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The in-vitro culture of arbuscular mycorrhizal fungi on excised roots, especially when performed on bi-compartmented Petri dishes, has proven to be an efficient system for the production of root-free fungal material. However, even after the contact between fungal hyphae and the excised roots in the proximal root compartment has occurred, up to several weeks may be required for the fungal runner hyphae to cross the median Petri dish wall and reach the distal fungal compartment. This delay is particularly long for the cultivation of slow-growing strains that usually colonize the substrate less aggressively. The delay is due to the difficulty the runner hyphae have in crossing the median Petri dish wall that separates compartments. To facilitate the passage of the fungus across the median wall, a “paper bridge” system has been devised and tested with a number of arbuscular mycorrhizal fungal strains. This method substantially accelerated fungal propagation and simplified the manipulations necessary. The proposed paper-bridge system is described and its advantages discussed. La culture in vitro des champignons mycorhiziens arbusculaires sur racines excisées, notamment en boîtes de Petri bi-compartimentées, constitue un système efficace de production axénique de champignon. Bien que le contact hyphe-racines s’effectue rapidement dans le compartiment racine, plusieurs semaines peuvent être requises par les hyphes pour traverser dans la partie distale du système. Ce délai, particulièrement long pour les souches à croissance lente et peu agressives, est dûprincipalement à la difficulté pour les hyphes de traverser la cloison centrale qui sépare les compartiments. Afin de remédier à cette difficulté un « pont de papier » testé sur une diversité de souches mycorhiziennes s’est avéré efficace pour accélérer la propagation fongique tout en simplifiant substantiellement les manipulations. Le système est décrit et ses avantages discutés. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses articles in the issue on topics including dwarf mistletoes, research papers and pathogenic microorganisms.

The Miyawaki method, developed by Akira Miyawaki, restores natural forests by planting diverse native species in compact spaces, rapidly creating compact, resilient ecosystems. Initially successful in Japan, its global application bloomed but remains rare in Mediterranean urban areas despite benefits like biodiversity enhancement and climate change mitigation. This method's effectiveness in Mediterranean climates, which face unique challenges like urban heat islands and biodiversity loss, is underexplored in literature and practice. We are leading a project in Italy to identify optimal plant assemblages, addressing the method's documentation gap in urban settings. It explores the potential of Tiny Forests to provide ecosystem services and improve urban liveability against climatic extremes. This note paper details the methodological steps undertaken in this experimental application, offering a tailored approach to test the method's adaptability and impact in Mediterranean urban environments, suggesting a significant opportunity for urban greening and resilience. [ABSTRACT FROM AUTHOR]

The article presents information on the paper awards presented by the journal "Botany," where the journal recognizes the works of students and professors in different fields of study. The J. Stan Rowe award is presented to the students in the field of plant ecology and the Taylor A. Steeves award is presented students with botany as a subject. Information on the eligibility that includes the bona fide of the students and the evaluation of the students is also presented.

An introduction is presented in which the editor discusses articles in the issue on topics including dwarf mistletoes, research papers and pathogenic microorganisms.

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An introduction is presented in which the editor discusses articles in the issue on topics including Parasitic Flowering Plants in Forests, Focus on a Holoparasite, Two Common Mycoheterotrophs in Northern Temperate Forests, and other related topics.

Three species of Candolleomyces D. Wächt. & A. Melzer (Agaricomycetes, Psathyrellaceae) were identified in the course of our studies to characterize the psathyrelloid fungi of Kerala state, India. Among these, two species, e.g., Candolleomyces brunneopileatus and Candolleomyces niveofloccosus, are new to science, while Candolleomyces asiaticus represents a new Indian record. Detailed descriptions, photographs, and comparison of these species are provided based on morphology and molecular data. A phylogenetic reconstruction based on maximum likelihood analyses of a combined nrITS and nrLSU sequence is also provided. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Understanding the mechanisms underlying species' distribution limits is critical for predicting how species may respond to environmental change. For species restricted to mountain summits, there is concern that climatic changes may result in increasingly restricted distributions. Two central mechanisms govern species distribution limits: (i) niche limitations–environmental conditions beyond distribution limits that are insufficient for survival and reproduction, and (ii) dispersal limitations that prevent colonization of suitable habitat beyond distribution limits. Here, we conducted a transplant experiment to examine the effect of niche versus dispersal limitation on the altitudinal distribution limit of the Ghost Antler Lichen (Pseudevernia cladonia (Tuck.) Hale & Culb.) that, within Québec, Canada, is restricted to high-elevation mountain summits in the southeast. Along an elevation gradient, we transplanted individuals into sites within its distribution, at the edge, and beyond its distribution. We observed that survival and performance were greatest within its distribution and decreased markedly beyond its distribution, supporting our prediction that this lichen is niche limited along the elevation gradient. We suggest that cooler and more humid conditions at the summit are important environmental factors for this species' persistence. Our findings suggest that projected climatic changes in these montane habitats may result in less suitable habitat for this species. [ABSTRACT FROM AUTHOR]

In the USA, road salt usage in urban areas has increased since the 1950s. In the greater Chicago area over 175 000 tons of salt are applied every year. The salt runoff from this application has the potential to negatively impact nearby plants and alter native plant communities. We evaluated how varying salt concentrations affect overall germination, germination probability, and multiple metrics of germination speed for seeds from five source populations of Thuja occidentalis L. Two populations in a native forested fen system are susceptible to salt runoff from the Illinois Tollway. We found that increased salt concentrations decreased both the probability of germination and overall germination, and increased the time to germination. Seeds from the two natural populations performed poorly compared to the other populations. Salt pollution impacts the health and survival of adult trees, and may also inhibit the reproduction and recruitment of T. occidentalis. Reduction of salt pollution is necessary to maintain the long-term survival and persistence of this species, other sensitive species, and native fen habitats. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Carex dianae Steud. is an endemic sedge of St. Helena, an isolated island in the South Atlantic. Our study provides the first molecular sequence data for this taxon. We generated sequence data for plastid matK and trnK regions and nuclear internal transcribed spacer and external transcribed spacer regions to determine the placement of C. dianae in the broader Carex phylogeny. The placement of C. dianae falls within Carex sect. Spirostachyae Drejer, and it is sister to a clade including Carex clavata Thunb., Carex aethiopica Schkuhr (both from the Cape region of S. Africa), and Carex gunniana Boott (southern Australia). The existence of three divergent nucleotype groups and two plastotypes is revealed from genetic variation within C. dianae. The results suggest that the ancestor of C. dianae likely originated in the Cape region of South Africa, followed by transoceanic dispersal to St. Helena estimated at 4.4–4.9 million years ago, likely by a bird vector. The most divergent population is that on an isolated hill known as "The Barn", which may represent a distinct taxon. The existence of highly structured molecular variation within an island only 16 km long is discussed. [ABSTRACT FROM AUTHOR]

A physiological and metabolic database for various species of Amazonian plants is crucial to the species selection and sustainable utilization of their diversity. We hypothesized that understanding the mobilization of Carapa seed reserves and water uptake during germination could provide insights into the physiological behavior and propagation to differentiate species of the same genus. Given this, the mobilization mechanisms of primary reserves, water uptake, and enzymatic activities in seeds of two species of Carapa (Carapa guianensis and Carapa vasquezii) were investigated. The lipid content was high in both species, with a value of 63.7 ± 4.7% for C. guianensis and 55 ± 1.5% for C. vasquezii. Carapa guianensis showed higher values for the other evaluated reserves. The protein profile highlights a band between 15 and 25 kDa in C. guianensis. As for the enzymatic activities investigated (lipase, amylase, protease, amd acid phosphatase), C. guianensis showed greater activity for most of them, except for acid phosphatase. Overall, the species showed different metabolic strategies and dynamics regarding the water uptake and use of reserves. Our findings indicate that distinct metabolic pathways are employed during the germination and initial seedling growth stages of two Carapa species. This trait can potentially guide the use and conservation of these species. [ABSTRACT FROM AUTHOR]

Crassocephalum rubens, a herb with potential anticancer properties, encounters challenges in production efficiency due to small seed size and elevated temperatures in cultivation areas. Our study investigates the effects of seed pelleting and plant growth-promoting bacteria (PGPB) on germination and seedling growth across temperature variations in Taiwan. Pelleted seeds demonstrate superior germination percentages linked to enhanced seed quality. Elevated temperature, particularly at 30/25 °C, enhanced germination performance, with the highest final germination percentage observed in pelleted seeds treated with water. Unexpectedly, PGPB strains—Klebsiella sp. KsGRB10 and Bacillus sp. BsGFB04—exhibited limited impact on germination rates, showing a marginal increase in seedling growth under 25/20 °C and 30/25 °C, respectively. Air temperature fluctuations influenced seedling vigor, leaf color, and physiological parameters. Remarkably, inoculation with BsGFB04 and KsGRB10 enhanced C. rubens' tolerance to high-temperature stress conditions. Diurnal measurements in week 4, under 25/20 °C, reveal that PGPB inoculation decreased stomatal conductance and transpiration rate while maintaining the quantum yield of PSII, indicating potentially improved water-use efficiency. This study provides crucial insights into the interplay among PGPB, environmental stress, and the physiology of a wild species, paving the way for further research in the domestication of C. rubens for medicinal herb mass production. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Understanding patterns of variation in functional traits of hardwood trees is crucial for conserving and managing North American temperate forests under climate change. This study examined provenance variation of yellow birch (Betula alleghaniensis Britton) in growth, biomass allocation, leaf morphology, and stable carbon isotope composition. Trees were grown from 10 seed sources originating from across Canada and the northern USA. Height and diameter were not significantly related to climate at seed origin, suggesting that variation may be better explained by site factors, such as soil pH and soil moisture. In contrast, carbon isotope composition and leaf morphological traits were significantly correlated to climate variables including temperature, precipitation, and solar radiation. Provenances from warmer, drier localities tended to have higher stable carbon isotope ratio (δ13C), greater specific leaf area, and narrower leaf width than their counterparts from cooler, wetter climates. Thus, variation in leaf morphological traits appears to be involved in adaptation of yellow birch to variation in temperature and moisture availability across the species' range. Our results suggest that there may exist potential for selection and breeding of drought-resistant yellow birch genotypes to aid in reforestation under climate change. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The bryological history of Washington State, USA, is scattered and not well organized. An overall study of the moss flora within the San Juan Islands led to extensive searches of the major regional herbaria and a review of the relevant literature. This paper provides the foundation for a complete bryophyte history and moss flora of the state and reports new records of three species, Drepanocladus crassicostatus Janssens, Orthotrichum hallii Sull. & Lesq. in Sull., and Syntrichia papillosa (Wilson) Jur., and one variety, Syntrichia laevipila Brid. var. meridionalis (Schimp.) Wijk & Marg., for Washington. Les documents historiques sur la bryologie de l’état de Washington aux tats-Unis, sont dispersés et mal organisés. Une étude sur l’ensemble de la flore muscinale des îles San Juan a fourni l’occasion d’examiner les principaux herbiers régionaux et de revoir la littérature pertinente. Cette publication constitue la base pour construire une histoire complète des bryophytes et la flore muscinale de l’état et rapporte de nouvelles mentions pour trois espèces, les Drepanocladus crassicostatus Janssens, Orthotrichum hallii Sull. & Lesq. in Sull., et Syntrichia papillosa (Wilson) Jur., et une variété, le Syntrichia laevipila Brid. var. meridionalis (Schimp.) Wijk & Marg., pour Washington. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The taxonomic classification of dwarf mistletoes (Arceuthobium spp., Viscaceae) in series Campylopoda requires a multi-trait approach, integrating plant genetics, morphologies, and phenologies as well as their host and geographic distributions. Thus, competing interpretations on the contribution of these traits to defining species and subspecies boundaries has spurred considerable debate. Accordingly, the recent reclassification of 12 previously recognized species in ser. Campylopoda to separate subspecies of Arceuthobium campylopodum in the Flora of North America (FNA) has furthered this debate. We contend that these taxa deserve separate species recognition, while subspecies described prior to and after the recombination of ser. Campylopoda taxa in the FNA also deserve recognition. Herein, we provide evidence that the treatment in the FNA does not adequately reflect the diverse morphological, geographic, host, and phenological differences across the series, and hence, we maintain that the reclassification of ser. Campylopoda taxa was not justified according to empirical evidence published prior to and following the FNA treatment. We conclude our critique of the FNA treatment of ser. Campylopoda by advocating for the continued application of the Hawksworth and Wiens' classification system, with minor modifications to the constitution of the series. [ABSTRACT FROM AUTHOR]

Mistletoe detection and sampling remain challenging for arborists, dendrologists, forest ecologists, and other specialists because of the limited access to host tree canopy. In this review, smart solutions for mistletoe detection based on airborne platforms are discussed. Airborne remote sensing (ARS) has the developing potential to provide rapid, accurate, and cost-efficient detection and research of mistletoe on tree level and large areas within the complex terrain. Herein, such mistletoe ARS research methods as image spectroscopy, infrared thermography, light detection and ranging, and structure from motion are overviewed. [ABSTRACT FROM AUTHOR]

Herbaceous layers in second-growth forests are shaped by past land use. Disturbances such as agriculture may impact populations of mycoheterotrophs, non-photosynthetic mycorrhizal plants that obtain carbon from fungal networks by altering mycorrhizal communities or removing trees they derive carbon from. I tested the hypotheses that two mycoheterotrophic forest herbs increase in abundance during succession and become most common in older forests as plant communities reassemble through time. Distributions of Hypopitys monotropa and Monotropa uniflora were sampled in Athens County, Ohio, USA. I surveyed populations in a 40-site post-agricultural forest chronosequence with five upland and five valley sites in each of four age classes: 40–60, 61–80, 81–100, and >130 years since canopy closure. Aspect and elevation were measured to assess environmental influence. Both H. monotropa and M. uniflora were most common in older stands with EM tree-rich canopy composition and west- or south-facing aspects, indicating influence of historical, biotic, and edaphic factors. Hypopitys was exclusive to forests >80 years old, while M. uniflora was present in younger stands. Abundance of both species was also significantly predicted by Fagaceae basal area. Because EM trees were also most abundant in south- and west-facing uplands, environmental influence appears to be mediated through canopy composition. [ABSTRACT FROM AUTHOR]

Mistletoes are parasitic plants that largely rely on animals for pollination and seed dispersal but establish complex interactions with their host plants. Mistletoes are considered keystone species in forest ecosystems as they facilitate several interactions. We studied the fauna associated with two sympatric mistletoe species (Tristerix corymbosus (L.) Kuijt and Desmaria mutabilis (Poepp. & Endl.) Tiegh.) from the temperate rainforests of southern Chile. We set 40 camera traps from November 2021 to May 2022 to monitor the main pollinator (the hummingbird Sephanoides sephaniodes (R. Lesson & Garnot, 1827)), the main seed disperser (the arboreal marsupial Dromiciops bozinovici D'Elía, Hurtado & D'Anatro, 2016), and other animals (birds, mammals, reptiles, and insects). We compared fauna associated with Tristerix corymbosus between spring and summer–fall periods and between Tristerix corymbosus and Desmaria mutabilis during summer–fall. Species composition associated with Tristerix corymbosus showed a significant temporal variation, mainly explained by Sephanoides sephaniodes and Dromiciops bozinovici, which are more abundant in the summer–fall period. We found that animal species composition differences between mistletoe species were mainly explained by S. sephaniodes, Dromiciops bozinovici, and insects. While Tristerix corymbosus was mainly pollinated by hummingbirds, insects frequently visited Desmaria mutabilis flowers. Although both mistletoes have many similarities, they also have some phenology differences that affect their associations with animals, potentially influencing ecological processes. [ABSTRACT FROM AUTHOR]

Fruits of Psittacanthus (Loranthaceae) mistletoes depend on frugivorous birds for seed dispersal; however, despite the importance of birds in their dispersal and distribution, the external fruit morphology and anatomy and seedling remain poorly studied. Here, we describe the fruit anatomy and seedling of host generalist Psittacanthus schiedeanus (Cham. & Schltdl.) G. Don (Loranthaceae), a mistletoe species occurring from Mexico to Panama. Fully developed unripe fruits and ripe fruits were collected, processed for microphotography, and examined to describe fruit external morphology and anatomy. The following parts were observed in fruits: exocarp, viscin layer, seed coat, and the polycotylous embryo. Longitudinal sections also show the inverted position of the embryo. The fruits of Psittacanthus schiedeanus contain a polycotylous embryo and no endosperm. The absence of endosperm in the mature seed and the massive cotyledons having the storage function for the germinating seedling await further Psittacanthus species comparisons to end the pretending controversy of the polycotylous embryo and between having or not having endosperm in Psittacanthus. [ABSTRACT FROM AUTHOR]

Despite bryophytes being well adapted to various ecological settings, they are rarely considered in reclamation projects. In this study, propagation regenerative capabilities of bryophytes on different substrates (sand, amphibolite, and pegmatite) and conditions (with or without peat amendment, shade and shredding) were tested in greenhouse and field experiments. In the greenhouse trial, after 6 months of reintroduction, Racomitrium species (Racomitrium canescens (Hedw.) Brid. and Racomitrium elongatum Frisvoll.) had higher regeneration compared to Polytrichum species (Polytrichum juniperinum Hedw. mixed with Polytrichum piliferum Hedw.; a combination of shade (65% shading) and peat amendment (0.5 cm depth) was found to be particularly effective, resulting in up to 100% of Racomitrium species regeneration; shredding the stems of Polytrichum species into small pieces of 0.5–1.0 cm inhibited its regeneration. In the field trial, peat amendment had no effect on moss regeneration. The addition of fluvioglacial sand or till on waste rocks promoted bryophytes regeneration in both the greenhouse and field. These results provide science-based practical knowledge to support the inclusion of native bryophytes in waste rock restoration plans for mines located in northern boreal forests. [ABSTRACT FROM AUTHOR]

Riverine macrophytes are increasingly understood to influence both the physical and chemical dynamics of rivers by creating biogeochemical hotspots and stabilizing benthic sediments. They contribute carbon and nutrients to both aquatic and adjacent terrestrial ecosystems through senescence and herbivory. Here, we report the relationships between Justicia americana biomass, stem length, and stem density, and % carbon (%C), % nitrogen (%N), C:N, δ15N, and δ13C relationships between tissues types (roots, stems, and leaves). Additionally, we report the effects of land use on the plant's tissue. We found that (1) J. americana stem density and dry biomass were positively correlated (P < 0.001); (2) δ13C and %N were significantly different in leaf and root tissue; (3) δ13C and δ15N were both positively correlated across tissue types; (4) Leaf C:N was less than ½ of root and stem tissue; (5) %C in leaf tissue was positively correlated (P < 0.05) with forest cover and negatively correlated with urbanization and watershed area; and (6) provide evidence that J. americana utilizes a C3 photosynthetic pathway. Overall, this study provides novel insight into the ecology of J. americana by elucidating the nutritional quality of different plant tissues and stoichiometric changes in the plant in response to land use. [ABSTRACT FROM AUTHOR]

Species-focused conservation requires a thorough understanding of species' distributions. Delineating a species' distribution requires taxonomic knowledge and adequate occurrence data. For plants and fungi, herbaria represent a valuable source of large-scale occurrence data. Advances in digital technology mean that data from many herbarium collections worldwide are now easily accessible. However, species concepts can change over time requiring herbarium records to be re-examined and databases updated, which does not always occur synchronously across all collections. Therefore, non-critical use of these data can promote inaccuracies in understanding species distributions. Taxonomic revisions are common in understudied organisms, such as lichens. Here, we illustrate how changing taxonomy and non-critical acceptance of online data affects our understanding of disjunct distributions, using the lichen Brodoa oroarctica (Krog) Goward as an example. Defining the distribution of the arctic lichen B. oroarctica is confounded by changing taxonomy and uncertainty of herbarium records that pre-date taxonomic revisions. We review the distribution of this species in the literature and in aggregate occurrence databases, and verify herbarium specimens that represent disjunct occurrences in eastern North America to present an updated account of its distribution and frequency in eastern North America. We show that knowledge of changing species taxonomy is essential to depicting accurate species distributions. [ABSTRACT FROM AUTHOR]

In species that primarily reproduce asexually, occasional sex can have important evolutionary consequences. Many plant species in the genus Oenothera have a genetic system called permanent translocation heterozygosity (PTH), which renders plants functionally asexual when they self-fertilize. PTH results from reciprocal translocations of chromosomes that suppress recombination and a balanced lethal mortality of homozygous gametes that prevents independent assortment of alleles. When PTH plants self-fertilize, the offspring are genetically identical to the parents, but when they outcross they can create new genotypes. Here, we sought to determine the outcrossing rate of natural populations of PTH Oenothera biennis L. (Onagraceae). We genotyped 46 parents from 14 populations in Tompkins County, NY, USA, and 754 of their offspring at highly polymorphic microsatellite loci. 99.5% of offspring were genetically identical to their seed parents, whereas 4 offspring out of 754 exhibited allelic mismatches with their seed parent. The estimated outcrossing rate ranged from 0.1% to 0.4%. Our study design also permitted us to estimate mutation rate of microsatellite loci, which ranged from 1.33 × 10−3 to 3.98 × 10−3. These results show that O. biennis typically exhibits a functionally asexual genetic system, but rare outcrossing events can generate novel genotypes that may have important evolutionary consequences. [ABSTRACT FROM AUTHOR]

The article discusses papers on ethnobotany in Canada published within this issue, including one on traditional nutritional knowledge and another on the traditional use of plants for medicine in the Arctic.

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An introduction is presented in which the editor discusses articles in the issue on topics including mistletoe, ecosystems, and people.

Lactifluus subg. Lactariopsis is a well-supported group of milkcaps occurring predominantly in tropical and subtropical ecosystems. This subgenus contains agaricoid and pleurotoid representatives and is the only group with members containing a secondary velum. The results of taxonomic and phylogenetic research into Lactifluus subg. Lactariopsis collected in Brazilian tropical forests (Amazon, Atlantic Rainforests, and Caatinga biomes) of the North and Northeast is presented here. Two new species are described: Lf. aurantioceraceus in sect. Neotropici, and Lf. reniformis in sect. Multicipites, newly delimited here. In addition, Lf. neotropicus has had its distribution expanded to the Caatinga biome, Lf. dunensis was confirmed in Lf. sect. Neotropici with new records from French Guiana, and Lf. annulifer was re-collected from the type locality. A combined dataset of nuclear rDNA internal transcribed spacer region and nuclear large subunit amplified sequences was analyzed and, based on its phylogenetic hypothesis, the two novel taxa and the new section were confirmed. [ABSTRACT FROM AUTHOR]

Picea × darwyniana Björk & Goward was recently proposed to replace Picea albertiana S. Brown as the representative taxon for the hybrid offspring of Picea glauca (Moench) Voss and Picea engelmannii Parry ex Engelm., but should be considered invalid for three reasons. First, the proponents failed to document in any way that the P. albertiana isotypes were Picea glauca × mariana Little & Pauley hybrids, as they claimed. Secondly, the P. albertiana isotypes lacked pubescent twigs, purple markings on their seed cones, and denticulate cone-scale margins, which are characteristics of P. glauca × mariana. This indicates a misinterpretation of the P. albertiana parentage. Lastly, P. × darwyniana appears to be an example of P. albertiana ssp. ogilviei Strong & Hills. As the latter is an earlier and validly published name, P. × darwyniana is an illegitimate replacement for plants within the P. glauca × engelmannii (=P.a. ssp. albertiana) and P. engelmannii × glauca (=P.a. ssp. ogilviei) circumscriptions based on naming priority. [ABSTRACT FROM AUTHOR]