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Premise: Polypodium pellucidum, a fern endemic to the Hawaiian Islands, encompasses five ecologically and morphologically variable subspecies, suggesting a complex history involving both rapid divergence and rampant hybridization. Methods: We employed a large target‐capture data set to investigate the evolution of genetic, morphological, and ecological variation in P. pellucidum. With a broad sampling across five Hawaiian Islands, we deciphered the evolutionary history of P. pellucidum, identified nonhybrid lineages and intraspecific hybrids, and inferred the relative influence of geography and ecology on their distributions. Results: Polypodium pellucidum is monophyletic, dispersing to the Hawaiian archipelago 11.53–7.77 Ma and diversifying into extant clades between 5.66 and 4.73 Ma. We identified four nonhybrid clades with unique morphologies, ecological niches, and distributions. Additionally, we elucidated several intraspecific hybrid combinations and evidence for undiscovered or extinct "ghost" lineages contributing to extant hybrid populations. Conclusions: We provide a foundation for revising the taxonomy of P. pellucidum to account for cryptic lineages and intraspecific hybrids. Geologic succession of the Hawaiian Islands through cycles of volcanism, vegetative succession, and erosion has determined the available habitats and distribution of ecologically specific, divergent clades within P. pellucidum. Intraspecific hybrids have likely arisen due to ecological and or geological transitions, often persisting after the local extinction of their progenitors. This research contributes to our understanding of the evolution of Hawai'i's diverse fern flora and illuminated cryptic taxa to allow better‐informed conservation efforts. [ABSTRACT FROM AUTHOR]

Premise: Increasingly complete phylogenies underpin studies in systematics, ecology, and evolution. Myrteae (Myrtaceae), with ~2700 species, is a key component of the exceptionally diverse Neotropical flora, but given its complicated taxonomy, automated assembling of molecular supermatrices from public databases often lead to unreliable topologies due to poor species identification. Methods: Here, we build a taxonomically verified molecular supermatrix of Neotropical Myrteae by assembling 3909 published and 1004 unpublished sequences from two nuclear and seven plastid molecular markers. We infer a time‐calibrated phylogenetic tree that covers 712 species of Myrteae (~28% of the total diversity in the clade) and evaluate geographic and taxonomic gaps in sampling. Results: The tree inferred from the fully concatenated matrix mostly reflects the topology of the plastid data set and there is a moderate to strong incongruence between trees inferred from nuclear and plastid partitions. Large, species‐rich genera are still the poorest sampled within the group. Eastern South America is the best‐represented area in proportion to its species diversity, while Western Amazon, Mesoamerica, and the Caribbean are the least represented. Conclusions: We provide a time‐calibrated tree that can be more reliably used to address finer‐scale eco‐evolutionary questions that involve this group in the Neotropics. Gaps to be filled by future studies include improving representation of taxa and areas that remain poorly sampled, investigating causes of conflict between nuclear and plastid partitions, and the role of hybridization and incomplete lineage sorting in relationships that are poorly supported. [ABSTRACT FROM AUTHOR]

This article discusses the important role that microbes play in plant ecology and evolution. Microbes, which include diverse soil and foliar microbial communities, have a significant impact on various aspects of plant biology. They can influence maternal effects, phenotypic plasticity, and natural selection in plants. Ignoring the presence and effects of microbes can lead to a misunderstanding of plant processes and outcomes. Therefore, it is crucial for plant ecologists and evolutionary biologists to consider the influence of microbial communities in their research to gain a more accurate understanding of plant biology in the natural world. [Extracted from the article]

Decades of empirical research have revealed how the geological history of our planet shaped plant evolution by establishing well‐known patterns (e.g., how mountain uplift resulted in high rates of diversification and replicate radiations in montane plant taxa). This follows a traditional approach where botanical data are interpreted in light of geological events. In this synthesis, I instead describe how by integrating natural history, phylogenetics, and population genetics, botanical research can be applied alongside geology and paleontology to inform our understanding of past geological and climatic processes. This conceptual shift aligns with the goals of the emerging field of geogenomics. In the neotropics, plant geogenomics is a powerful tool for the reciprocal exploration of two long standing questions in biology and geology: how the dynamic landscape of the region came to be and how it shaped the evolution of the richest flora. Current challenges that are specific to analytical approaches for plant geogenomics are discussed. I describe the scale at which various geological questions can be addressed from biological data and what makes some groups of plants excellent model systems for geogenomics research. Although plant geogenomics is discussed with reference to the neotropics, the recommendations given here for approaches to plant geogenomics can and should be expanded to exploring long‐standing questions on how the earth evolved with the use of plant DNA. [ABSTRACT FROM AUTHOR]

The article discusses the relevance of experimental evolution in botanical research. While many researchers in botany acknowledge the importance of evolution in shaping plant traits and interactions, they often assume that ongoing evolutionary change is not fast enough to impact their research. However, recent research shows that evolution can be rapid in some cases, especially when selection is strong and the generation time of the organisms is short. The article argues that researchers should consider the opportunity for addressing real-time evolution in their research and incorporate an evolutionary framework in their experimental design. It also discusses different ways to study real-time evolution in plants, such as comparative approaches, resurrection experiments, and experimental evolution. The article highlights the challenges and advantages of studying real-time evolution in plants and emphasizes the importance of addressing evolutionary questions in plant conservation. It suggests that developing new fast-cycling model plant species could further advance real-time evolution research in botany. [Extracted from the article]

The article discusses the importance of understanding ontogenetic changes in plant adaptation. It highlights the significance of developmental transitions and the timing of these transitions in relation to environmental stress. The article emphasizes the need for integration between geneticists, molecular biologists, developmental biologists, and ecologists to gain a comprehensive understanding of how plant development contributes to environmental adaptation. It also explores the impact of environmental factors on the timing of developmental transitions and how these transitions can alter ecological selection. The authors call for further research to improve our understanding of ontogenetic changes in plant ecophysiology and environmental response. [Extracted from the article]

Keywords: development; ectopic cambia; evolution; secondary growth; successive cambia; vascular cambium; vascular variants EN development ectopic cambia evolution secondary growth successive cambia vascular cambium vascular variants 1 5 5 10/30/23 20231001 NES 231001 One of the most remarkable innovations in the evolution of vascular plants is secondary growth: the developmental process by which plants grow thicker. Development, ectopic cambia, evolution, secondary growth, vascular cambium, successive cambia, vascular variants By adopting the concept of ectopic cambia, we more readily see the links with transgenic phenotypes in model species that also use the term "ectopic cambia" (e.g., Kucukoglu et al., [7]) as a starting place to understand the naturally occuring ectopic cambia across plants. Although these works suggest overexpression of HD-ZIP III genes can induce cortex-derived ectopic cambia, this alone is not sufficient to hypothesize the molecular origins of the vast majority of ectopic cambia, which instead arise from vascular tissues (pericycle or phloem parenchyma). [Extracted from the article]

Premise: Cacti are characteristic elements of the Neotropical flora and of major interest for biogeographic, evolutionary, and ecological studies. We tested global biogeographic boundaries for Neotropical Cactaceae using specimen‐based occurrences, coupled with data from visual observations, as a means to tackle the known collection biases in the family. Methods: Species richness and record density were assessed for preserved specimens and human observations, and a bioregional scheme tailored to Cactaceae was produced using the interactive web application Infomap Bioregions, based on data from 261,272 point records cleaned through automated and manual steps. Results: We found that areas in Mexico and southwestern USA, in eastern Brazil, and along the Andean region have the greatest density of records and the highest species richness. Human observations complement information from preserved specimens substantially, especially along the Andes. We propose 24 cactus bioregions, among which the most species‐rich are northern Mexico/southwestern USA, central Mexico, southern central Mexico, Central America, Mexican Pacific coast, central and southern Andes, northwestern Mexico/extreme southwestern USA, southwestern Bolivia, northeastern Brazil, and Mexico/Baja California. Conclusions: The bioregionalization proposed shows biogeographic boundaries specific to cacti and can thereby aid further evolutionary, biogeographic, and ecological studies by providing a validated framework for further analyses. This classification builds upon, and is distinctive from, other expert‐derived regionalization schemes for other taxa. Our results showcase how observation data, including citizen‐science records, can complement traditional specimen‐based data for biogeographic research, particularly for taxa with specific specimen collection and preservation challenges and those that are threatened or internationally protected. [ABSTRACT FROM AUTHOR]

Premise: Understanding establishment and spread of non‐native plants is important in the face of a homogenizing global flora. While many studies focus on successful, invasive species, fewer have studied failed plant introductions. Until the early 1900s, large quantities of ship ballast, often containing foreign plant propagules, were deposited in New Jersey (USA). The resulting ballast flora is documented in extensive herbarium records, providing us a unique opportunity to analyze successes and failures of novel plant species introductions. Methods: We used digitized specimens from 75 herbaria to study 264 non‐native species introduced into New Jersey through 19th century ballast deposition. We used spatial (density‐based clustering; HDBSCAN) and temporal analyses of species retention and geographic spread to quantify disappearance rate, survival, and dispersion through time and define trajectory groups. Results: Four distinct trajectory groups were identified: waif (only present during import; 32% of species), short‐term (disappeared quickly; 20%), established–limited spread (survives locally, 30%), and established–widespread (widespread, 18%). Species disappearance rate was highest during ballast deposition and decreased soon after deposition stopped around 1900. Spatial patterns showed a strong association with 19th century railroads for inland dispersal from ports. The disappearance rate and spatial analyses are robust to herbarium collection bias. Conclusions: This study using New Jersey as a model is one of the few documenting multispecies successes and failures in inadvertent plant introductions. Results reveal distinct trends in species establishment and geographic spread and highlight the utility of herbarium specimens in answering questions that span large time scales. [ABSTRACT FROM AUTHOR]

Keywords: ecological interaction networks; ecological restoration; mutualism; mycorrhizal fungi; plant-microbial interactions; rhizobia; soil microbiome EN ecological interaction networks ecological restoration mutualism mycorrhizal fungi plant-microbial interactions rhizobia soil microbiome 1 5 5 10/03/23 20230901 NES 230901 More than three quarters of terrestrial habitats have been transformed by human activities (Ellis et al., [4]). Ecological interaction networks, ecological restoration, mutualism, mycorrhizal fungi, rhizobia, soil microbiome, plant-microbial interactions Rewiring critical plant-soil microbial interactions to assist ecological restoration We isolated DNA from the nodules of hickory wattle seedlings grown in the three soil types and used DNA barcoding to identify I Bradyrhizobium i strains that are characteristic of each soil type (i.e., indicator taxa; see Le Roux et al., [11] for similar methodologies). [Extracted from the article]

Keywords: arid ecosystems; deserts; drylands; functional traits; limiting resources; local adaptation; plant traits EN arid ecosystems deserts drylands functional traits limiting resources local adaptation plant traits 1 4 4 08/31/23 20230801 NES 230801 Population success is an elusive term that integrates assumptions regarding traits that enable individuals to respond to local conditions with assumptions regarding the effects of these traits on characteristics of the population in which the individuals grow. Arid ecosystems, deserts, drylands, functional traits, limiting resources, local adaptation, plant traits Dryland mechanisms could widely control ecosystem functioning in a drier and warmer world. In such a case, while part of the trait variation may result from non-adaptive responses, it is highly unlikely that the major driver of plant responses, as reflected by their trait composition and variability, is an inadequate ability of individuals to respond to local habitat conditions. [Extracted from the article]

Shifting focus from among to within species studies of intraspecific demographic variation and functional traits is needed because climate change effects on demography may vary among populations of the same species. However, species-level trait values are often applied to all individuals, regardless of their population or its abiotic and biotic environments, thus ignoring the range of trait variation within and among populations (Figure 1A). Keywords: demographic rates; environmental contexts; functional traits; interactive effects; intraspecific variation EN demographic rates environmental contexts functional traits interactive effects intraspecific variation 1 4 4 05/31/23 20230501 NES 230501 BACKGROUND Plant ecologists have long sought to quantify the drivers of variation in growth, survival, and reproductive output (Harper and White, [8]). Better integration of feedbacks between ecology and evolution will also lend insight into how traits, environment, and demography interact to drive population dynamics. [Extracted from the article]

Despite morphological similarity of lemmas and paleas in rice, lemma gene expression is similar to that of glumes, while palea gene expression is similar to that of lodicules and reproductive organs (Zong et al., [17]). Keywords: developmental genetics; evolution of floral development; floral homology; monocots; Poaceae; sepals; tepals EN developmental genetics evolution of floral development floral homology monocots Poaceae sepals tepals 1 4 4 05/03/23 20230401 NES 230401 Plant form is astonishingly diverse. If, for instance, ChINs for bract and sepal identity were defined, they could be compared to genes involved in lemma development to determine whether lemmas rely on the leaf ChIN, sepal ChIN, or a combination of both. [Extracted from the article]

The historian of the botanical sciences Andrew Denny Rodgers ([22]) insightfully noted that the years 1873-1892 were indeed "decades of transition", that saw the growth of the botanical sciences in these varied institutional contexts in the United States and that placed demands on botanists as professionals in contrast to self-taught "amateurs", now formally trained in areas of research and teaching. Public perceptions of science and scientists are generally positive in the United States (Pew Research Center, [19]; Funk et al., [8]), and one theme that resonates particularly strongly is the importance of conveying scientific findings; 80% of those surveyed ranked this point highly (American Academy of Arts and Sciences, [1]). New (or renewed) interest in science, especially in the context of botanical science, can inspire involvement in community science projects or motivate people to embrace a field in which they previously had no exposure or interest, often with new commitment for conservation and the public good. [Extracted from the article]

Although tree populations generally have high genetic diversity (Alfaro et al., [1]; Ingvarsson and Dahlberg, [10]), the widespread planting of cultivars may be reducing the genetic diversity of the urban forest. First, it is necessary to characterize the nature of the problem and better understand how diverse urban tree populations are, and if interbreeding between planted cultivars and naturally regenerating trees is in fact diluting the genetic diversity of urban tree populations. Cultivar, horticulture, genetic diversity, street trees, plant breeding Keywords: cultivar; genetic diversity; horticulture; plant breeding; street trees EN cultivar genetic diversity horticulture plant breeding street trees 1 3 3 07/19/23 20230701 NES 230701 Cities nationwide are pursuing ambitious tree canopy cover goals and tree planting initiatives because of the numerous perceived and quantified benefits of urban trees including urban heat island mitigation, stormwater runoff reduction, and beautification (Morgenroth et al., [14]; Doroski et al., [8]). [Extracted from the article]

High ploidy levels and large genomes rife with repetitive elements have historically challenged GEA for many nonmodel invasive grasses, necessitating reduced-representation approaches that capture only a fraction of full genomic variability. Invasive lineages may be more likely to have smaller genomes due to energetic costs of replication (Pysek et al., [15]), though larger genomes may be associated with increased flexibility (Stapley et al., [17]). Many invasive grasses drastically transform the ecosystems they invade, putting native communities across the globe at risk (Fusco et al., [5]). [Extracted from the article]

Most of the mentioned species-rich, hummingbird-pollinated plant clades have the highest species numbers, including many endemics, in the topographically highly structured (sub-)tropical mountain ranges that provide a number of different habitat types close to each other (e.g., Lagomarsino et al., 2016). If the ability for long-distance dispersal is missing, such as in many North American lineages of hummingbird-pollinated plants, for example, in hummingbird-pollinated clades of I Penstemon i , I Silene i (Caryophyllaceae), or I Monarda i (Lamiaceae), then these clades are rarely species-rich. Hummingbird pollination evolved numerous times independently and has been reported from 404 plant genera distributed over 68 angiosperm families (Abrahamczyk and Kessler, 2015). Why are some hummingbird-pollinated plant clades so species-rich?. [Extracted from the article]

The transition from self-incompatibility (SI) to self-compatibility (SC) has been argued to be one of the most common and influential evolutionary changes in flowering plants (Igic et al., [7]). For instance, in I Leptosiphon jepsonii i , self-pollen tube growth is inhibited in first day flowers, but as the flowers age the self-pollen tubes will research the ovule, resulting in delayed selfing (Goodwillie et al., [4]). The above examples of developmental decay of SI taxa with gametophytic self-incompatibility (GSI) demonstrate that the potential for progressive loss of self-pollen rejection with age transcends the underlying genetic system. (A) With phenotypic plasticity, the individual can recognize and reject self-pollen in normal environmental conditions; however, in stressed conditions, they are no longer able to reject self-pollen, and the self-pollen tubes germinate and fertilize the ovule. [Extracted from the article]

Premise: Two distinct types of fossil infructescences from the early Eocene Laguna del Hunco flora, Chubut Province, Patagonia, Argentina, preserve features of the family Cunoniaceae. The goal of the study was to assess their affinities within Cunoniaceae and to interpret their evolutionary and biogeographical significance. Methods: Specimens were collected from the Tufolitas Laguna del Hunco, Huitrera Formation. They were prepared, photographed, and compared morphologically with similar extant and fossil fruits and infructescences using published literature and herbarium material. Results: The fruit and infructescence morphology place the fossil taxa within Cunoniaceae. They do not conform to any extant genus, supporting the erection of two new fossil genera. Racemofructus gen. nov. shares diagnostic features of the tribe Cunonieae, especially Weinmannia s.l., and exhibits two tribal morphological synapomorphies: a racemose inflorescence and a replum composed of a single column. Cunoniocarpa gen. nov. specimens are paniculate inflorescences with basipetally dehiscent, bicarpellate capsules that have persistent styles and calyces. Its replum morphology suggests an affinity to the tribe Caldcluvieae, particularly to the genus Ackama. Conclusions: The new Patagonian fossils described herein constitute the oldest record of cunoniaceous capsules globally, supplementing a significant body of fossil evidence from pollen, wood, and reproductive structures from southern South America and Antarctica that suggests that the Cunoniaceae were diversified and widely distributed in the southern hemisphere by the early Eocene. Racemofructus and Cunoniocarpa are, respectively, the first fossil records from South America of reproductive structures with affinity to tribes Cunonieae and Caldcluvieae. [ABSTRACT FROM AUTHOR]

A comparison of diploid, neo-tetraploid, and evolved tetraploid plants (67 species) shows that, in many cases, cellular traits that are consistently affected by genome duplication (i.e., differ between diploids and neo-tetraploids), are ultimately not dramatically different when comparing diploids and evolved autopolyploids, suggesting that over evolutionary time they return to a diploid-like state (Bomblies, 2020). Thus, the signatures of selection on meiotic genes in tetraploids likely reflect a response to novel challenges caused by genome duplication, rather than diploid and tetraploid I A. arenosa i having distinct optima. Keywords: adaptive evolution; evolution; evolutionary cell biology; genome scan; meiosis; polyploid; protein evolution; trait maintenance EN adaptive evolution evolution evolutionary cell biology genome scan meiosis polyploid protein evolution trait maintenance 189 192 4 03/03/22 20220201 NES 220201 Like many evolutionary geneticists, I am fascinated by genes underlying potentially adaptive traits that differentiate populations. Many cellular traits are altered immediately by genome duplication, particularly cell size, which affects a wide range of physiological traits (Doyle and Coate, 2019). [Extracted from the article]

Premise: Continental‐scale disjunctions and associated drivers are core research interests in biogeographic studies. Here, we selected a species‐rich Australian plant genus (Calytrix; Myrtaceae) as a case study to investigate these patterns. Species of this endemic Australian starflower genus have a disjunct distribution across the mesic fringes of the continent and are largely absent from the arid center. Methods: We used high‐throughput sequencing to generate unprecedented resolution and near complete species‐level nuclear and plastid phylogenies for Calytrix. BioGeoBEARS and biogeographic stochastic mapping were used to infer ancestral areas, the relative contributions of vicariance and dispersal events, and directionality of dispersal. Results: Present‐day disjunctions in Calytrix are explained by a combination of scenarios: (1) retreat of multiple lineages from the continental center to the more mesic fringes as Australia became progressively more arid, with subsequent extinction in the center as well as (2) origination of ancestral lineages in southwestern Australia (SWA) for species‐rich clades. The SWA biodiversity hotspot is a major diversification center and the most common source area of dispersals, with multiple lineages originating in SWA and subsequently spreading to the adjacent arid Eremaean region. Conclusions: Our results suggest that major extinction, as a result of cooling and drying of the Australian continent in the Eocene–Miocene, shaped the present‐day biogeography of Calytrix. We hypothesize that this peripheral vicariance pattern, which is similar to the African Rand flora, may explain the disjunctions of many other Australian plant groups. Further studies with densely sampled phylogenies are required to test this hypothesis. [ABSTRACT FROM AUTHOR]

Keywords: biochemistry; cell biology; development; evolution; metabolomics; microbiome; nectar; nectar spur; nectary; nectaries; transcriptomics EN biochemistry cell biology development evolution metabolomics microbiome nectar nectar spur nectary nectaries transcriptomics 2326 2330 5 01/05/22 20211201 NES 211201 The relationship between flowering plant nectars and interacting animals is fundamental to plant fitness, shaping macroevolutionary and macroecological patterns of trait and community diversity. ACKNOWLEDGMENTS We thank all the people who presented at the Botany 2020 colloquium "Characteristics of nectar, nectaries and nectar spurs" (http://2020.botanyconference.org/engine/search/index.php?func=detail%26aid=937) and who contributed ideas and reviewed drafts of this essay: Evangeline Ballerini, Clay Carter, Molly Edwards, Amanda Katzer, Shawn Krosnik, Lachezar Nikolov, and Annika Smith. Given the association of nectaries with diverse plant structures, yet exhibiting an underlying nectar secreting function, a key question is whether similar genetic programs underlie nectary development. NECTARY CELL BIOLOGY AND PHYSIOLOGY Complex physiological and cellular processes with well-orchestrated molecular and biochemical events lead to nectar production, nectar secretion, and possibly nectar reabsorption (reviewed by Roy et al., 2017). [Extracted from the article]

Plant-focused studies with a G × E framework generally test microbiome effects on plant performance or stress tolerance not only for one narrow type of experimental set-up but across a range of different environments and/or multiple plant genotypes (Figure 1B). Keywords: evolutionary ecology; G × E; genotype-by-environment interactions; microbial communities; multifactorial experiments; natural variation; pathogens; stress tolerance EN evolutionary ecology G × E genotype-by-environment interactions microbial communities multifactorial experiments natural variation pathogens stress tolerance 1820 1823 4 11/02/21 20211001 NES 211001 Plant microbiomes have become one of the hottest topics in plant biology. Understanding plant microbiomes requires a genotype × environment framework Microbiome-focused studies with a G × E character essentially treat the microbiome as an "extended phenotype" of the plant that is subject to the same complex influences as other plant phenotypes. [Extracted from the article]

Premise: The conifer Geinitzia reichenbachii was a common member of the Cretaceous Laurasian floras. However, the histology of G. reichenbachii leafy axes was never described in detail, and our knowledge of its paleoecology remains very limited. Using new and exquisitely preserved silicified material from the Upper Cretaceous of western France, we describe G. reichenbachii from the gross morphology to the cellular scale, then discuss paleoecological and taphonomical implications. Methods: We examined specimens from two localities in western France (Claix and Moragne) using propagation phase‐contrast X‐ray synchrotron microtomography. Results: The cuticle and the inner tissues of leafy axes are preserved in three dimensions. Epidermis, hypodermis, palisade parenchyma, spongy parenchyma, transfusion tracheids, and most of tissues of the vascular cylinder are clearly discernible. The numerous resin ducts are sometimes filled by persisting resin. Additionally, surfaces of some leaves preserved drops and flows of resin. Conclusions: Depositional environmental context combined with histological features of G. reichenbachii suggest that this conifer was adapted to a range of marginal‐littoral ecosystems including those open to the sea paleoenvironments and innermost ones influenced by strong continental inputs. Geinitzia reichenbachii was adapted to withstand intense sunlight, hot temperatures coupled with salty sea wind, and dry conditions. The frequent amber‐bearing beds in the Cretaceous from western France with Geinitzia as a main component of the associated floras raises the possibility of a role for Geinitzia in the production of the "Charentese amber". [ABSTRACT FROM AUTHOR]

Premise: Genera that are widespread, with geographically discontinuous distributions and represented by few species, are intriguing. Is their achieved disjunct distribution recent or ancient in origin? Why are they species‐poor? The Rand Flora is a continental‐scale pattern in which closely related species appear codistributed in isolated regions over the continental margins of Africa. Genus Camptoloma (Scrophulariaceae) is the most notable example, comprising three species isolated from each other on the northwest, eastern, and southwest Africa. Methods: We employed Sanger sequencing of nuclear and plastid markers, together with genomic target sequencing of 2190 low‐copy nuclear genes, to infer interspecies relationships and the position of Camptoloma within Scrophulariaceae by using supermatrix and multispecies‐coalescent approaches. Lineage divergence times and ancestral ranges were inferred with Bayesian Markov chain Monte Carlo (MCMC) approaches. The population history was estimated with phylogeographic coalescent methods. Results: Camptoloma rotundifolium, restricted to Southern Africa, was shown to be a sister species to the disjunct clade formed by C. canariense, endemic to the Canary Islands, and C. lyperiiflorum, distributed in the Horn of Africa–Southern Arabia. Camptoloma was inferred to be sister to the mostly South African tribes Teedieae and Buddlejeae. Stem divergence was dated in the Late Miocene, while the origin of the extant disjunction was inferred as Early Pliocene. Conclusions: The current disjunct distribution of Camptoloma across Africa was likely the result of fragmentation and extinction and/or population bottlenecking events associated with historical aridification cycles during the Neogene; the pattern of species divergence, from south to north, is consistent with the "climatic refugia" Rand Flora hypothesis. [ABSTRACT FROM AUTHOR]

Premise: The Fagaceae comprise around 1000 tree species in the Northern Hemisphere. Despite an extensive fossil pollen record, reconstructing biogeographic patterns is hampered because it is difficult to achieve good taxonomic resolution with light microscopy alone. We investigate dispersed pollen of Fagaceae from the Miocene Søby flora, Denmark. We explore the latitudinal gradient in Fagaceae distribution during the Miocene Climatic Optimum (MCO) in Europe and the Northern Hemisphere to compare it with the Eocene Warmhouse and the present. Methods: We investigated dispersed pollen using light and scanning electron microscopy. We assessed biogeographic patterns in Fagaceae during two warm periods in Earth history (MCO, Eocene) and the present. Results: Eight species of Fagaceae were recognized in the Søby flora. Of these, Fagus had a continuous Mediterranean to subarctic distribution during MCO; Quercus sect. Cerris and castaneoids had northern limits in Denmark, and evergreen Quercus sect. Ilex in Central Europe. In a northern hemispheric context, Fagus and sections of Quercus had more northerly distribution limits during Eocene and MCO with maximum northward extensions during Eocene (Fagus, castaneoids) or Oligo‐Miocene (Quercus sects. Cerris and Ilex). The known distribution of the extinct Tricolporopollenites theacoides during MCO included Central Europe and East China, while this taxon thrived in South China during Eocene. Conclusions: More northerly distributions during MCO and Eocene probably were determined by temperature. In contrast, fossil occurrences in areas that are arid or semi‐humid today were determined by maritime conditions in these areas (western North America, Central Asia) during the Cenozoic. [ABSTRACT FROM AUTHOR]

Premise: Bryophytes (mosses, liverworts, and hornworts) tend to have very large geographic ranges, which impedes progress toward understanding the drivers of diversification and extinction. This study aimed to investigate whether North American endemics differ geographically from more widespread species and whether differences in climatic niche or traits related to dispersal and establishment differ between endemics and more widespread species. Methods: All available herbarium records of bryophytes from North America north of Mexico (106 collections) were used. Traits related to dispersal were obtained from the literature. Analyses tested whether range sizes and extents differed between endemics and nonendemics, and whether trait differences were associated with endemism. Climate data were used to determine whether differences in niche breadth are present between endemics and nonendemics, and whether suitable climate for endemics occurs outside North America. Results: Nonendemics have range sizes twice as large as endemics and they occur farther north and have greater longitudinal extents. However, they do not have the widest niche breadths and do not differ in spore size (with few exceptions) or sexual condition. Asexual propagules are more prevalent among nonendemics. Climatic models indicate that substantial areas of climate suitable for endemics exist outside of North America. Conclusions: Distributions of endemics and nonendemics are consistent with an important role of glaciation in shaping the North American bryophyte flora. Endemics are not limited to the continent based on a lack of suitable climate elsewhere or by spore size or sexual condition. [ABSTRACT FROM AUTHOR]

Although the Angiosperms353 probe set was designed specifically to target putative single-copy genes, the prevalence of WGD and polyploidy in flowering plants means that duplications and losses, even of these genes, are inevitable in many flowering plant lineages. Though often incomplete, the plastid genome data recovered as by-catch from target sequence capture libraries usually includes at least partial recovery of the ~78 protein-coding genes of the plastid genome, including genes such as I rbcL i or I matK i that have been widely used for decades in plant molecular phylogenetics. The unveiling of the angiosperm (flowering plant) tree of life over the past three decades has been one of the great success stories of modern plant biology. [Extracted from the article]

Here, we briefly review the historic and contemporary contributions that botanists have made in invasion biology and argue that botanists will continue to play a critical role in revolutionizing invasion biology. Keywords: colonization; establishment; genomics; herbaria; introduced species; weed science EN colonization establishment genomics herbaria introduced species weed science 549 552 4 04/28/21 20210401 NES 210401 Although botanists have been at the center of invasion biology since its inception, few botanists identify as invasion biologists. MOVING INVASION BIOLOGY FORWARD The examples above demonstrate the significant contributions that botanists are making to invasion biology, but botanists are also well poised to overcome some of the mechanistic hurdles that have long encumbered invasion biology as a field. [Extracted from the article]

GENE EXPRESSION ANALYSIS IN GINKGO OVULES REVEALS BOTH DIFFERENCES AND SIMILARITIES WITH ANGI... GRAPH Ovule development is a key process for seed-plant reproduction. D'Apice et al. describe the expression domains of key orthologous genes in I Ginkgo biloba i ovule development, examining early gene expression patterns during ovule initiation and at a late developmental stage in just-pollinated ovules. Together with publicly available genomes and transcriptomes, the authors show that the monkeyflower genus, I Mimulus i L., in its broad sense, is polyphyletic, and they pinpoint areas with elevated levels of gene tree discordance and potential introgression. [Extracted from the article]

RESOLVING SPECIES BOUNDARIES: MULTIPLE SPECIES DELIMITATION APPROACHES APPLIED TO NORTH AMERI... GRAPH Species limits are indistinct in many taxonomic groups, despite obvious morphological, ecological, and molecular differences. Two single-locus methods provided unrealistic projections of species estimates, whereas the multi-locus method Tr2 estimated 13 species, which corresponds well with other sources of evidence. GRAPH Annual, obligate outcrossing plants depend on pollinators to reproduce; however, when pollinators are absent, selection can result in the reduction of floral traits important in pollinator attraction. [Extracted from the article]

Consistent with a role in sporophyte maturation and desiccation, a function that is antithetic to that of tracheophyte stomata, hornwort and moss stomata including those of I Funaria i (Fig. In tracheophytes, stomata are found on the surface of leaves; in mosses, stomata, when present, are confined to the solitary spore capsule in the unbranched sporophyte (Paton and Pearce, 1957). This argument is somewhat problematic considering that the bryophyte ancestor likely emerged before the appearance of vascular plants (Wellman et al., 2003) (although there are no fossils of bryophytes in the Rhynie Chert, one of the oldest known macrofossil land plant assemblages), yet did not evolve to fill the ecological niche rapidly occupied by early vascular plants. Keywords: bryophytes; evolution; Polytrichum; PAP; 3'-phosphoadenosine 5'-phosphate; plant height; Sphagnum; stomata EN bryophytes evolution Polytrichum PAP 3'-phosphoadenosine 5'-phosphate plant height Sphagnum stomata 366 371 6 04/02/21 20210301 NES 210301 The greatest cost associated with terrestrial photosynthesis is maintaining hydration in the presence of phenomenal evaporative forces from the atmosphere (Wong et al., 1979). [Extracted from the article]

Tree architecture and functioning facing multispecies environments: We have gone only halfway in fruit-trees Keywords: agroecology; agroecosystem; agroforestry; biodiversity; biotic and abiotic environment; forest; forest tree; orchard EN agroecology agroecosystem agroforestry biodiversity biotic and abiotic environment forest forest tree orchard 3 7 5 02/04/21 20210101 NES 210101 Plant architecture analysis aims at deciphering the relative roles of endogenous processes and exogenous above- and belowground factors in the morphological development and functioning of a plant. GLO:ABO/01jan21:ajb21598-fig-0001.jpg PHOTO (COLOR): 1 Traditional multilayered cocoa-agroforestry system in Cameroon including from top to bottom, trees grown as shade trees for wood and medicinal products (top layer with large reiterative branches), for fruit (avocado or cola nuts; top-medium layer) that are overtopping oil palm trees, and citrus and cocoa trees (medium layer). At the system scale, the conventional way to design an orchard is to fit various pieces together considering the fruit tree itself (cultivar and rootstock if any), planting density, tree arrangement, support system, and tree and branch management over consecutive years. [Extracted from the article]

Botany, cyanobacteria, endosymbiosis, horizontal inheritance, lateral gene transfer, oxygenic photosynthesis, phototrophy, phycology, plastid evolution Origin and evolution of plastids and photosynthesis in eukaryotes. Keywords: botany; cyanobacteria; endosymbiosis; horizontal inheritance; lateral gene transfer; oxygenic photosynthesis; phototrophy; phycology; plastid evolution EN botany cyanobacteria endosymbiosis horizontal inheritance lateral gene transfer oxygenic photosynthesis phototrophy phycology plastid evolution 363 365 3 03/31/22 20220301 NES 220301 Biology is replete with terminology that is sometimes excessive. Several dinoflagellate genera have more recently reacquired and integrated plastids of haptophyte (Karenia, Karlodinium), green algal (Lepidodinium) or diatom origin (Durinskia, Kryptoperidinium) by means of endosymbiosis or predation/kleptoplasty. [Extracted from the article]

Keywords: crop evolution; genetic constraints; incomplete domestication; orphan crops EN crop evolution genetic constraints incomplete domestication orphan crops 1617 1621 5 12/30/20 20201201 NES 201201 INTRODUCTION The domestication of plants and animals was one of the most significant changes in human history. Crops that combine most domestication traits and consequently are well adapted to agroecological environments can be considered fully domesticated, while those that only display a few crop traits may be considered as incompletely domesticated. A lack of selection during early domestication is insufficient to explain incomplete trait adaptation because archaeological and genetic evidence suggest that minor crops have received equal selection pressure as fully domesticated crops. However, continuous strong gene flow from the ancestral species and other wild relatives into the crop might have prevented the isolation of the crop population and hampered the evolution of domestication traits. [Extracted from the article]

Premise: We tested 25 classic and novel hypotheses regarding trait–origin, trait–trait, and trait–environment relationships to account for flora‐wide variation in life history, habit, and especially reproductive traits using a plastid DNA phylogeny of most native (96.6%, or 1494/1547 species) and introduced (87.5%, or 690/789 species) angiosperms in Wisconsin, USA. Methods: We assembled data on life history, habit, flowering, dispersal, mating system, and occurrence across open/closed/mixed habitats across species in the state phylogeny. We used phylogenetically structured analyses to assess the strength and statistical significance of associations predicted by our models. Results: Introduced species are more likely to be annual herbs, occupy open habitats, have large, visually conspicuous, hermaphroditic flowers, and bear passively dispersed seeds. Among native species, hermaphroditism is associated with larger, more conspicuous flowers; monoecy is associated with small, inconspicuous flowers and passive seed dispersal; and dioecy is associated with small, inconspicuous flowers and fleshy fruits. Larger flowers with more conspicuous colors are more common in open habitats, and in understory species flowering under open (spring) canopies; fleshy fruits are more common in closed habitats. Wind pollination may help favor dioecy in open habitats. Conclusions: These findings support predictions regarding how breeding systems depend on flower size, flower color, and fruit type, and how those traits depend on habitat. This study is the first to combine flora‐wide phylogenies with complete trait databases and phylogenetically structured analyses to provide powerful tests of evolutionary hypotheses about reproductive traits and their variation with geographic source, each other, and environmental conditions. [ABSTRACT FROM AUTHOR]

Plasticity in selective embryo abortion may limit the mating costs of geitonogamy in self-compatible plants: a hypothesis Keywords: geitonogamy; plant mating; pollen limitation; reproductive assurance; seed and pollen discounting; selective embryo abortion; self-fertilization EN geitonogamy plant mating pollen limitation reproductive assurance seed and pollen discounting selective embryo abortion self-fertilization 390 393 4 03/24/20 20200301 NES 200301 Geitonogamy involves pollination of flowers by pollen from other flowers on the same plant. We propose that after ovules are selfed through geitonogamy, they can mature into seeds, providing reproductive assurance if cross-fertilized ovules are limiting, but that selfed ovules will be preferentially aborted if cross-fertilized ovules are abundant. However, if we consider the entire pollination and fertilization process, geitonogamy may still cause some seed discounting because ovules selfed through geitonogamy could be otherwise outcrossed. [Extracted from the article]

Keywords: Belowground organs; coarse roots; fine roots; plant drawing; rhizomes; tubers EN Belowground organs coarse roots fine roots plant drawing rhizomes tubers 385 389 5 03/24/20 20200301 NES 200301 THE MISSING PART Despite advances in visualization techniques, drawings are still an important tool for generalization and simplification of concepts in plant sciences. In this contribution, we provide key examples of common types of belowground plant organs showing fine roots as well as coarse organs, such as thick roots and rhizomes, either in a more realistic or more schematic fashion (see Figs. and). We call for a broader research agenda in plant functional ecology, especially for the belowground compartments (Klimesová et al., [11]), which would include overlooked plant traits and functional axes, such as those associated with plant modularity (Klimesová et al., [12]). Belowground organs, coarse roots, fine roots, plant drawing, rhizomes, tubers. [Extracted from the article]

Plant-environment interactions from the lens of plant stress, reproduction, and mutualisms In this issue of I AJB i , the plant-environment interaction is considered from the lens of environmental stressors, mutualisms, and plant reproduction. Plant reproduction is a critical plant life history trait responsible for plant population persistence, and in this section, interactions between plants and their pollinators and the effect of environmental stressors on plant reproduction are highlighted. Finally, Nihranz et al. ([16]) also examine the effects of plant damage on reproduction, using a transgenerational approach in I Solanum carolinense i by looking at the consequences of both maternal plant herbivory and inbreeding on offspring reproduction. [Extracted from the article]

Very little wild genetic diversity is preserved at INERA Yangambi, so enriching the coffee collection with local wild shrubs would increase the genetic resources for breeding and support I ex situ i conservation. They found that wild Robusta coffee shrubs in the region's forests are genetically different from cultivated shrubs in backyards and the INERA collection. GRAPH Subterraneous eel traps are exclusively found in carnivorous corkscrew plants, I Genlisea i (Lentibulariaceae), a genus that comprises 30 species from Africa (including Madagascar) and South America. [Extracted from the article]

Using an extensive meta-analysis of the pollinator-effectiveness literature, Page et al. compare the single-visit effectiveness of honeybees and other floral visitors. Karban and Pearse investigated these strategies when an unusual winter windstorm broke many branches in an arboretum containing 45 oak species in California. GRAPH Honeybees are globally dominant plant visitors, but are they effective pollinators?. [Extracted from the article]

METABARCODING REVEALS HIDDEN MICROBIAL DIVERSITY IN HORNWORTS GRAPH Hornworts (Anthocerophyta) are the only plant phylum in which all species form specialized nitrogen-fixing symbioses. GRAPH Plant species in a community can inadvertently exchange pollen when they rely on shared pollinators. ASSOCIATIONS WITH MYCORRHIZAL FUNGI ARE MORE COMMON AMONG HAWAIIAN NATIVE PLANT SPECIES THAN... GRAPH The mutualism between root-inhabiting fungi and plants, known as mycorrhizae, is common across most plant families and throughout the world. [Extracted from the article]

Molecular framework underlying floral bilateral symmetry and nectar spur development in Tropaeolum, an atypical member of the Brassicales. Molecular framework underlying floral bilateral symmetry and nectar spur development in Tropaeolum, an atypical member of the Brassicales. GRAPH Nasturtiums ( I Tropaeolum i spp., Tropaeolaceae) are the only members of the Brassicales that develop nectar spurs and bilaterally symmetrical flowers. [Extracted from the article]

Having a history of 25 years, with the first PBC taking place in Montpellier (France) in 1994 and the most recent one in Montreal (Canada) in 2018, the PBC sessions mirror, on the one hand, the most exciting research areas in plant biomechanics over the last quarter of a century and, on the other, may help to answer the question "Quo vadis plant biomechanics?" Appearing at (almost) all PBCs, the sessions Trees & Wood (9/164); Cells, Cell Walls & Tissues (9/160); Ecology & Evolution (9/112); Morphogenesis & Growth (8/97); and Applied Biomechanics & Biomimetics (8/93) can be considered as the core topics that are of ongoing scientific interest for the plant biomechanics community. The increasing flexibility in older liana stems is always achieved by the production of a less-dense, flexible secondary wood with huge-diameter vessels that additionally enable sufficient water conduction within the slender liana stems, which are often several hundreds of meters long (Fig.). In particular, we wish to inspire molecular biologists to join the bandwagon of biomechanics and to converge the newest molecular approaches and results with questions concerning (whole plant) organismic botany as addressed in biomechanics. [Extracted from the article]

Premise: The proportion of woody dicots with toothed leaves increases toward colder regions, a relationship used to reconstruct past mean annual temperatures. Recent hypotheses explaining this relationship are that (1) leaves in colder regions are thinner, requiring thick veins for support and water supply, with the resulting craspedodromous venation leading to marginal teeth (support–supply hypothesis) or that (2) teeth are associated with the packing of leaf primordia in winter buds (bud‐packing hypothesis). Methods: We addressed these hypotheses by examining leaf thickness, number of primordia in buds, growing season length (mean annual temperature, MAT), and other traits in 151 deciduous woody species using georeferenced occurrences and a Bayesian model controlling for phylogeny. We excluded evergreen species because longer leaf life spans correlate with higher leaf mass per area, precluding the detection of independent effects of leaf thickness on leaf‐margin type. Results: The best model predicted toothed leaves with 94% accuracy, with growing season length the strongest predictor. Neither leaf thickness nor number of leaves preformed in buds significantly influenced margin type, rejecting the support–supply and bud‐packing hypotheses. Conclusions: A direct selective benefit of leaf teeth via a carbon gain early in the spring as proposed by Royer and Wilf (2006) would match the strong correlation between toothed species occurrence and short growing season found here using Bayesian hierarchical models. Efforts should be directed to physiological work quantifying seasonal photosynthate production in toothed and nontoothed leaves. [ABSTRACT FROM AUTHOR]

Premise: Ex situ seed banking is critical for plant conservation globally, especially for threatened floras in tropical ecosystems like Hawai'i. Seed bank managers must maximize longevity, and species managers must plan restoration before seeds lose viability. Previous observations suggested some native Hawaiian seeds lost viability in frozen storage (−18°C). We investigated seed storage behavior in the Hawaiian flora to optimize storage conditions and recommend re‐collection intervals (RCI) to maximize viability of stored seeds. Methods: Using 20+ years of real‐time seed storage viability data, we tested freeze sensitivity for 197 species and calculated RCIs for 295 species. Using paired tests of accessions stored >2 yr at 5°C and −18°C, we developed an index of relative performance to determine freeze sensitivity. We calculated RCIs at 70% of highest germination (P70). Results: We identified four families (Campanulaceae, Cyperaceae, Rubiaceae, and Urticaceae) and four genera with seed freeze sensitivity and six additional genera with likely freeze sensitivity. Storage longevity was variable, but 195 species had viability >70% at the most recent tests (1 to 20+ yr), 123 species had RCIs >10 yr, and 45 species had RCIs <5 yr. Conclusions: Freeze sensitive storage behavior is more widely observed in Hawai'i than any other regional flora, perhaps due to insufficient testing elsewhere. We present a new protocol to test seed freeze sensitivity, which is often not evident until 2–5 years of storage. Re‐collection intervals will guide restoration practices in Hawai'i, and results inform seed conservation efforts globally, especially tropical and subtropical regions. [ABSTRACT FROM AUTHOR]