scholarly journals Opposing macroevolutionary and trait-mediated patterns of threat and naturalization in flowering plants

2020 ◽  
Author(s):  
J. P. Schmidt ◽  
T. J. Davies ◽  
M. J. Farrell
Keyword(s):  
Climate Variability ◽  
Generation Time ◽  
Native Species ◽  
Flowering Plants ◽  
The Other ◽  
Flowering Plant ◽  
Evolutionary Time ◽  
Short Generation Time ◽  
Plant Families ◽  
Time Autonomous

AbstractDue to expanding global trade and movement, new plant species are establishing in exotic ranges at increasing rates while the number of native species facing extinction from multiple threats grows. Yet, how species losses and gains globally may together be linked to traits and macroevolutionary processes is poorly understood. Here we show that, adjusting for diversification rate and age, the proportion of threatened species across flowering plant families is negatively related to the proportion of naturalized species. Moreover, naturalization is positively associated with climate variability, short generation time, autonomous seed production, and interspecific hybridization, but negatively with age and diversification; whereas threat is negatively associated with climate variability and hybridization, and positively with biotic pollination, age and diversification. Such a pronounced signature of naturalization and threat across plant families suggests that both trait syndromes have coexisted over deep evolutionary time and that neither strategy is necessarily superior to the other.

scholarly journals Flowering plant biodiversity of Augrabies Falls National Park: a comparison between Augrabies Falls National Park, Kalahari Gemsbok National Park, Vaalbos National Park and Goegap Nature Reserve

Koedoe ◽  
1999 ◽  
Vol 42 (2) ◽  
Author(s):  
P.C. Zietsman ◽  
H. Bezuidenhout
Keyword(s):  
Rare Species ◽  
National Park ◽  
Life Form ◽  
Nature Reserve ◽  
Flowering Plants ◽  
The Other ◽  
Flowering Plant ◽  
Plant Biodiversity ◽  
Conservation Areas ◽  
Number Of Species

A list of flowering plants has been compiled for the Augrabies Falls National Park, which occupies an area of approximately 18 600 ha. This list of 364 species represents 210 genera and 74 families. The Monocotyledonae are represented by 76 species (20.9 of the total number of species) and the Dicotyledonae by 288 (79.1 ). Approximately 54 of these species occur only in the Augrabies Falls National Park and not in one of the other conservation areas with which it was compared. According to the life form spectrum, the Augrabies Falls National Park is a therophyte-hemicryp- tophyte area. Five of these spesies are endemic to the Southern African floristic region. One of them is a rare species.

scholarly journals A genetic and molecular model for flower development in Arabidopsis thaliana

Development ◽  
1991 ◽  
Vol 113 (Supplement_1) ◽  
pp. 157-167 ◽  
Author(s):  
Elliot M. Meyerowitz ◽  
John L. Bowman ◽  
Laura L. Brockman ◽  
Gary N. Drews ◽  
Thomas Jack ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Flower Development ◽  
Molecular Model ◽  
Cell Types ◽  
Flowering Plants ◽  
Flowering Plant ◽  
Individual Plant ◽  
Know How ◽  
Preliminary Model ◽  
Plant Families

Cells in developing organisms do not only differentiate, they differentiate in defined patterns. A striking example is the differentiation of flowers, which in most plant families consist of four types of organs: sepals, petals, stamens and carpels, each composed of characteristic cell types. In the families of flowering plants in which these organs occur, they are patterned with the sepals in the outermost whorl or whorls of the flower, with the petals next closest to the center, the stamens even closer to the center, and the carpels central. In each species of flowering plant the disposition and number (or range of numbers) of these organs is also specified, and the floral ‘formula’ is repeated in each of the flowers on each individual plant of the species. We do not know how cells in developing plants determine their position, and in response to this determination differentiate to the cell types appropriate for that position. While there have been a number of speculative proposals for the mechanism of organ specification in flowers (Goethe, 1790; Goebel, 1900; Heslop-Harrison, 1964; Green, 1988), recent genetic evidence is inconsistent with all of them, at least in the forms in which they were originally presented (Bowman et al. 1989; Meyerowitz et al. 1989). We describe here a preliminary model, based on experiments with Arabidopsis thaliana. The model is by and large consistent with existing evidence, and has predicted the results of a number of genetic and molecular experiments that have been recently performed.

scholarly journals Limitation of current probe design for oligo-cross-FISH, exemplified by chromosome evolution studies in duckweeds

Chromosoma ◽  
2021 ◽  
Vol 130 (1) ◽  
pp. 15-25
Author(s):  
Phuong T. N. Hoang ◽  
Jean-Marie Rouillard ◽  
Jiří Macas ◽  
Ivona Kubalová ◽  
Veit Schubert ◽  
...  
Keyword(s):  
Growth Rate ◽  
Chromosome Number ◽  
Chromosome Evolution ◽  
Sequence Similarity ◽  
Flowering Plants ◽  
The Other ◽  
Probe Design ◽  
Congeneric Species ◽  
Specific Design ◽  
Spirodela Polyrhiza

AbstractDuckweeds represent a small, free-floating aquatic family (Lemnaceae) of the monocot order Alismatales with the fastest growth rate among flowering plants. They comprise five genera (Spirodela, Landoltia, Lemna, Wolffiella, and Wolffia) varying in genome size and chromosome number. Spirodela polyrhiza had the first sequenced duckweed genome. Cytogenetic maps are available for both species of the genus Spirodela (S. polyrhiza and S. intermedia). However, elucidation of chromosome homeology and evolutionary chromosome rearrangements by cross-FISH using Spirodela BAC probes to species of other duckweed genera has not been successful so far. We investigated the potential of chromosome-specific oligo-FISH probes to address these topics. We designed oligo-FISH probes specific for one S. intermedia and one S. polyrhiza chromosome (Fig. 1a). Our results show that these oligo-probes cross-hybridize with the homeologous regions of the other congeneric species, but are not suitable to uncover chromosomal homeology across duckweeds genera. This is most likely due to too low sequence similarity between the investigated genera and/or too low probe density on the target genomes. Finally, we suggest genus-specific design of oligo-probes to elucidate chromosome evolution across duckweed genera.

scholarly journals Flowering plant embryos: How did we end up here?

2021 ◽  
Author(s):  
Stefan A. Rensing ◽  
Dolf Weijers
Keyword(s):  
Current Knowledge ◽  
General Structure ◽  
Three Dimensional ◽  
Flowering Plants ◽  
Flowering Plant ◽  
Adult Plant ◽  
Ancestral State ◽  
Evolutionary Trajectory ◽  
Current State ◽  
Plant Embryo

AbstractThe seeds of flowering plants are sexually produced propagules that ensure dispersal and resilience of the next generation. Seeds harbor embryos, three dimensional structures that are often miniatures of the adult plant in terms of general structure and primordial organs. In addition, embryos contain the meristems that give rise to post-embryonically generated structures. However common, flowering plant embryos are an evolutionary derived state. Flowering plants are part of a much larger group of embryo-bearing plants, aptly termed Embryophyta. A key question is what evolutionary trajectory led to the emergence of flowering plant embryos. In this opinion, we deconstruct the flowering plant embryo and describe the current state of knowledge of embryos in other plant lineages. While we are far yet from understanding the ancestral state of plant embryogenesis, we argue what current knowledge may suggest and how the knowledge gaps may be closed.

Flowering Plant Families of East Africa. An Introduction to Plant Taxonomy

Kew Bulletin ◽  
1995 ◽  
Vol 50 (3) ◽  
pp. 668
Author(s):  
J. M. Lock ◽  
John O. Kokwaro
Keyword(s):  
East Africa ◽  
Flowering Plant ◽  
Plant Taxonomy ◽  
Plant Families

Chemical principles of Boophone, Nerine, Crossyne, Clivia, Cryptostephanus, Haemanthus and Scadoxus of the South African Amaryllidaceae and their biological properties

Planta Medica ◽  
2021 ◽  
Author(s):  
Jerald Nair ◽  
Johannes Van Staden
Keyword(s):  
South African ◽  
Biological Activities ◽  
Structural Diversity ◽  
Biological Properties ◽  
Isoquinoline Alkaloid ◽  
Flowering Plant ◽  
New Information ◽  
Regulatory Effects ◽  
Plant Families ◽  
Antioxidant Effects

The Amaryllidaceae features prominently amongst bulbous flowering plant families. Accommodating about a third of its species, South Africa affords a sound basis for Amaryllidaceae plant research. Boophone, Nerine, Crossyne, Clivia, Cryptostephanus, Haemanthus and Scadoxus have been well-represented in such endeavors. The account herein summarizes the studies undertaken between 2013-2020 on these genera in regards to their chemical and biological characteristics. A total of 136 compounds comprising 63 alkaloids and 73 non-alkaloid entities were described during this period from eighteen members of the title genera. The alkaloids were reflective of the structural diversity found in eight isoquinoline alkaloid groups of the Amaryllidaceae. Of these, the crinane (29 compounds), lycorane and homolycorine (11 compounds each) groups were the most-represented. The non-alkaloid substances were embracive of the same number of unrelated groups including, acids, phenolics, flavonoids and triterpenoids. A wide variety of assays were engaged to ascertain the biological activities of the isolated compounds, notably in regards to cancer and motorneuron-related diseases. There were also attempts made to determine the antimicrobial, anti-inflammatory and antioxidant effects of some of the substances. New information has also emerged on the herbicidal, insecticidal and plant growth regulatory effects of selected alkaloid principles. Coupled to the biological screening measures were in instances probes made to establish the molecular basis to some of the activities, particularly in relation to cancer and Parkinsonʹs disease.

scholarly journals Floral Resources Sustaining African Meliponine Bee Species (Hymenoptera: Meliponini) in a Fragile Habitat of Kenya

2016 ◽  
Vol 8 (1) ◽  
pp. 42 ◽  
Author(s):  
Bridget O. Bobadoye ◽  
Paul N. Ndegwa ◽  
Lucy Irungu ◽  
Fombong Ayuka ◽  
Robert Kajobe
Keyword(s):  
Flowering Phenology ◽  
Abundant Species ◽  
Flowering Plants ◽  
Flowering Plant ◽  
Floral Resources ◽  
Habitat Gradients ◽  
Naturally Occurring ◽  
Taita Hills ◽  
Insect Pollinators ◽  
Diverse Habitat

A vast majority of insects visit flowers for food, generally termed as floral rewards. Detailed insights on flowering phenology of plants could give a hint of habitat status and the extent to which such landscapes could support insect pollinators to render both direct and indirect ecosystem services. This study monitored flowering plants which could potentially provide both pollen and nectar sources to four African meliponine bee species (Apidae: Meliponini) naturally occurring in six diverse habitat gradients of the eastern arc mountains (Taita hills) of Kenya. Blooming sequences of identified flowering plants overlapped across seasons with approximately 80 different plant species belonging to 34 families recorded, with the highest proportions from Fabaceae and Asteraceae families dominating flowering plants that were visited (67% of the visits).  A flowering calendar is presented to indicate the phenological pattern of all identified floral resources.  Hypotrigona gribodoi being the most abundant species had the highest visitation rates on plants belonging to Fabaceae and Asteraceae families, followed by Meliponula ferruginea (black), Plebeina hildebrandti and Hypotrigona ruspolii. This indicates that such fragile habitat could invariably sustain nutritional requirements essential for the survival of insect pollinators such as native meliponine bee species, though bee abundance at flowers did not significantly correlate to food availability (expressed by flowering plant richness).

scholarly journals Recording plant status and regeneration during single visits

2019 ◽  
Vol 1 (4) ◽  
pp. 283-291
Author(s):  
Kevin J. Walker ◽  
Simon Leach ◽  
Chris Preston ◽  
Thomas Humphrey ◽  
Trevor James ◽  
...  
Keyword(s):  
Plant Species ◽  
Native Species ◽  
Objective Measure ◽  
The Other ◽  
A Site

Information on the origin (status) and regeneration of plant species improves our understanding of native distributions and the establishment of non-native species. However, current categories used to record status in Britain and Ireland, whilst conceptually informative, rely on a knowledge of persistence that is impossible to assess objectively during a single (one-off) recording visit. We propose five alternative categories that focus on origin (how a species arrived at a site) rather than persistence. The first two categories apply to nationally native taxa: (1) populations that are unequivocally native and (2) those that are likely to have been introduced and/or are spreading for reasons that are obscure. The other three categories cover the occurrences of any taxon, native or non-native, that is known or suspected to have been introduced to a site: (3) introductions with unknown/obscure origins; (4) deliberate introductions; and (5) accidental introductions. For the introduced categories 3-5 we recommend that botanists also record signs of regeneration, i.e. seedlings or widely scattered patches, as a more objective measure whether a species is likely to be self-sustaining in a given locality.

scholarly journals The World Flora Online 2020 project: will Cameroon come up to the expectation?

Rodriguésia ◽  
2015 ◽  
Vol 66 (4) ◽  
pp. 961-972 ◽  
Author(s):  
Jean Michel Onana
Keyword(s):  
Plant Species ◽  
Flowering Plants ◽  
West African ◽  
Tropical Africa ◽  
African Countries ◽  
Red Data Book ◽  
The World ◽  
Data Book ◽  
Plant Families ◽  
High Level

Abstract Biodiverse Cameroon has been highlighted as the top country in tropical Africa for plant species diversity per degree square, with a higher diversity than all other West African countries added together, and including two of the top documented centres of plant diversity in Tropical Africa. Despite its reduced taxonomic capacity, with only six active taxonomists a high level of botanical activity in the country has resulted in accomplishments such as the databasing of the YA Herbarium (over 60,000 records), which has an in-country collection coverage of almost 95% of the known plant species that are recorded for Cameroon. Other accomplishments are the Red Data Book of the Flowering Plants of Cameroon, several local checklists and published volumes of the Flore du Cameroun which covers 37% of the country's species. Currently the checklist of Cameroon records 7,850 taxa at species and infraspecific level. Resources are needed to support and heighten the profile of this small botanical community. Already thanks to strong collaboration between Cameroon and renowned botanical institutes of others countries, in particular France and United Kingdom, one hundred and thirteen plant families have been published and would help this country to complete the recording of its biodiversity towards contributing to the World Flora Online 2020 project.

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