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In wood, lateral transport of water and minerals occurs readily in ‘integrated’ trees but is more restricted in ‘sectored species’. Dye distribution and a novel hydraulic technique are used to quantify species-specific differences in sectoriality in three temperate hardwoods, Betula papyrifera, Acer saccharum and Quercus rubra. Sectoriality was related to key elements of xylem structure: intervascular pitting, vessel diameter and vessel grouping. Perfusion of 0.5% safranin through isolated roots showed root-to-branch dye transport was most extensive in B. papyrifera and least extensive in Q. rubra. To test sectorialty using hydraulics, 20 mm KCl solution was pushed at 0.1 MPa through 5-cm wood segments, before and after occluding the direct axial outlet with glue, with flow rate measured in grams of solution expelled over time. Direct (axial) conductance (g MPa−1 s−1) through unglued outlets was compared with indirect (tangential) conductance around occluded outlets. Species with high indirect/direct conductance ratios (Integration Index) are the most integrated. Integration Index ranged from 0.26 in B. papyrifera to 0.02 in Q. rubra. Macerates showed that B. papyrifera has much greater percentage of cell wall area covered with intervascular pits than does A. saccharum or Q. rubra. Vessel grouping was closest in B. papyrifera and vessels were most isolated in Q. rubra. Widest diameter vessels occurred in Q. rubra, where they concentrated in springwood. Intervascular pitting, vessel diameter and grouping are wood traits that contribute to the continuum of sectoriality in trees, and may influence the ability of tree species to dominate in homogeneous or in patchy environments. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 150, 61–71. [ABSTRACT FROM AUTHOR]

This paper aims to shed light on distribution patterns and the relationship between species diversity and environmental heterogeneity of 17 Edraianthus taxa. We examined present and past distributions (Last Glacial Maximum) by applying ecological niche modelling. The environmental space occupied by the taxa was analysed using niche comparison methods. The results support the idea that the central and southern Dinaric Alps represent a centre of diversity and endemism in the western Balkan Peninsula. Diversity in Edraianthus is best explained by topographic (slope) and bioclimatic predictors (maximum temperature of warmest month, precipitation seasonality, precipitation of warmest quarter, precipitation of coldest quarter), suggesting that mountain areas with the most diversified relief have higher diversity. Niche modelling results suggest considerable range dynamics during the climatically unstable Quaternary. Thermophilic and lowland taxa responded with longitudinal shifts to ecologically suitable areas farther south, whereas high-mountain taxa responded mainly with elevational shifts. The greatest niche similarity is found among phylogenetically closely related taxa and among ecologically similar and often sympatric taxa. The least similarity was observed in species with marked differences in habitat elevation and in more geographically isolated species. Our results suggest that the extent of range and niche overlap varied among some taxa throughout their evolutionary history, which may have led to diversification at both allopatric and sympatric levels. The correlation between the genetic diversity of the most widespread taxon and the richness of taxa could be a consequence of past and present contacts. On the other hand, alternate periods of isolation may have favoured the emergence of taxa that are reproductively isolated and ecologically specialized. [ABSTRACT FROM AUTHOR]

Syzygium is a large genus (1200–1500 species) of Old World tropical trees, currently divided into five subgenera containing widely different numbers of species. Syzygium subgenus Perikion was defined by the presence of fibre bundles in the hypanthium wall, although until now this feature has not been investigated or images published. Furthermore, discovery of fibre bundles in certain species outside Syzygium subgenus Perikion calls for reassessment of the subgenus. In this paper, a morphological analysis is presented for all species previously associated with Syzygium subgenus Perikion or known to have fibre bundles. Results indicate the need for description of a new subgenus, Syzygium subgenus Oborapi , characterized by a distinctly goblet-shaped calyx, presence of fibre bundles in the hypanthium/mesocarp, prominent black lenticels on the abaxial leaf surface, ascending ovule orientation and species diversity centred on the Sunda Shelf. Fibre bundles are photographed and documented for the first time from a range of species and at different magnifications. A preliminary list of species is presented for Syzygium subgenus Perikion and Syzygium subgenus Oborapi , with recommendations for further investigation. [ABSTRACT FROM AUTHOR]

The paper deals with the seed morphology and anatomy of 32 wild Indian Musaceae by using light microscopy (LM) and scanning electron microscopy (SEM). This is the first comprehensive investigation into the seed micro-morphological and anatomical aspects of two genera of the family. Seed characters including shape, size, surface sculpturing (LM and SEM), seed coat thickness, layer characters and chalazal chamber column were considered. Seed characters play a significant role in the delimitation of taxa as they are more stable than vegetative (anatomical) and pollen features. Four types of seeds (oblate, ovoid, sub-globose and ellipsoid) were observed in the family, oblate seeds being the most common. LM revealed that most of the seeds have verrucate surface sculpturing, but some are smooth-verrucate or smooth. Seed size also plays an important role in the identification of the taxa to some extent. Number of layers and seed coat thickness are directly proportional to seed size. However, the thickness of endotesta, tegmen and inner endosperm layers (aleurone layers) differ in small and large seeds. The present study revealed eight types of outer sculpturing and three inner sculpturing patterns with diverse nature of anticlinal and periclinal cell walls. Based on the seed characters, a phenetic analysis was also carried out. [ABSTRACT FROM AUTHOR]

In a recent research article by Pace et al. (2019) , the authors claimed to have used information from phenology, morphology and molecular phylogenetics in their nomenclatural review of the Spiranthes sinensis complex. However, there are several scientific and botanical nomenclature issues with the Pace et al. (2019) paper in addition to its many errors and misinformation, which can be severely misleading and have the potential to affect our understanding of the highly complex Asian Spiranthes group. Here, we compare and critique their study in light of our study published prior to the article in the Botanical Journal of the Linnean Society. We suggest that the authors should have resorted to improved and new molecular data and a truly integrative analysis to support: (1) re-circumscription of the S. sinensis species complex for each of the six species they recognized, and the treatment of S. hongkongensis as a hybrid; and (2) all the new synonymies they proposed for Asian Spiranthes. [ABSTRACT FROM AUTHOR]

This paper aims to integrate cytogenetic and ecological approaches into a phylogenetic framework to better understand the evolution and systematics of Senna series Aphyllae , an endemic group of arid and semi-arid regions of South America. We counted the chromosome numbers at the population level in three species of series Aphyllae using a conventional technique (GIEMSA) and in situ hybridization (FISH). Phylogenetic reconstructions and inference of chromosome evolution were based on four plastid DNA regions and one nuclear marker. A principal component analysis was carried out using environmental data. Finally, ecological niche models (ENM) were implemented: (1) to identify the abiotic factors that constraint the potential geographical distribution of series Aphyllae and (2) to understand the ecological drivers for species diversification. The basic chromosome number is x = 12. Senna aphylla showed three cytotypes with (2 n = 24, 48 and 60) and S. pachyrrhiza has two cytotypes (2 n = 24 and 48). Senna crassiramea appeared to be polyploid with 2 n = 48. In diploid S. pachyrrhiza , two 45S and three 5S rDNA sites were reported. In tetraploid S. crassiramea , four 45S and four 5S rDNA sites were detected. The ENM and ecological speciation tests suggest that in series Aphyllae speciation was sometimes associated with conservatism and sometimes with niche divergence. Our results contribute to the evolutionary knowledge of Neotropical legumes and understanding of drivers of diversification in arid regions in South America. [ABSTRACT FROM AUTHOR]

Mapanoioideae are one of two subfamilies of Cyperaceae and consist of 186 species. Molecular phylogenetic relationships in subfamily Cyperoideae have recently been studied well, whereas evolutionary relationships in Mapanioideae remain little known. Subfamily Mapanioideae include two tribes. This study focuses on Hypolytreae, which is represented by three genera in Africa (Hypolytrum , Mapania and Principina). In this paper, we present the first molecular phylogenetic study of African Hypolytreae using a Sanger sequencing approach. We aim to (1) test whether Hypolytrum , Mapania and Principina are reciprocally monophyletic; (2) investigate whether the morphologically based sections in Hypolytrum and Mapania represent monophyletic taxa; (3) resolve species delimitation where multiple accessions could be sequenced and (4) explore the relationships of species occurring in West Tropical Africa vs. Central Africa. Our phylogenetic analyses strongly support Mapania and Hypolytrum as separate genera, but Principina is nested in Hypolytrum. This result is consistent with morphological differences. Mapania spp. are obligate rainforest species, but our results show that species from West Tropical Africa and species from Central Africa do not form separate clades. Dispersal between these regions may have happened during interglacial periods when the rainforest was continuous. [ABSTRACT FROM AUTHOR]

Floral morphological adaptations and composition of secretions aim to ensure reproductive success. Maxillariella is part of the largest subtribe of Orchidaceae, and Maxillariella spp. are important components of the orchid flora of the Neotropics. The aim of this paper was to provide a detailed study of the reproductive biology of three morphologically and geographically distinct species: M. sanguinea , M. variabilis and M. vulcanica. For many years, species in this group were considered rewardless, but several studies have revealed that lips of some species may secrete resins. However, most published research has mainly focused on investigating either micromorphology (SEM, TEM, histochemistry) or fragrance composition (GC–MS). In this study, we make the first attempt to investigate Maxillariella flowers in a more comparative manner by combining both aspects. In all investigated species we reported the presence of resins with lipids, sugars and/or proteins, suggesting a potential role as a food reward. Scant quantities of residues indicate that they are produced periodically in small quantities. Chemical analysis revealed significant differences between species, however, the presence of some compounds was constant. Cycloartenal and cycloartenol (main ingredients of resin and wax-like material in some Maxillariinae) were not been found. [ABSTRACT FROM AUTHOR]

Downloaded from https://academic.oup.com/botlinnean/article/195/3/249/6106223 by 81695661, OUP on 03 March 2021 PLANT ANATOMY: AT THE HEART OF MODERN BOTANY 251 © 2021 The Linnean Society of London, Botanical Journal of the Linnean Society, 2021, 195, 249-253 Selaginella moellendorffii Hieron. has a shoot apical meristem with only one initial cell, but this is unlikely to be an ancestral lycopod meristem type. 249 © 2021 The Linnean Society of London, Botanical Journal of the Linnean Society, 2021, 195, 249-253 Botanical Journal of the Linnean Society, 2021, 195, 249-253. More importantly, developmental biology of plants explores functioning of plant meristems and aspects of cell and tissue differentiation, the topics that have a long history of research in the framework of plant anatomy. © 2021 The Linnean Society of London, Botanical Journal of the Linnean Society, 2021, 195, 249-253 Professor A.C. Timonin, an English translation of her work on classification of plant meristems has been recently published (Lotova, 2020). [Extracted from the article]

Nodes are interfaces between stems and leaves. Vascular bundles originate here and elongate into leaves and internodes. In Marantaceae, internodal bundles are highly diverse, including inverted bundles in the climbing genus Haumania. The objective of this paper is to characterize bundle forms, their position across the stem and their connection to leaves and short shoots in Haumania spp. and other unrelated African branch-angle climbers in the family (Hypselodelphys , Trachyphrynium). We question whether bundle inversion is a genus-specific trait in Haumania or related to the climbing growth form. Vascular bundles in internodes are scattered across the stem diameter in a characteristic pattern. Four (to five) bundle types follow each other in a centripetal order from highly sclerenchymatic 'a'-bundles close to the epidermis to 'd'-bundles in the centre with a low sclerenchyma proportion. Inverted bundles only appear in internodes of Haumania , making this trait a synapomorphy for the genus. The nodes show stem, leaf and short shoot bundles in a remarkably diverse pattern with partitioned phloem clusters and apparently augmented xylem elements. Our preliminary conclusion is that the inversion of bundles happens when leaf and short shoot traces join the main axis bundle layers. [ABSTRACT FROM AUTHOR]

Understanding vascular bundle systems in angiosperms is a challenge. On the one hand, the vascular tissue is extremely important in reconstructing the evolution and survivability of plants, but on the other hand, it forms a complicated three-dimensional system of controversially discussed phylogenetic and ontogenetic origin. To increase clarity, in this paper we briefly summarize histological, phylogenetic and molecular aspects of primary vascular bundle formation in angiosperms, adding histological data on early stages of vascular bundle formation, proposing a concept combining the different views and providing simplified illustrations to improve the understanding of primary vascular systems in angiosperms. Based on the auxin hypothesis, vascular bundle formation is stimulated by the development of leaf primordia. Provascular domains appear at the base of the leaf primordia and develop into two directions (leaf, internode). The low vs. high number of internodal bundles, their circular vs. scattered arrangement and the open vs. closed bundle construction in eudicots vs. monocots can be deduced to be due to processes below the shoot apical meristem. The most important processes distinguishing monocots from eudicots are the isolated bundle initiation outside the primary meristem, the enormous expansion of the leaf bases associated with a high number of vascular bundles and the early onset of primary thickening passively dislocating vascular bundles. [ABSTRACT FROM AUTHOR]

Pteropyrum is a small genus of Polygonaceae with four species from the arid regions of Iran and adjacent countries. Pteropyrum spp. are not precisely delimitated and are difficult to identify because of their high plasticity in morphological characters. Pteropyrum (C3) has a close affinity to Calligonum (C4) and is therefore a suitable case for C4 evolutionary studies. We investigated the morphology and micromorphology (including pollen morphology) of Pteropyrum and elucidated the phylogenetic relationships with Atraphaxis and Calligonum using nuclear ITS sequences. Characteristics of the photosynthetic tissues such as volume and number of layers of primary carbon assimilation tissues (PCA) and photosynthetic carbon reduction tissue (PCR) were studied. In addition, the leaf and cotyledon anatomical characters of Pteropyrum (C3), Atraphaxis (C3) and Calligonum (C4), and their δ 13C values were compared to look for evolutionary changes in assimilating organs. The molecular phylogenetic tree identifies two strongly supported clades in Pteropyrum and its close relationship with Calligonum , confirming previous studies. Some morphologically similar species belong to different clades, which is probably due to convergent evolution and homoplasy. Leaf anatomical studies show that Atraphaxis has a multilayered mesophyll tissue, whereas Calligonum has one-layered mesophyll cells. The volume and layer number of mesophyll tissue cells decreases, whereas water storage tissue area significantly increases from Atraphaxis to Pteropyrum and Calligonum. This phenomenon confirms previous studies in other lineages with C4 salsoloid anatomy that have evolved through increasing of water storage tissue and succulence of assimilating organs. In the taxonomic part of the paper, a key to identification of accepted taxa of Pteropyrum , description of species and distribution maps are presented based on numerous herbarium specimens and our own rich collections from the field. Four new species are described based on a combination of morphology of seedlings and mature plants, pollen morphology and molecular data. A subspecific classification is suggested to show morpho-geographical variation of Pteropyrum aucheri s.l. [ABSTRACT FROM AUTHOR]

Asteraceae, the daisy family, are one of the most diverse families of angiosperms and are predominant in many ecosystems, including grasslands, deserts, savannas and high-elevation mountains. They are characterized by a peculiar inflorescence, the capitulum, which mimics a flower, but is actually made up of many tightly grouped florets. The capitulum is considered a key character underpinning the impressive evolutionary success of the family, and it plays a pivotal role in the economic importance of the family, given that many species are cultivated for their capitulum for agricultural and horticultural purposes. However, to date, there is still no comprehensive understanding of the extent of the morphological diversity of capitula across lineages of Asteraceae. This is mainly due to a lack of appropriate tools for describing such a complex and condensed structure. To address the problem, we present a protocol for characterizing the full diversity of capitula from any lineage of Asteraceae. This involves making a whole dissection of a capitulum from fresh material; it is simple and cost-effective and requires relatively easy-to-transport equipment meaning that it can be done during fieldwork. [ABSTRACT FROM AUTHOR]

Horsetails (Equisetum, Equisetaceae) are one of the oldest groups of vascular plants with a nearly continuous fossil record dating back to the Carboniferous. Only a few studies have addressed relationships among and within the extant members of this fern genus. We here present the first complete phylogenetic analysis of one or more samples of all extant species covering the full geographical range. Using three plastid loci, we evaluate species limits, taxon circumscription and inter-relationships. Several known hybrids were also included to confirm their parentage. All species for which we included multiple samples are found to form discrete groups, but many infraspecific taxa appear not to warrant recognition. We found strong support for the placement of E. bogotense as sister to the rest of the genus, supporting recognition of a third subgenus in Equisetum, described in this paper as E. subgenus Paramochaete. We have evidence for acceptance of additional species, E. braunii and E. xylochaetum. We accept the American E. praealtum as separate from E. hyemale and we tentatively recognize two varieties in E. ramosissimum. A nomenclatural checklist, including accepted taxa, synonymy and distributions, is provided. Two new combinations are made and 77 names are typified. [ABSTRACT FROM AUTHOR]

In 1993, a shrub with yellow flowers reminiscent of but obviously distinct from Turnera was found near Mabura Hill in central Guyana, which was recollected in 2000. This paper offers a morphological description including leaf and wood anatomy and pollen morphology in addition to a phylogenetic analysis based on plastid DNA. Thanks to these studies, the mysterious species can now be assigned a position within the larger context of Passifloraceae. Our molecular results also show that the 'unknown yellow', as the plant became informally known, belongs to Passifloraceae, in which it is well supported as sister to Turneroideae. It is here described as the new genus and species, Pibiria flava, and because it lacks several floral characters typically (but not universally) found in this subfamily (heterostylous, fused sepals/petals, adnation of the stamens to the calyx, presence of a corolla and clawed petals), we also propose a new subfamily, Pibirioideae, to accommodate it. [ABSTRACT FROM AUTHOR]

We expand the genome size (GS) database for Bromeliaceae, specifically for subfamily Pitcairnioideae, and verify whether GS can provide information on the diversification of the five genera in this subfamily. We also provide a phylogenetic perspective on GS evolution in the subfamily and reconstruct the ancestral state for this character. We show that the evolutionary path of GS from the origin of angiosperms to the origin of Pitcairnioideae agrees with the proportional model of GS evolution. Furthermore, we propose that the high phenotypic diversity that is found across Bromeliaceae and that is well represented in Pitcairnioideae is both correlated with high rates of GS evolution of the species and associated with a short period of diversification. The paper also highlights the value of flow cytometry as a rapid and reliable technique for generating GS data which can be analysed in conjunction with other molecular and morphological data to help elucidate patterns of evolution and phylogenetic relationships within this family. [ABSTRACT FROM AUTHOR]

This paper and this issue attempt to address how, when and why the phenomenal c. 100,000 species of seed plants in tropical America (the Neotropics) arose. It is increasingly clear that an approach focusing on individual major biomes rather than a single aggregate view is useful because of evidence for differing diversification histories among biomes. Phylogenetic evidence suggests that Neotropical-scale diversification patterns are structured more ecologically than geographically, with a key role for phylogenetic niche or biome conservatism. Lower geographical structure reflects the fact that long-distance dispersal, inferred from dated phylogenetic trees, has overcome many supposed dispersal barriers. Overall, high rates of species turnover as inferred from palaeontological and molecular data have been the hallmark of plant evolutionary dynamics in the Neotropics throughout the Cenozoic, with most extant species diversity post-dating the Mid- to Late Miocene, perhaps reflecting the conjunction of both global climatic changes and geological upheavals such as the Neogene uplift of the tropical Andes. Future studies of Neotropical diversification will be facilitated by taxonomically and genetically better sampled phylogenetic analyses, their integration with palaeontological, geological and ecological data, and improved methods to estimate biogeographic history and diversification dynamics at different spatial and temporal scales. Future biome-focused approaches would benefit greatly from better delimitation and mapping of Neotropical biomes. © 2012 The Linnean Society of London [ABSTRACT FROM AUTHOR]

This paper considers the context for science contributing to policy development and explores some critical issues that should inform science advocacy and influence with policy makers. The paper argues that the key challenges are at least as much in educating conservation scientists and science communicators about society and policy making as they are in educating society and policy makers about science. The importance of developing processes to ensure that scientists and science communicators invest in the development of relationships based on respect and understanding of their audience in both communities and amongst policy makers provides a critical first step. The objectives of the Global Strategy for Plant Conservation acknowledge the importance of developing the capacities and public engagement necessary to implement the Strategy, including knowledge transfer and community capacity building. However, the development of targets to equip institutions and plant conservation professionals to explicitly address the barriers to influencing policy development through knowledge transfer and integration require further consideration. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, [ABSTRACT FROM AUTHOR]

The Global Strategy for Plant Conservation (GSPC) was the first such effort under the Convention on Biological Diversity (CBD), and had gone through a 3-year process to reach the level of maturity that enabled it to be approved by consensus by all Governments present at the key session in The Hague in April 2002. It provided a model for subsequent CBD workplans, with targets, and undoubtedly contributed to the 2010 target of reducing the rate of biodiversity loss. In the event, few of the targets were achieved, because of numerous constraints at both policy and implementation levels. Even so, the GSPC stands as an important milestone in the global effort to conserve biodiversity. However, few plant scientists can be satisfied that the essential steps are being taken to ensure the conservation of plants, although, of course, plant scientists are only one part of the complex effort that will be required. This paper offers some suggestions that might be worth consideration, building on the basic principle in politics that a strong constituency is necessary to victory. In other words, although plant scientists play a crucial role, plant conservation is too important to leave in their hands alone; far broader support is required, including from the private sector, agriculture, forestry, trade, economics, tourism and even the military. Although botanical science provides a solid foundation, other branches of science are also important, ranging from anthropology to zoology. The legal profession also has important contributions to make (as well as the ability to hamper progress - for example through using issues such as access and benefit sharing to limit the exchange of genetic materials for even noncommercial use). 2010 was the United Nations Year of Biodiversity, and the GSPC targets reached their due date. It therefore seems timely to add some additional perspectives to the effort to update the GSPC. This paper suggests ways to reach a far broader constituency, provides tools to those who are expected to achieve the targets, and suggests ways to build a strong international constituency to conserve the world's botanical wealth. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, [ABSTRACT FROM AUTHOR]

Strong geographical isolation within the distribution of a species may result in differentiated lineages exhibiting conspicuous phenotypic differences. In the present paper, we investigate whether plastid and phenotypic variation is geographically structured within the Olea europaea complex in Macaronesia, which comprises three subspecies separated by oceanic barriers: maroccana (south-west Morocco), guanchica (Canary Islands) and cerasiformis (Madeira archipelago). Plastid variation showed a significant pattern of geographical structure (NST > GST = 0.56), because of the lack of shared haplotypes among subspecies and the presence of a single and private haplotype in the eastern Canary Islands. Such a clear molecular structure, however, was not reflected in a congruent pattern of phenotypic differentiation among taxa in leaf morpho-functional traits. Despite the substantial genetic differentiation observed between the subspecies from Madeira and the Canary Islands, they displayed both higher leaf size (leaf area) and specific leaf area (leaf surface area-to-mass ratio) than their continental counterparts, probably as a result of oceanic conditions in subtropical environments. Unlike most of the plant groups previously studied in the Macaronesian region, the lineages of Olea illustrate how low phenotypic differentiation can be also related to a clear molecular differentiation in oceanic island enclaves. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 162, 54–63. [ABSTRACT FROM AUTHOR]