Taxonomic studies of the genus Hypoxis in East Africa

East African material of the genus Hypoxis L. has preliminarily been divided into the heterogenous, probably apomictic H. obtusa Burch- complex (2n = 40–50, ca. 75, 76, ca. 85, >86, ca. 92, ca. 98, ca. 108, 130–135, 160–200) and 5 rather homogenous species: H. angustifolia Lam. (2n = 14, 28), H. goetzei Harms (2n = ca. 62), H. kilimanjarica Bak., H. malosana Bak. (2n = 14) and H. macrocarpa Holt & Staubo sp. nov. H. kilimanjarica is divided into ssp. kilimanjarica and ssp. prostrata Holt & Staubo ssp. nov.     

Characteristics of some lactic Acid bacteria used as starter cultures in dry sausage production

The fermentation characteristics of two commercial (Duploferment 66 and Saga II) and five Norwegian lactic acid bacteria used in dry sausage production were compared with those of Lactobacillus plantarum ATCC 8014. The Norwegian strains lacked the ability to ferment mannitol, sorbitol, lactose, and d-(+)-raffinose and grew at 8 but not at 42 degrees C, in contrast to the ATCC culture and the two commercial strains. The lactate dehydrogenase activity of the Norwegian strains was not stimulated by pyruvate. All strains were capable of peroxide destruction when grown in the presence of myoglobin.     

Viola suavis, a new species in the Nordic flora, with analyses of the relation to other species in the subsection Viola (Violaceae)

Evidence from cytology, enzyme markers and morphometry suggest that a species of Viola (Violaceae) collected in southeastern Norway should be referred to V. suavis , although differing in some phenotypic traits. V. suavis is not previously known from the Nordic countries, but must now be regarded as an established member of the Norwegian flora. It was probably introduced more than a century ago, providing an interesting analogy to the situation of V. alba in Öland (Sweden). Thus, it seems like human activity have played a role for expanding the distribution areas of several of the species within Viola subsection Viola (V. alba, V. hirta, V. odorata and V. suavis ). Electrophoretic evidence showed that the basal chromosome number of the subsection is x=5. V. suavis (2n=40) is allo-octoploid, and closely related tetraploid taxa were easily recognized. However, it is difficult to trace its origin to lower-ploid ancestors, and it seems likely that the complex may have contained extinct taxa with other allelic combinations that better explain the origin of V. suavis .     

The uses of Kenyan aloes: an analysis of implications for names,distribution and conservation

Background

The genus Aloe is renowned for its medicinal and cosmetic properties and long history of use. Sixty-three Aloe species occur in Kenya, of which around 50 % are endemic. Several species of aloes are threatened with extinction and knowledge about their use is of major importance for sound conservation strategies. The main aims of this study were to assess the biocultural value of Aloe in Kenya by documenting local uses of aloes and evaluating how the vernacular names reflect the relative importance in different ethnic groups.

Methods

Ethnobotanical and ethnotaxonomical data were collected using field observations and semi-structured interviews. Information was collected by interviewing 63 respondents from nine different ethnic groups, representing different ages, gender and occupations. Statistical analyses were performed using R version 3.1.2.

Results

A total of 19 species of Aloe were found in the study area, of which 16 were used. On the generic level Aloe was easily distinguished. At species level, the local and scientific delimitation were almost identical for frequently used taxa. Aloe secundiflora, with 57 unique use records was the most important species. The two most frequently mentioned Aloe treatments, were malaria and poultry diseases. In our study area neither age nor gender had a significant influence on the level of knowledge of Aloe use. Finally, no correlation was found between extent of use and people’s perception of decrease in local aloe populations. The aloes are highly appreciated and are therefore propagated and transported over large areas when people relocate.

Conclusion

Biocultural value is reflected in the ethnotaxonomy of Aloe in Kenya. Different ethnic groups recognise their most-valued Aloe at the genus level as “the aloe” and add explanatory names for the other species, such as the “spotted aloe” and the “one-legged aloe”. Widespread species of Aloe have the highest number of uses. There is no obvious correlation with high use and decrease in abundance of aloes locally, and we found no compelling evidence for local uses causing devastating damage to populations of the 19 species in use, whereas habitat loss and commercial harvesting appear to be of urgent concern for these important plants.

     

Microsatellite markers show decreasing diversity but unchanged level of clonality in Dryas octopetala (Rosaceae) with increasing latitude

? Premise of the study: Average arctic temperatures have increased at almost twice the global average in the past 100 years. Most studies on biodiversity along latitudinal gradients have focused on species richness or genetic diversity at lower latitudes, and only a few studies have inferred genetic diversity within a species along a latitudinal gradient at higher latitudes, even though these areas might be most affected by recent climate changes. Here, intraspecific genetic diversity of the arctic-alpine Dryas octopetala (Rosaceae) is studied along a latitudinal gradient to test the hypotheses that genetic diversity decreases and vegetative clonal growth increases with latitude. ? Methods: Ten microsatellite markers have been developed for D. octopetala and analyzed with population genetic methods in five populations along a latitudinal transect spanning from 59.0°N to 79.9°N. ? Key results: The nine microsatellites that were used in the final analyses resulted in a resolution high enough to distinguish between ramets while providing useful information at a larger geographical scale. Three genetic clusters were indicated, a southern Norway group, a northern Norway group, and a Svalbard group, with corresponding decreasing genetic diversity. No trend was found with regard to clonality along the gradient. ? Conclusions: The newly developed microsatellite markers provide a useful tool for further genetic studies of D. octopetala and its close relatives, addressing population structure as well as phylogeographic patterns. The results of this study support the hypothesis of decreasing genetic diversity with increasing latitude, which may have implications for future adaptability to climate change.     

Traditional Ecological Knowledge of a Riverine Forest in Turkana, Kenya: Implications for Research and Management

The present study explores traditional ecological knowledge (TEK) of Turkana pastoralists and cultivators in the context of a riverine forest in northern Kenya. The Turkwel River and its floodplain sustain a thick forest, which is used for grazing and extraction of non-timber forest products. However, sedentarisation and agricultural expansion have resulted in localised clear-felling of trees, while river damming has altered the natural flow regime. A series of structured, semi-structured, and group interviews were combined with a botanical inventory in order to assess the relevance of TEK to ecological research and forest conservation. Turkana informants gave 102 vernacular names for the 113 woody species. Of these, 85% had a domestic or pastoral use among the 105 specific uses that were described. Ethnobotanical knowledge was relatively homogenous and not related to age, gender, or source of livelihood. The informants had in-depth knowledge of some key ecological processes. The conceived threats to forest survival were primarily cultivation and permanent settlements, while the effects of river damming and livestock grazing were disputed. A claimed decline in rainfall was confirmed by official data. There is strong evidence that TEK could be used to generate hypotheses for research and to design sustainable conservation strategies. A revised version of the indigenous system of tree management should be incorporated into the official forestry policy in order to resolve future conflicts between pastoralists and cultivators.     

Viola rupestris: molecular analyses to elucidate postglacial migration in Western Europe

Aim Our aim was to elucidate the postglacial migration of Viola rupestris F.W. Schmidt, with its two subspecies, rupestris and relicta Jalas, in Europe, using molecular methods. Location Norway, Sweden, Finland, England, the Netherlands, France and Switzerland. Methods Isoenzymes were analysed from 49 populations of Viola rupestris s.lat. Based on former experience of variation in the taxon, the following were included: aspartate aminotransferase, leucine/aminopeptidase, and phosphoglucomutase, yielding a total of nine interpretable and six variable (putative) loci. Results Six multilocus phenotypes were revealed (A–F). Phenotype A (only one individual) is restricted to northern Norway, B is shared by all populations in northern Norway and an isolated population on the west coast of southern Norway (Møre). Phenotype B comes close to C, co‐occurring with D in England, the latter also occurring in southern France. Phenotypes E and F occur in the rest of Europe. Main conclusions Viola rupestris ssp. relicta Jalas, previously known only from northern Scandinavia (northern unicentric), was discovered on the west coast of southern Norway (Møre), making the taxon ‘bicentric’. Populations are connected through a putative migration route from the Grands Causses in southern France (Massif Central) via England and western Norway to northern Scandinavia. The Grands Causses might represent a glacial refugium.     

Ecotypic differentiation in relation to soil nitrogen in northern Scandinavian Cochlearia officinalis

Ecotypic differentiation of Cochlearia officinalis L. was studied in four populations, roughly described as "beach", "bird cliff", "spring" and "estuary", which occupy different habitats in the northern part of Norway. The plants were cultivated under controlled conditions on soil to which nitrogen was applied at various amounts (0, 0.2 and 1.0 g N pot⁻¹). The above ground part of the "bird cliff" population showed the highest dry weight and nitrogen uptake at the highest nitrogen concentration. No effect of nitrogen treatment and the lowest dry weight were found in the "estuary" population. The differences in population response to added nitrogen were correlated to the nitrogen content of the soil in their natural habitat. Morphological features of the populations were also significantly different. The "estuary", "beach" and "bird cliff" populations showed differences in all characteristics measured – ratio of length/width of the leaves, shape of the leaf base, and length of the petiole. "Beach" and "spring" differed significantly in petiole length, while "bird cliff" and "spring" differed significantly in both leaf ratio and shape of the leaf base. These morphological features were not significantly altered by the application of nitrogen to the soil. This study shows that the four populations of Cochlearia officinalis are discrete biotypes characteristic of distinct habitats, and therefore, should be considered ecotypes.