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The pollen morphology of Adenandra Willd. (Rutaceae: Diosminae) was investigated to determine its taxonomic significance. Pollen of 27 of the 30 infrageneric taxa (representing 16 of the 18 species) was investigated by LM, SEM and TEM. Adenandra differs from all other Diosminae in having 4-colporate rather than 3-colporate pollen grains. This supports the alleged monophyletic status of the genus. Exine morphology and structure, however, is extremely diverse considering the size of the genus, with eight distinct pollen types and four subtypes being discerned. In some members the grains have uniform macroreticulate, striate or striato-reticulate sculpturing, whereas in others the poles have striate, striato-reticulate or reticulate-perforate sculpturing with various types of reticulate or rugulate sculpturing at the mesocolpia. Taxonomic groupings revealed by the pollen characters suggest elationships between taxa that were not previously apparent. It is suggested that evolutionary diversification among species of Adenandra is often more strikingly reflected by pollen morphology than by macromorphology, hence the eurypalynous state of the genus. [ABSTRACT FROM AUTHOR]

The pollen morphology of Diosma and Coleonema of the taxonomically problematic subtribe Diosminae (Rutaceae) was investigated to determine its taxonomic relevance. Pollen of 26 of the 28 species of Diosma and of each of the eight species of Coleonema was investigated by LM, SEM and TEM. In pollen of Diosma the exine sculpturing is uniform, and only one pollen type, reticulate, could be distinguished. In contrast, exine sculpturing shows interspecific variation in Coleonema and three distinct types, striate, reticulate and perforate, could be discerned. Species groupings indicated by the pollen types suggest possible relationships between species within Coleonema and with other genera that were not previously apparent. Pollen data support macromorphological evidence that suggests the generic re-classification of the Diosminae. [ABSTRACT FROM AUTHOR]

Describes the plant diversity conservation program in southern Africa. Importance of southern Africa's botanical diversity; Efforts by plant systematists to facilitate conservation of the region's botanical diversity; Activities of the Foundation for Research Development-sponsored plant systematics stimulation program; Promotion and marketing of plant systematics.

This note documents the events and conduct that led to the acceptance of Report 55 of the Permanent Committee for Spermatophyta concerning the conservation of Acacia Mill. with a new type. The procedures followed by the Nomenclature Section of the XVIIth International Botanical Congress (IBC) held in Vienna, Austria, in July 2005, are also outlined and briefly described in accordance with the provisions of the International Code of Botanical Nomenclature (ICBN) for dealing with committee reports. This controversial proposal to retypify Acacia Mill, from an African to an Australian type was accepted by the Committee for Spermatophyta, the General Committee, and the Nomenclature Section, a recommendation ratified by the final closing plenary session of the IBC. The ICBN emanating from the XVIIth IBC will include Acacia Mill., with a conserved type, in Appendix IIIA Nomina generica conservanda et rejicienda. For those who choose to follow the traditional classification system that applies the name Acacia in a broad sense to a heterogeneous assemblage of species comprising a number of subgenera, this decision holds no implications at generic level. However, should the alternative classification which segregates a broadly defined Acacia into a number of genera be followed, then the name Acacia would apply in a strict sense to the mainly Australian wattles (previously Acacia subg. Phyllodineae—now A. subg. Acacia—of the traditional system.) [ABSTRACT FROM AUTHOR]

The correct names and synonymy for species of Aloe sect. Chortolirion (A. Berger) Boatwr. & J.C. Manning (Asphodel-aceae:: Alooideae) are provided. This treatment recognises four species in this section, namely A. welwitschii, A. barendii, A.jeppeae and A. subspicata. Aloe subspicata and A. welwitschii are treated as conspecific by some authors. [ABSTRACT FROM AUTHOR]

The article offers information on the conservation proposal of name of Kumara which is a genus described by Medikus and named it as Kumara disticha. It discusses several facts related to conservation proposal which includes the protologue of Kumara is Aloe tipetala Medik that was considered as the synonymy of K.disticha, Aloe disticha was also included as a synonymy of Gasteria excavata and typification of the generic name.

In this article, the authors discuss a proposal to conserve the family name Asphodelaceae. The name Asphodelaceae which was published in the book Genera Plantarum in 1789, is used for family nomenclature. The name Hemerocallidaceae was established by botanist Robert Brown followed by Xanthorrhoeaceae. Asphodelaceae would remediate a situation where a well-established name is being displaced.

This article presents a proposal to conserve the genus Calvatia against an additional name, Lanopila. Calvatia is a type of genus of puffballs having outer casings whose upper parts break at maturity into angular pieces to expose the spores. The group constitutes more than 35 species, all characterized by fruit-bodies that burst by irregular fragmentation of the peridium and not by an apical pore.

Reports on the proposal to conserve Calvatia nom. cons. (Lycoperdaceae) against an additional name, Omalycus. Description and characterization of the Calvatia Fr.; Use of the generic name Calvatia in all mycological floras and guides worldwide, and the name Omalycus completely ignored.

Rangelands in South Africa, Lesotho, and Eswatini contain a rich diversity of valuable fodder trees and shrubs. This research is the first attempt to document the regional diversity and distribution of these browse resources. Scientific publications, textbooks, databases, and published reports were accessed to compile a database of plant species that were recorded as utilised by ruminants and non-ruminants. Relevant forage attributes, such as functional traits as well as utilisation traits, were added to each species record. Thereafter, distribution records were extracted from the South African National Biodiversity Institute's Botanical Database of South Africa and analysed with numerical techniques to establish phytogeographical patterns. A total of 613 plant species from 76 families have been recorded, which formed seven distinct phytochoria, termed the Central Arid, Eastern Subtropical, Highland Temperate, Moist Temperate, Northern Subtropical, Southern Temperate, and Western Arid browse-choria. Key families and species, as well as functional and utilisation traits, are discussed, focusing on key species present in the browse-choria. This browse database, together with the earlier compiled Leguminosae and Poaceae databases, will be used to prioritise indigenous southern African plant species/infraspecific taxa to be collected for the conservation of genetic resources and future evaluations for potential development as forage crops. [ABSTRACT FROM AUTHOR]

Mercury [Hg] emissions from old plant collections treated with mercuric chloride (HgCl2) may present a high health risk for staff working in certain herbaria. The present study evaluated Hg concentrations in ambient air, plant specimens and biological samples from staff working in the Pretoria National Herbarium (PRE) and the H.G.W.J. Schweickerdt Herbarium (PRU), University of Pretoria. Biological samples from a group of 15 people exposed to HgCl2 in herbaria and a non-exposed control group of five people were studied. Additionally, plant samples from herbarium specimens treated and non-treated with HgCl2 were analysed. Plant materials treated with HgCl2 had persistent high concentrations of Hg in the range of 114–432 µg g−1, whereas untreated materials were in the range of 0.20–0.45 µg g−1. The HgCl2-treated plant specimens induced elevated concentrations of Hg into the herbarium rooms near storage cabinets, where up to 1 μg m−3 of Hg was measured in the air of both herbaria. However, no significant difference in mean Hg concentrations in hair was found between herbarium workers and members of the control group, 0.46 and 0.64 µg g−1 respectively (p 0.05, Student''s t-test). For both groups, Hg concentrations were lower than that indicated by the World Health Organization [WHO] for non-exposed adults, namely 2 µg g−1. The mean concentration of total Hg in urine from the mercury-exposed herbarium group, 2.28 µg g−1 creatinine, was significantly higher than in the control group, 1.05 µg g−1 of creatinine. For both populations, the concentrations of Hg in their urine were below the threshold Hg values set by the WHO, i.e., 5 µg g−1 creatinine. We concluded that there was no strong response by individual herbarium staff from long-term exposure to Hg concentrations in the range of 0.28–1.1 μg m−3. [Copyright &y& Elsevier]

The article offers information on prototulbaghia (Alliaceae) from Sekhukhuneland, South Africa. Prototulbaghia siebertii is described as a small, slender, bulbous plant with fleshy leaves and crushed roots. Its flowers are white, often with a pink or purplish. The habitat of Prototulbaghia siebertii is unusual because it may be quite parched during the dry winter month but becomes permanently wet during the summer.

Abstract: The chemosystematic value of UV-absorbing leaf constituents was considered in previously uncharacterised representatives of Aloe section Pictae, the problematic maculate species complex. Comparative data indicate that the anthrone C-glycoside, 6′-malonylnataloin (7-hydroxychrysaloin 6′-O-malonate) is typical of maculate species in East Africa, but is unconvincing as a synapomorphy for section Pictae. A naphthalene derivative found widely in Aloe, plicataloside, was detected in Aloe greatheadii. Biogeographical trends were observed in the occurrence of the flavonoids isoorientin (luteolin-6-C-glucoside) and isovitexin (apigenin 6-C-glucoside). Isoorientin is a common constituent of tropical and sub-tropical species of Aloe, whereas isovitexin is restricted to a few southern African species. Isoorientin and isovitexin co-occur in the southern African maculate species Aloe parvibracteata, and the disjunct West African maculate species, Aloe macrocarpa. This is the first report of isoorientin and isovitexin in maculate species of Aloe; the presence of flavonoids in section Pictae is of taxonomic interest. [Copyright &y& Elsevier]

Premise of the Study: Herbarium specimens are increasingly used as records of plant flowering phenology. However, most herbarium-based studies on plant phenology focus on taxa from temperate regions. Here, we explore flowering phenologic responses to climate in the subtropical plant genus Protea (Proteaceae), an iconic group of plants that flower year-round and are endemic to subtropical Africa., Methods: We present a novel, circular sliding window approach to investigate phenological patterns developed for species with year-round flowering. We employ our method to evaluate the extent to which site-to-site and year-to-year variation in temperature and precipitation affect flowering dates using a database of 1727 herbarium records of 25 Protea species. We also explore phylogenetic conservatism in flowering phenology., Results: We show that herbarium data combined with our sliding window approach successfully captured independently reported flowering phenology patterns ( r = 0.93). Both warmer sites and warmer years were associated with earlier flowering of 3-5 days/°C, whereas precipitation variation had no significant effect on flowering phenology. Although species vary widely in phenological responsiveness, responses are phylogenetically conserved, with closely related species tending to shift flowering similarly with increasing temperature., Discussion: Our results point to climate-responsive phenology for this important plant genus and indicate that the subtropical, aseasonally flowering genus Protea has temperature-driven flowering responses that are remarkably similar to those of better-studied northern temperate plant species, suggesting a generality across biomes that has not been described elsewhere.

Ekebergia capensis is a medium-sized to large evergreen to deciduous tree ranging from southern Africa to Ethiopia. Two morphologically-distinct variants of E. capensis , southern and northern, may be recognized in southern Africa. Despite its wide distribution range there appear to be no published reports on the secretory structures occurring on the leaves. In very young leaves, colleters on the petiolules, adjacent portions of the rachis and the midrib of the adaxial leaflet surfaces, secrete fluid which at least partly covers these developing areas. This is the first record of colleters in Meliaceae. In addition, several extrafloral nectaries (EFNs) are found in variable positions on the abaxial side of the leaflets. No stomata are associated with the EFNs. The glandular tissue of active EFNs is surrounded by druse crystals of calcium oxalate and consists of secretory cells some of whose walls are separated by "strands" of amorphous lipophilic material, especially in a radial orientation. EFNs on developing leaves are inconspicuous but with time, frequently become more easily visible due to the accumulation of pinkish/reddish anthocyanins. Even on senescent leaves, shed in autumn, large droplets of nectar are frequently visible on the EFNs. The secretory tissue originates from protoderm and ground tissues. Slight differences in abundance, size, shape, position and structure exist between the EFNs of the southern and northern forms. Varying proportions of glucose, fructose and sucrose were detected in the rather viscous nectar with the most abundant sugar usually being fructose. Ants were only rarely observed feeding on the nectar. This finding is in conflict with the generally accepted idea that EFNs provide food for ants which in turn protect the plant from herbivores. More detailed studies of the chemistry of the nectar, which is relatively copious, may provide clues as to the function.