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The article examines the molecular evidence resolving the systematic position of Hectorella or portulacaceae. According to the article, the taxonomic position of Hectorella caespitosa and Lyallia kergelensis are endemic to New Zealand and to the Kerguelen Archipelago of Antarctica. Hectorella's characteristics include sieve-element plastids similar to those of Portulacaceae, wood anatomy resembling to that of Lewisia and the ability to produce betalain pigments.

The current classification of Ptelea divides the widespread and highly variable Ptelea trifoliata L. into 5 subspecies and 11 varieties, while additionally terming many specimens "intermediate." Although there are visually observable differences among regional variants, principal component analyses of quantitative characters failed to separate subspecies or to even incompletely separate most varieties within subspecies. Some recognized subgroups are also not well distinguished by discontinuous qualitative characters. Where multiple varieties appear to be part of a single continuum of variation or are extremely similar, it is suggested that a reduction in the number of infraspecific taxa would improve the utility of the classification. An alternative classification recognizing 5 subspecies and 7 varieties is accordingly proposed. [ABSTRACT FROM AUTHOR]

Background and Aims The largest genus of Salicaceae sensu lato , Salix , has been shown to consist of two main clades: clade Salix , in which species have XY sex-determination systems (SDSs) on chromosome 7, and clade Vetrix including species with ZW SDSs on chromosome 15. Here, we test the utility of whole genome re-sequencing (WGR) for phylogenomic reconstructions of willows to infer changes between different SDSs. Methods We used more than 1 TB of WGR data from 70 Salix taxa to ascertain single nucleotide polymorphisms on the autosomes, the sex-linked regions (SLRs) and the chloroplast genomes, for phylogenetic and species tree analyses. To avoid bias, we chose reference genomes from both groups, Salix dunnii from clade Salix and S. purpurea from clade Vetrix. Key Results Two main largely congruent groups were recovered: the paraphyletic Salix grade and the Vetrix clade. The autosome dataset trees resolved four subclades (C1–C4) in Vetrix. C1 and C2 comprise species from the Hengduan Mountains and adjacent areas and from Eurasia, respectively. Section Longifoliae (C3) grouped within the Vetrix clade but fell into the Salix clade in trees based on the chloroplast dataset analysis. Salix triandra from Eurasia (C4) was revealed as sister to the remaining species of clade Vetrix. In Salix , the polyploid group C5 is paraphyletic to clade Vetrix and subclade C6 is consistent with Argus's subgenus Protitea. Chloroplast datasets separated both Vetrix and Salix as monophyletic, and yielded C5 embedded within Salix. Using only diploid species, both the SLR and autosomal datasets yielded trees with Vetrix and Salix as well-supported clades. Conclusion WGR data are useful for phylogenomic analyses of willows. The different SDSs may contribute to the isolation of the two major groups, but the reproductive barrier between them needs to be studied. [ABSTRACT FROM AUTHOR]

Recent collections of vascular plants on the Crow Creek Indian Reservation in central South Dakota include 64 new county records for Hughes County, 72 for Buffalo County, and 1 for Hyde County. Additionally, 2 new county records are reported for Sioux County in southern North Dakota. [ABSTRACT FROM AUTHOR]

Madagascar is well-known for the exceptional biodiversity of its macro-flora and fauna, but the biodiversity of Malagasy microbial communities remains relatively unexplored. Understanding patterns of bacterial diversity in soil and their correlations with above-ground botanical diversity could influence conservation planning as well as sampling strategies to maximize access to bacterially derived natural products. We present the first detailed description of Malagasy soil bacterial communities from a targeted 16S rRNA gene survey of greater than 290,000 sequences generated using 454 pyrosequencing. Two sampling plots in each of three forest conservation areas were established to represent different levels of disturbance resulting from human impact through agriculture and selective exploitation of trees, as well as from natural impacts of cyclones. In parallel, we performed an in-depth characterization of the total vascular plant morphospecies richness within each plot. The plots representing different levels of disturbance within each forest did not differ significantly in bacterial diversity or richness. Changes in bacterial community composition were largest between forests rather than between different levels of impact within a forest. The largest difference in bacterial community composition with disturbance was observed at the Vohibe forest conservation area, and this difference was correlated with changes in both vascular plant richness and soil pH. These results provide the first survey of Malagasy soil bacterial diversity and establish a baseline of botanical diversity within important conservation areas. [ABSTRACT FROM AUTHOR]

Black cohosh [Actaea racemosa L.; Cimicifuga racemosa (L.) Nutt.] is a perennial herb native to North America that is commonly used for the treatment of menopausal symptoms. The plant is almost exclusively harvested from the wild and is being threatened by overharvesting in some regions. As demand for this plant continues to increase, the potential for profitable cultivation of this species is becoming realistic. Little is known about the effect of various cultivation practices, soils, environments, and harvest times on the multitude of phytochemicals that occur in black cohosh. Furthermore, although the rhizome is the organ that is traditionally consumed, other tissues also contain various quantities of important phytochemicals, but this has not been well documented. The objectives of this study, therefore, were to ascertain any environmental effects on the production of two representative phytochemicals (23-epi-26-deoxyactein and cimiracemoside A) and to elucidate any season-long patterns or variations in the production of these compounds within five black cohosh tissues (leaf, rachis, rhizome, root, and inflorescence). All black cohosh tissues contained 23-epi-26-deoxyactein with substantially more, as a percentage of dry weight, detected in inflorescence (28,582 to 41,354 mg⋅kg-1) and leaf (8250 to 16,799 mg⋅kg-1) compared with rhizome (2688 to 4094 mg⋅kg-1), and all tissues experienced a linear season-long decrease in occurrence of this compound. Cimiracemoside A was not detected in leaf tissues. The highest levels were found in rhizome (677 to 1138 Mg⋅kg-1) and root (598 to 1281 mg⋅kg-1), which likewise experienced a significant season-long decrease in this compound, whereas levels in the rachis (0 to 462 mg⋅kg-1) increased over time. in general, environmental factors did not affect production of either compound. Varying seasonal patterns in phytochemical production, combined with differences in phytochemical content among plant tissues, point to the potential for more targeted horticultural production of these and other medicinal compounds within black cohosh. [ABSTRACT FROM AUTHOR]

Black cohosh [Actaea racemosa L, Cimicifuga racemosa L. (Nutt)] is a perennial herb commonly used for treatment of menopausal symptoms in humans. The increasing demand for this plant is leading to serious over-harvesting from the wild and presents an opportunity for potentially profitable cultivation. The plant produces a large rhizome, the principal medicinal organ, which appears to be especially sensitive to heavy soil, and prone to fungal attack if soil water drainage is not adequate. After an earlier crop failure (attributed to a Phytophthora-Pythium disease complex) in an established black cohosh nursery bed, two experiments were conducted in the same soil to determine if certain horticultural approaches could help to avert fungal infection under less-than-ideal conditions. Treatments included single postplanting applications of the fungicide mefenoxam, transplantation in fall versus spring, and shallow (0.5 cm) versus deep (6.5 cm) placement of rhizomes. Shallow placement significantly improved long-term rhizome survival, but was still not able to compensate adequately for a poorly-drained soil. The horticultural approaches we studied do not appear to be reliable alternatives to proper site selection in the cultivation of black cohosh. [ABSTRACT FROM AUTHOR]