6 research outputs found
Passiflora Subgenus Astrophea
This paper examines an unusual group of Passiflora L., providing an overview of all aspects related to the members of Passiflora subgenus Astrophea (DC.) Mast. It gives an account of their classification, morphology, distribution, habitats and ecology in order to provide a better understanding of the species included in this group. These examinations are factored into the recommendations forsuccessful ex situ cultivation which is generally regarded as difficult. More depth of information on cultivation is provided for the four species most commonly found under cultivation: Passiflora jussieui Feuillet, P. lindeniana Planch. ex Triana & Planch., P. macrophylla Spruce ex Mast. and P. pittieri Mast. Despite the problems these plants present in cultivation they are rewarding additios to any plant collection which in future is likely to be of great importance due to many being threatened in their natural habitats. This project is an extract from the author’s dissertation that was written for the Kew Diploma in Horticulture in 2012
The Temperate House Restoration Project
There is a long tradition at the Royal Botanic Gardens, Kew (RBG, Kew) of cultivating and displaying exotic plants from all over the globe, and the largest Victorian glasshouse, the Temperate House, traditionally showcases plants from temperate regions. The Temperate House Restoration Project was undertaken at RBG, Kew from 2012 to 2018. Over 1,000 species of plants were removed, propagated and replanted for this project, and this article describes the propagation of some of the most difficult to reproduce plant material. Four plant groups or species are presented: Erica verticillata P.J.Bergius, Quercus insignis M.Martens Galeotti, Pinus roxburghii Sargent and Banksia spp. L. This is in order to illustrate the variety of options available for propagating challenging species with attention to their ecology, biology and growing requirements.
Also provided are background information, reasons why these plants are considered difficult to multiply in cultivation, how plant material was sourced and the methods employed which led to successful propagation of the material at RBG, Kew. Propagation of the plants was heavily reliant on the horticultural expertise of those involved, and this expertise ensured that most of the original plant material was rejuvenated and new collections with scientific significance were added to the restored Temperate House
Morphological Trait Evolution in Solanum (Solanaceae): Evolutionary Lability of Key Taxonomic Characters
Solanum is one of the world\u27s largest and economically most important plant genera, including 1245 currently accepted species and several major and minor crops (e.g., tomato, potato, brinjal eggplant, scarlet eggplant, Gboma eggplant, lulo, and pepino). Here we provide an overview of the evolution of 25 key morphological traits for the major and minor clades of this giant genus based on stochastic mapping using a well-sampled recently published phylogeny of Solanum. The most evolutionarily labile traits (showing \u3e100 transitions across the genus) relate to plant structure (growth form and sympodial unit structure), herbivore defence (glandular trichomes), pollination (corolla shape and colour), and dispersal (fruit colour). Ten further traits show evolutionary lability with 50–100 transitions across the genus (e.g., specialised underground organs, trichome structure, leaf type, inflorescence position and branching, stamen heteromorphism). Our results reveal a number of highly convergent traits in Solanum, including tubers, rhizomes, simple leaves, yellow corollas, heteromorphic anthers, dioecy, and dry fruits, and some unexpected pathways of trait evolution that could be explored in future studies. We show that informally named clades of Solanum can be morphologically defined by trait combinations providing a tool for identification and enabling predictive phylogenetic placement of unsampled species
Phylogenomic discordance suggests polytomies along the backbone of the large genus Solanum
Premise Evolutionary studies require solid phylogenetic frameworks, but increased volumes of phylogenomic data have revealed incongruent topologies among gene trees in many organisms both between and within genomes. Some of these incongruences indicate polytomies that may remain impossible to resolve. Here we investigate the degree of gene-tree discordance in Solanum, one of the largest flowering plant genera that includes the cultivated potato, tomato, and eggplant, as well as 24 minor crop plants. Methods A densely sampled species-level phylogeny of Solanum is built using unpublished and publicly available Sanger sequences comprising 60% of all accepted species (742 spp.) and nine regions (ITS, waxy, and seven plastid markers). The robustness of this topology is tested by examining a full plastome dataset with 140 species and a nuclear target-capture dataset with 39 species of Solanum (Angiosperms353 probe set). Results While the taxonomic framework of Solanum remained stable, gene tree conflicts and discordance between phylogenetic trees generated from the target-capture and plastome datasets were observed. The latter correspond to regions with short internodal branches, and network analysis and polytomy tests suggest the backbone is composed of three polytomies found at different evolutionary depths. The strongest area of discordance, near the crown node of Solanum, could potentially represent a hard polytomy. Conclusions We argue that incomplete lineage sorting due to rapid diversification is the most likely cause for these polytomies, and that embracing the uncertainty that underlies them is crucial to understand the evolution of large and rapidly radiating lineages.Peer reviewe