Botanical Journal of the Linnean Society

Wearn, James A.; Chase, Mark W.; Mabberley, David J.; Couch, Charlotte

doi: 10.1111/boj.12031pmid: N/A

AbstractThe use of different and often outmoded systems for the arrangement of collections in botanic gardens and herbaria hampers international research because it makes finding the location of a specific genus and family unpredictable. Following a series of international workshops, intended to develop a set of widely accepted circumscriptions of vascular plant families, a European and Australian consortium, the Vascular Plant Classification Committee (VPCC), was formed in 2008 to address the challenge of harmonizing collections (of living and preserved material and associated literary archives) across Europe and Australia; this was envisaged as an ambitious first step towards a globally accepted alignment of family circumscriptions and the use of an accepted unified linear sequence. In 2009, agreement on this was reached among six of the largest European botanical organizations, a pioneering scientific and political accomplishment. Global acceptance of this arrangement is now beginning to gather pace. A network of organizations adopting this new classification and sequence (or intending to, when resources allow) is developing and now reaches across five continents. In this article, we outline the aims of and progress made by the VPCC, and acknowledge the resources required for the reorganization of large collections, with a particular focus on those at the Royal Botanic Gardens, Kew. The importance of a dynamic sequence, reflective of taxonomic changes, and the ways in which such changes can be incorporated into collections are discussed.

Bezeng, Bezeng S.; Savolainen, Vincent; Yessoufou, Kowiyou; Papadopulos, Alexander S. T.; Maurin, Olivier; van der Bank, Michelle

doi: 10.1111/boj.12030pmid: N/A

AbstractInvasive plant species are a considerable threat to ecosystems globally and on islands in particular where species diversity can be relatively low. In this study, we examined the phylogenetic basis of invasion success on Robben Island in South Africa. The flora of the island was sampled extensively and the phylogeny of the local community was reconstructed using the two core DNA barcode regions, rbcLa and matK. By analysing the phylogenetic patterns of native and invasive floras at two different scales, we found that invasive alien species are more distantly related to native species, a confirmation of Darwin's naturalization hypothesis. However, this pattern also holds even for randomly generated communities, therefore discounting the explanatory power of Darwin's naturalization hypothesis as the unique driver of invasion success on the island. These findings suggest that the drivers of invasion success on the island may be linked to species traits rather than their evolutionary history alone, or to the combination thereof. This result also has implications for the invasion management programmes currently being implemented to rehabilitate the native diversity on Robben Island.

Postigo-Mijarra, José Mª; Barrón, Eduardo

doi: 10.1111/boj.12035pmid: N/A

AbstractA study of the late early Miocene (Ramblian?–lower Aragonian) phytocoenosis of the La Rinconada mine (Ribesalbes-Alcora Basin, Province of Castellón, eastern Spain) led to the identification of 19 plant species showing mainly xeromorphic and/or sclerophyllous characteristics (three conifers and 16 dicotyledonous angiosperms). These plants mainly reflect the zonal vegetation that developed beyond the influence of the palaeolake known to have existed in the area. This vegetation was characterized by the presence of conifers, Pinus hepios and Juniperus section Sabina, associated with members of Anacardiaceae, Celastraceae, Fabaceae and Myricaceae, taxa that would have formed an evergreen forest with a shrubby component. These communities also included species adapted to life in damper environments, including Mahonia bilinica, Sophora assimilis, aff. Ormosia sp., ‘Sapindus’ falcifolius and aff. Dombeyopsis lobata. New information regarding the leaf characteristics of Pistacia miocenica and Sophora assimilis is provided. The inferred zonal vegetation indicates the presence of evergreen–deciduous forests adapted to seasonally dry conditions (PFT 9), similar to those described for other parts of the Iberian Peninsula and elsewhere in Europe. The richness and diversity of the La Rinconada mine deposits provide insight into the zonal vegetation of the Ribesalbes-Alcora Basin, increasing our knowledge of the characteristics and evolution of the vegetation of south-western Europe during the Miocene.

Slenzka, Anita; Mucina, Ladislav; Kadereit, Gudrun

doi: 10.1111/boj.12041pmid: N/A

AbstractIn Salicornia, morphology does not provide reliable diagnostic characters supporting the true extent of evolutionary divergence in the genus, and species concepts have been challenged by molecular analyses. Here, we report the results of an analysis of 91 accessions of the S. meyeriana complex from South Africa and Namibia using the measurements of 38 morphological traits and external transcribed spacer (ETS) sequence data. Morphological data were analysed using discriminant analysis, principal coordinate analysis and nonmetric multidimensional scaling. Phylogenetic divergence was compared with the geographical and ecological diversity of the sampled populations. Tree topology corresponds to geography and ecology, but not to morphology. Most clades have distinct distribution areas and ecological profiles related to tidal, supratidal or inland saline habitats. Salicornia probably diversified in habitats that have experienced regular fragmentation by marine transgression/regression cycles during the Pleistocene. We suggest that this radiation produced young, but genetically, geographically and ecologically well-defined lineages. The lack of morphological signal reveals the existence of cryptic species in Salicornia and demonstrates the necessity of using molecular data to define taxa in this genus. We propose the recognition of two subspecies in the S. meyeriana complex: S. meyeriana subsp. meyeriana and S. meyeriana subsp. knysnaensis.

Sommerville, Karen D.; Martyn, Amelia J.; Offord, Catherine A.

doi: 10.1111/boj.12021pmid: N/A

AbstractThe germination requirements of 19 herbs in the Australian Alps were investigated to determine which species may be sensitive to predicted climate changes. Seeds were subjected to factorial treatments of cold stratification for 0, 4, 8 and 12 weeks, followed by incubation at constant temperatures of 10, 15, 20 and 25 °C and alternating temperatures of 20/5 and 20/10 °C. Germination responses were used to identify stratification-dependent species, to classify dormancy and to determine optimum conditions for laboratory germination. Ordinal logistic regression was used to determine whether the duration of stratification required for ≥ 50% germination could be predicted by seed weight, seed length, embryo : seed ratio or species distribution (latitudinal range, altitudinal range and maximum altitude). The Kruskal–Wallis test was used to determine any significant differences in stratification requirement between endospermic and non-endospermic seeds. Species varied considerably in their response to the treatment combinations, and therefore their dormancy class. No significant predictors of stratification requirement were identified by ordinal logistic regression (P > 0.9); however, there was a significant difference in stratification requirement between endospermic and non-endospermic seeds (P = 0.003). Species with non-endospermic seeds did not require any stratification to germinate well over a range of temperatures, and appear most likely to remain stable or expand in range in response to climate warming. Conversely, the need for ≥ 8 weeks of cold stratification was associated with the presence of endosperm and either a restricted distribution or upland ecotypes of widely distributed species. Alpine species with endospermic seed and a restricted distribution are most likely to contract in range under climate change and would be appropriate to prioritize for ex situ conservation.

Niketić, Marjan; Siljak-Yakovlev, Sonja; Frajman, Božo; Lazarević, Maja; Stevanović, Branka; Tomović, Gordana; Stevanović, Vladimir

doi: 10.1111/boj.12050pmid: N/A

AbstractAnalyses of mitotic chromosome numbers and nuclear DNA content were performed for 39 populations of 17 perennial Cerastium taxa from south-eastern Europe. The DNA content ranged from 2C = 2.43 to 8.78 pg, revealing four ploidy levels corresponding to 4x (2n = 36), 8x, 12x and 16x. High-polyploid cytotypes with a greater range of ploidy (up to 2n = 144) occur mostly in the central mountainous parts of the Balkan Peninsula. The chromosome number was determined for the first time for C. dinaricum (2n = 36 + 1B), C. decalvans subsp. orbelicum (2n = 36), C. decalvans subsp. glutinosum (2n = 36), C. neoscardicum (2n = 144), C. malyi subsp. serpentini (2n = 144) and C. moesiacum s.s. (2n = 144). New chromosome counts were recorded for C. arvense subsp. strictum (2n = 108), C. banaticum subsp. kosaninii (2n = 36) and C. grandiflorum (2n = 36). For the first time, flow cytometry was used to estimate C values for six species (15 taxonomic entities). The intraspecific variation quotient of C values is high, ranging from 1.003 in C. malyi to 1.306 in C. decalvans subsp. decalvans. The variation in chromosome size among both tetra- and octoploid members of Cerastium is much more prominent than in most other angiosperm polyploid series. Significant genome downsizing after polyploidization was observed in some investigated taxa. Differences in ploidy levels and monoploid genome size values confirm the taxonomic status of C. decalvans subsp. glutinosum and C. decalvans subsp. leontopodium. The results obtained indicate a possible close relationship between C. banaticum and C. grandiflorum, but not C. arvense.

Wachowiak, Witold; Boratyńska, Krystyna; Cavers, Stephen

doi: 10.1111/boj.12049pmid: N/A

AbstractNucleotide polymorphism at 12 nuclear loci and two mitochondrial gene fragments was studied in three closely related pine species from the Pinus mugo complex in populations across the species distributional range in Europe. Despite large differences in the census sizes of the populations, high and similar levels of nucleotide diversity (θsil = ∼0.013–0.017) were found at nuclear loci in the three pine species. More rapid decay of overall linkage disequilibrium (LD) and recombination to diversity ratio (ρ/θ) was observed across the species distributional range in P. mugo (ρ = 0.0369 ± 0.0028; ρ/θ = ∼2.2) than in P. uncinata (ρ = 0.0054 ± 0.0011; ρ/θ = ∼0.4) and P. uliginosa (ρ = 0.0051 ± 0.0010, ρ/θ = ∼0.4). However, regional groups of P. mugo showed similar levels of LD and ρ/θ ratio to the other species. An excess of rare nucleotide variants was found in P. mugo at four loci, but, overall, the allelic frequency spectrum in the three species did not deviate significantly from neutrality (multilocus Tajima's D = −0.681, D = −0.118 and D = −0.266, P > 0.05, respectively). Bayesian clustering methods showed no clear correspondence of clusters to species or geographical regions. Some differences between populations and species were found in a hierarchical analysis of molecular variance (AMOVA) and in the distribution of the mitochondrial DNA haplotypes, suggesting rather limited gene flow between the taxa and ongoing divergence. As all three pine taxa have similar genetic backgrounds, they form an excellent system for searching for loci involved in adaptive variation and speciation.

Kalle, Raivo; Sõukand, Renata

doi: 10.1111/boj.12051pmid: N/A

AbstractIn this ethnobotanical study, the authors provide the first quantitative analysis of the use of wild edible plants in Estonia, describing the domains and assessing the food importance of different species. The information was collected using free-listing written questionnaires and concerned plants used by the respondents in their childhood. As part of a major study, this article covers the responses of professionals with some botanical education at vocational or university level, to ensure the greatest possible reliability without using voucher specimens. Fifty-eight respondents provided information on the use of 137 plant taxa, corresponding to approximately 6% of the native and naturalized vascular plants of Estonia. According to use frequency, the most typical wild food plant of Estonia is a fruit, eaten raw as a snack. The results clearly signal that the majority of famine and food shortage plants had already been forgotten by the end of the 20th century, but new plants have been introduced as green vegetables for making salads. Despite changes in the nomenclature of the plants, the use of wild food plants in Estonia was still thriving at the turn of the 20th century, covering many domains already forgotten in urbanized modern Europe.