Mwafongo E.,National Herbarium |
Nordal I.,University of Oslo |
Magombo Z.,National Herbarium |
Stedje B.,University of Oslo
Ethnobotany Research and Applications | Year: 2010
This paper reports on the findings of an ethnobotanical survey of geophytes used in 15 selected districts of Malawi. The survey was initially driven by the need to assess the conservation status and use of Lilioid monocots of the family Hyacinthaceae. Altogether, 49 geophytes were documented as useful for food (24%), medicine (58%) and other purposes (18%). The most commonly reported species was Dioscorea odoratissima Pax. (Dioscoreaceae). Monocots represented 45% of the total. Members of the family Hyacinthaceae were only represented by 3 (6%) species Albuca abyssinica Jacq., Ledebouria cordifolia (Baker) Stedje & Thulin and Ledebouria revoluta (L.f.) Jessop. The study has further explored six alternative methods of evaluating sampling effort and estimating species richness. Michaelis-Menten Means estimator appeared to be the best estimator of species richness but was not able to accurately predict species richness for all the data combined. A bootstrap estimator was found to be more accurate. It was also apparent from the survey of geophytes that species in the Asteraceae and Fabaceae are more sought after for food and medicine than hyacinthoide monocots evidenced by fewer representatives mentioned by respondents.
Jayasuriya K.M.G.G.,University of Peradeniya |
Baskin J.M.,University of Kentucky |
Baskin C.C.,University of Kentucky |
Fernando M.T.R.,National Herbarium
Research Journal of Seed Science | Year: 2012
Non dormancy, three of the five classes of dormancy and orthodox and recalcitrant storage behavior occur in seeds of Fabaceae. The aim of the study was to characterize whole-seed dormancy and storage behavior in seeds of three tropical species of Derris (Fabaceae), which are lianas. Seed Moisture Content (MC); effects of drying and low temperature on viability; water-uptake of intact and scarified seeds; and effects of scarification, fruit coat removal and GAS on germination were determined. Seed coat anatomy was studied to check for evidence of physical dormancy. Seeds of D. parvifolia and D. scandens had low MC and those of D. trifoliata high MC. D. trifoliata seeds were sensitive to both drying and low temperature storage. Seeds of D, scandens were water-impermeable and those of D. parvifolia and D. trifoliata water-permeable. D. parvifolia seeds germinated without treatment, whereas those of D. scandens required scarification. Removal of fruit coat and application of GAS overcame dormancy in D. trifoliata seeds. A palisade layer was present only in the seed coat of D. scandens. D, trifoliata seeds are recalcitrant and those of the other two species orthodox. Seeds of D. parvifolia are nondormant and those of D. scandens and D, trifoliata have Physical (PY) and Physiological (PD) dormancy, respectively. The ecological implications of nondormancy/dormancy in relation to orthodoxy/recalcitrant seed storage behavior in tropical lianas are discussed. © 2012 Academic Journals Inc.
Visser V.,University of South Africa |
Fish L.,National Herbarium |
Cook G.D.,CSIRO |
Richardson D.M.,Center for Invasion Biology
Global Ecology and Biogeography | Year: 2016
Aim: Some regions donate more invaders from particular taxonomic and functional groups than they receive. We demonstrate a particularly striking donor-recipient asymmetry in invasion ecology in grasses. Specifically, we explore whether low numbers of invasive grasses in South Africa can be explained by sampling biases, introduction dynamics, species traits or invasibility of ecosystems. Location: South Africa, Australia, Chile, Europe and the USA. Methods: We tested for a donor-recipient asymmetry using lists of native and non-native grasses in five regions across the globe. Then, using distribution, trait and environmental data, we tested whether regions differed in: (1) herbarium sampling effort; (2) introduction dynamics of non-native grasses (primary uses, area of origin and minimum residence time of non-native grasses); (3) traits of native and non-native grasses (leaf size, height, life history, growth form, C3:C4 ratio and taxonomic placement); and (4) fire frequency. Results: South Africa has fewer invasive grasses, and fewer widespread invasive grasses, than other regions; while grasses native to South Africa are much more likely to be invasive elsewhere than other grasses. This asymmetry cannot be explained by sampling biases, historical trade links or minimum residence time. Rather it is likely to be due to a combination of: (1) the massive scale of the introduction of South African grasses around the world; (2) specific traits that make South African grasses successful competitors; and (3) the high fire frequency of many South African ecosystems to which many native grasses are adapted, but introduced grasses are not. Main conclusion: South Africa has a high diversity of grasses that possess specific traits to cope with fire, grazing and disturbance. This makes them more competitive. Moreover, the high diversity of certain grass lineages in South Africa acts as a reservoir of potential invaders and possibly helps limit invasions in South Africa by promoting fire. © 2016 John Wiley & Sons Ltd
Henriette E.,University of Seychelles |
Larridon I.,Ghent University |
Morel C.,National Herbarium |
Goetghebeur P.,Ghent University |
And 2 more authors.
Phytotaxa | Year: 2015
Knowledge of the monocot flora of the Seychelles remains relatively weak and new taxonomic studies, including both herbarium specimens and field observations, are needed. Extensive new explorations in the key biodiversity areas of the Seychelles granitic islands resulted in the discovery of an unknown species of Costularia. After careful examination of existing specimens and literature within that genus, we concluded that the unknown plant corresponds to the type of Cladium xipholepis, a species endemic to the Seychelles which had previously been confused and put into synonymy with two unrelated taxa, i.e. the other Seychelles endemic Costularia hornei and the Mascarene species C. melicoides. These confusions were due to the immature state of the type of Cladium xipholepis, which was the only known specimen of the species. The name Cladium xipholepis is here resurrected and combined in the genus Costularia, adding one endemic species to the flora of the Seychelles. In addition, a detailed description is provided, correcting important errors regarding diagnostic characters made in the original description. Costularia xipholepis is a rare species, occurring on lower montane inselbergs of Mahé Island, and is here proposed as endangered (EN) according to IUCN Red List categories and criteria. It is morphologically closely related to C. pantopoda var. baronii from Madagascar. The other Seychelles endemic Costularia, C. hornei (lectotype designated here), has no close relative and belongs to a group distributed in South-East Asia. We discuss these results in relation to the origins of the flora of the Seychelles. Finally, the previously thought endemic variety Costularia hornei var. rectirhachilloidea was also reviewed and we consider it to be identical to the type variety, but based on specimens at an earlier stage of spikelet development. These discoveries, along with other preliminary studies, indicate that more studies are needed to review the monocots of the Seychelles, particularly Cyperaceae, Orchidaceae and Poaceae. © 2015 Magnolia Press.
Cabrera J.,University Mainz |
Jacobs S.W.L.,National Herbarium |
Kadereit G.,University Mainz
Telopea | Year: 2010
Camphorosmeae (Chenopodiaceae, formerly Sderolaeneae) are widespread across all states of Australia. Molecular data revealed that the Australian Camphorosmeae represent a monophyletic lineage comprising 147 currently recognised species, 145 of which are endemic to Australia. Like their Eurasian relatives most Australian Camphorosmeae are well-adapted to dry and saline environments, and most species are distributed in semi-arid or arid landscapes of the Eremaean area of central and western Australia. The historical biogeography of the Australian Camphorosmeae is analysed using an ETS phylogeny of the group and DIVA. We found that diversification of the tribe started at the end of the Miocene, and that radiation took place during the Pliocene, probably driven by the aridification of Australia during this time. Southern west Australia probably served as the ancestral area, and we hypothesise that the ancestors of Australian Camphorosmeae were already adapted to dry and saline conditions and might have been distributed in coastal or saline inland habitats. Successful dispersal and establishment of Camphorosmeae in the then newly developed arid regions was probably enhanced by niche pre-emption. Our timing of the radiation of this drought-adapted lineage and the directions of its dispersal support the hypothesis that the aridification of Australia started during the Late Miocene and arid areas expanded during the Pliocene from the west to the east and then north. © 2011 Royal Botanic Gardens and Domain Trust.
Williams V.L.,University of Witwatersrand |
Victor J.E.,National Herbarium |
Crouch N.R.,Ethnobotany Unit |
Crouch N.R.,University of KwaZulu - Natal
South African Journal of Botany | Year: 2013
In 2009, South Africa completed the IUCN Red List assessments of 20,456 indigenous vascular plant taxa. During that process, medicinal plant species (especially those sold in informal muthi markets) were identified so that potential extinction risks posed to these species could be assessed. The present study examines and analyses the recently documented threat statuses of South African ethnomedicinal taxa, including the number of species used, revealing family richness and the degree of endemism, and calculates the Red List Index (RLI) of species survival to measure the relative degree of threat to medicinal species. Approximately 2062 indigenous plant species (10% of the total flora) have been recorded as being used for traditional medicine in South Africa, of which it has been determined that 82 species (0.4% of the total national flora) are threatened with extinction at a national level in the short and medium terms and a further 100 species are of conservation concern (including two species already extinct in the wild). Thirty-two percent of the taxa have been recorded in traditional medicine markets in the provinces of KwaZulu-Natal, Gauteng, Eastern Cape, Mpumalanga and Limpopo. The study also reflects on the challenges associated with Red List evaluations of medicinal species, many of which, based on market reports, are extracted at a seemingly unsustainable rate. In contrast to the majority of species enumerated in the Red List of South African plants, medicinal taxa are often widespread, with large extents of occurrence. Accordingly, the population decline criteria have necessarily been applied to assess threats to their existence, even though accurate figures for numbers of remaining individuals, areas of occupancy, quantities harvested, and regeneration times are often found lacking. Factors leading to susceptibility of plant species to extinction as a result of harvesting pressure are discussed. The current findings reveal a need for greater emphasis on focussed population level research on prioritised medicinal plant species. © 2013 South African Association of Botanists.
Jacobs S.W.L.,National Herbarium |
Hellquist C.B.,Massachusetts College of Liberal Arts
Telopea | Year: 2010
Nymphaea Iukei and N. noelae, both Nymphaeaceae subgenus Confluentes, are described from the Kimberley region of Western Australia and Cape York region of Queensland respectively. The new combination and status of Nymphaea kimberleyensis is provided for Nymphaea immutabilis subsp. kimberleyensis from Western Australia. From Central Eastern Queensland Nymphaea jacobsii (subgenus Anecphya), with two subspecies, and N. vaporalis are described as new taxa. The potential hybrid origin of N. kimberleyensis and N. vaporalis is discussed, as is the presence of an intergrade complex. Another hybrid, N. jacobsii x N. violácea, is described but not named. A key is provided for the native and naturalised species of Nymphaea in Australia. © 2011 Royal Botanic Gardens and Domain Trust.
Dunk C.W.,La Trobe University |
Lebel T.,National Herbarium |
Keane P.J.,La Trobe University
Mycorrhiza | Year: 2012
The occurrence of the exotic ectomycorrhizal fungus Amanita muscaria in a mixed Nothofagus-Eucalyptus native forest was investigated to determine if A. muscaria has switched hosts to form a successful association with a native tree species in a natural environment. A mycorrhizal morphotype consistently found beneath A. muscaria sporocarps was examined, and a range of morphological and anatomical characteristics in common with those described for ectomycorrhizae formed by A. muscaria on a broad range of hosts were observed. A full description is provided. The likely plant associate was determined to be Nothofagus cunninghamii based upon anatomy of the roots. Analysis of ITS-1 and ITS-2 regions of nuclear ribosomal DNA sequences confirmed the identities of both fungal and plant associates. These findings represent conclusive evidence of the invasion of a non-indigenous ectomycorrhizal fungus into native forest and highlight the ecological implications of this discovery. © 2011 Springer-Verlag.
Barkworth M.E.,Utah State University |
Jacobs S.W.L.,National Herbarium
Telopea | Year: 2010
We endorse recognition of four morphologically and cytologically distinct genera for Australasia's native Triticeae: Australopyrum, Stenostachys, Anthosachne and Connorochloa. To encourage adoption of this recommendation, we present a key to all genera of Triticeae found in Australasia, descriptions of the native genera, keys to their species, the new combinations required to implement our generic recommendations (Anthosachne falcis, A. fertilis, A. longiseta, A. multiflora var. kingiana, A. plurinervis, A. rectiseta, A. solandri and Stenostachys enysii), and representative line drawings. These and additional identification resources are available on the web at http://herbarium.usu.edu/triticeae. We also lectotypify Agropyron velutinum Nees. © 2011 Royal Botanic Gardens and Domain Trust.
Tikssa M.,Addis Ababa Institute of Technology |
Bekele T.,Addis Ababa Institute of Technology |
Kelbessa E.,National Herbarium
African Journal of Ecology | Year: 2010
The vegetation along the Awash River (1200-km long) in the main Ethiopian Rift, and its relationship with environmental factors was studied. Seven plant communities were described from the study area: (1) Acacia nilotica subsp. leiocarpa. - Carissa edulis type; (2) Acacia robusta subsp. usambarensis - Acokanthera schimperi type; (3) Celtis africana - Mimusops laurifolia type; (4) Acacia senegal - Acacia mellifera - Dobera glabra type; (5) Acacia nilotica subsp. indica - Ficus capreaefolia type; (6) Lannea schimperi- Glycine wightii type; and (7) Tamarix nilotica - Acacia hocki community type. It has been shown that the plant communities along the river follow an altitudinal gradient. The vegetation of the Awash River is mainly the result of the interactions between edaphic factors, the hydrology, altitude, slope and climate. © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd.