ｏｆ ６ ｆａｍｉｌｉｅｓ. (２) Ｏｂｖｉｏｕｓ ａｄｖａｎｔａｇｅｏｕｓ ｆａｍｉｌｉｅｓ, ａ ｄｉｓｔｉｎｃｔ ｓｐｅｃｉｅｓ ｂｒａｎｃｈ ｒｅｐｒｅｓｅｎｔｅｄ ｔｈｅ ｃｅｒｔａｉｎ ａｄｖａｎｔａｇｅ. Ｏｆ ａｌｌ ｔｈｅ ｆａｍｉｌｉｅｓ, ｆｉｖｅ ｆａｍｉｌｉｅｓ ｈａｄ ａｔ ｌｅａｓｔ ｓｅｖｅｎ ｓｐｅｃｉｅｓ ｏｆ ｓｅｅｄ ｐｌａｎｔｓ, ａｃｃｏｕｎｔｉｎｇ ｆｏｒ ３９.１３％ｏｆ ｔｈｅ ｔｏｔａｌ ｓｐｅｃｉｅｓ ｉｎ ｔｈｅ ｓｔｕｄｙ ａｒｅａ, ｗｈｉｃｈ ｗａｓ ｔｈｅ ｍａｊｏｒ ｃｏｍｐｏｎｅｎｔ ｏｆ ｔｈｉｓ ｆｌｏｒａ. Ａｔ ｔｈｅ ｓａｍｅ ｔｉｍｅ, ｅｖｌｅｖｅｎ ｆａｍｉｌｉｅｓ ｃｏｎｔａｉｎｅｄ ｏｎｌｙ ｏｎｅ ｓｐｅｃｉｅｓ ｏｆ ｕｎｑｕｅｓｔｉｏｎａｂｌｅ ｂｅｎｅｆｉｔ ｐｌａｎｔｓ. (３) Ｔｈｅ ｆｕｔｕｒｉｓｔｉｃ ｇｅｏｇｒａｐｈｉｃａｌ ｃｏｍｐｏｓｉｔｉｏｎ ｏｆ ｔｈｉｓ ａｒｅａ ｗａｓ ｃｏｍｐｌｅｘ ｗｈｉｃｈ ｈａｄ ｔｈｒｅｅ ｄｉｓｔｒｉｂｕｔｉｏｎａｌ ｔｙｐｅｓ ｉｎ ｔｈｅ ｆａｍｉｌｙ ｌｅｖｅｌ, ｔｅｎ ｄｉｓｔｒｉｂｕｔｉｏｎａｌ ｔｙｐｅｓ ａｔ ｔｈｅ ｇｅｎｅｒａ ｌｅｖｅｌ. Ａｍｏｎｇ ｔｈｅｍ, ｔｅｍｐｅｒａｔｅ ｃｏｍｐｏｓｉｔｉｏｎｓ ｗｅｒｅ ｄｏｍｉｎａｎｔ ａｂｓｏｌｕｔｅｌｙ, ｆａｍｉｌｉｅｓ ａｎｄ ｇｅｎｅｒａ ｄｉｓｔｒｉｂｕｔｅｄ ｉｎ ｔｅｍｐｅｒａｔｅ ａｃｃｏｕｎｔｅｄ ｆｏｒ ２９.０３％ ａｎｄ ７７.９２％ ｏｆ ｔｏｔａｌ ｆａｍｉｌｉｅｓ ａｎｄ ｇｅｎｅｒａ ｒｅｓｐｅｃｔｉｖｅｌｙ, ｉｎｄｉｃａｔｉｎｇ ｔｈａｔ ｔｈｉｓ ａｒｅａ ｈａｓ ｏｂｖｉｏｕｓ ｔｅｍｐｅｒａｔｅ ｎａｔｕｒｅ. (４) Ｔｈｅｒｅ ｗａｓ ｎｏ ｄｉｓｃｅｒｎｉｂｌｅ ｐｅｃｕｌｉａｒ ｐｈｅｎｏｍｅｎｏｎ ｉｎ ｔｈｅ ｇｅｎｕｓ ａｎｄ ｎｏ ｄｉｓｔｒｉｂｕｔｉｏｎ ｅｎｄｅｍｉｃ ｆａｍｉｌｉｅｓ ｔｏ Ｃｈｉｎａ, ｂｕｔ ｏｎｅ ｇｅｎｕｓ ｅｎｄｅｍｉｃ ｔｏ Ｃｈｉｎａ, ｗｈｉｃｈ ｉｎｄｉｃａｔｅｓ ｔｈａｔ ｔｈｅ ｅｎｄｅｍｉｃ ｆｌｏｒａ ｏｆ Ｐｅｉｋｕ Ｃｏ ｉｓ ｖｅｒｙ ｌｏｗ, ａｎｄ ａｌｓｏ ｉｎｄｉｃａｔｅｓ ｔｈｅ ａｄｏｌｅｓｃｅｎｃｅ ｏｆ ａｌｐｉｎｅ ｆｌｏｒａ ｃｏｍｂｉｎｅｄ ｔｈｅ ｗｉｔｈ ｃｏｌｄ ａｎｄ ｄｒｏｕｇｈ, ａｎｄ ｐｌａｔｅｕ ｓｐｅｃｉａｌｉｚａｔｉｏｎ. [ABSTRACT FROM AUTHOR]