Seed Germination Enhancement of Two Balanites Species (B. aegyptiaca (L.) Del. and B. rotundifolia (Tiegh.) Blatt.) Using Different Presowing Treatments in Ethiopia.

B. aegyptiaca and B. rotundifolia are known to be multipurpose trees with various uses and values. Therefore, the aim of this study was to investigate the seed germination behaviours of B. aegyptiaca and B. rotundifolia under different presowing treatments. Hence, seeds were collected from the Central and Southern Ethiopian Rift Valley regions. Then, a total of 864 fruits (seeds) subjected to eight different presowing treatments and planted in pots arranged in a completely randomized design (CRD) were tested for each species. The mean germination percentage (GP), mean daily germination percentage (GD), mean germination time (GT), and mean germination index (GI) were computed. One-way ANOVA showed the presence of significant GP, GD, GT, and GI among treatment groups at p < 0.05 under both Balanites species. For B. aegyptiaca, Tukey's HSD test showed that seeds soaked with 98% H2SO4 for 10 minutes (98HSO10m) and 20 minutes (98HSO20m) have the highest GPs (87 ± 8.8 and 82 ± 10.2, respectively) that are significant at p < 0.05. The seeds soaked in 75°C hot water for 10 minutes and subsequently cooled for 12 hours (HW75d), 98HSO10m, and 98HSO20m have the highest GDs (2%) that are significant at p < 0.05. Moreover, 98HSO20m, 98HSO10m, and seeds soaked in cold water for 48 hours at room temperature of 25°C (CW48h) have the shortest GTs (24 ± 2.2, 25 ± 0.5, and 25 ± 1.3, respectively), and 98HSO10m and 98HSO20m have the highest GIs (1.04 ± 0.09 and 1.01 ± 0.08, respectively) that are significant at p < 0.05. For B. rotundifolia, the control recorded the highest cumulative germination (i.e., 71), followed by CW48h (i.e., 51). However, Tukey's HSD tests generally indicated that no treatment group resulted in significant differences in the means of GP, GD, GT, and GI at p < 0.05. So, no treatment group was observed to enhance the germination of B. rotundifolia compared to the control. However, this study generally indicated potential seed enhancement technologies for B. aegyptiaca with greater implications for propagation, conservation, and sustainable utilization of the species in the agricultural and pastoral communities of Ethiopia.

Herbal medicine used by the community of Koneba district in Afar Regional State, Northeastern Ethiopia.

BACKGROUND: Pastoral communities of the Afar people in northeastern Ethiopia use medicinal plants for various health problems. However, very limited scientific documents are found addressing ethnomedicinal knowledge of the community. OBJECTIVE: This study aimed at documenting herbal medicine and the associated knowledge from Koneba district of Afar Regional State, Ethiopia. METHODS: Purposive sampling method was used to select study sites and key informants. General informants were selected through simple random sampling methods. Semi-structured interviews and guided field walk were used to collect data while Informant Consensus Factor (ICF), Fidelity Level (FL) and Preference Ranking were used to analyze and verify data. RESULTS: A total of 67 medicinal plant species used to treat humans and livestock ailments were recorded and collected. Thirteen medicinal plant species were mentioned as effective medicine against snake bite (ICF; 0.68) while nine species used to treat malaria, common cold and fever (ICF: 0.67). Cyphostemma adenocaule (Steud. ex A.Rich.) Desc. ex Wild & R.B.Drumm. was the most preferred species used to combat snakebite, which was prevalent in the area. CONCLUSION: Snake bite, malaria, common cold and fever are common health problems in the study area. Efficient use of herbal medicine has minimized the impact of these diseases.

Micronutrient composition and microbial community analysis across diverse landraces of the Ethiopian orphan crop enset.

Enset (Ensete ventricosum) is a major starch staple and food security crop for 20 million people. Despite substantial diversity in morphology, genetics, agronomy and utilization across its range, nutritional characteristics have only been reported in relatively few landraces. Here, we survey nutritional composition in 22 landraces from three enset growing regions. We present mineral characterization of enset corm tissue, free amino acid characterization of raw and processed (fermented) tissues and genomic analysis of the microbial community associated with fermentation. We show that compared to regionally important tubers and cereals, enset is high in calcium, iron, potassium and zinc and low in sodium. We report changes in free amino acid composition due to processing, and establish that the bacteria genera Acetobacter, Lactobacillus and Bifidobacterium, predominate during fermentation. Nutritional and microbial variation presents opportunities to select for improved composition, quality and safety with potentially significant impacts in food security and public health.

Afro-alpine flagships revisited: Parallel adaptation, intermountain admixture and shallow genetic structuring in the giant senecios (Dendrosenecio).

Distantly related lineages of the enigmatic giant rosette plants of tropical alpine environments provide classical examples of convergent adaptation. For the giant senecios (Dendrosenecio), the endemic landmarks of the East African sky islands, it has also been suggested that parallel adaptation has been important for within-lineage differentiation. To test this hypothesis and to address potential gene flow and hybridization among the isolated sky islands, we organized field expeditions to all major mountains. We sampled all currently accepted species and all but one subspecies and genotyped 460 plants representing 109 populations. We tested whether genetic structuring corresponds to geography, as predicted by a parallel adaptation hypothesis, or to altitudinal belt and habitat rather than mountains, as predicted by a hypothesis of a single origin of adaptations. Bayesian and Neighbor-Net analyses showed that the main genetic structure is shallow and largely corresponds to geography, supporting a hypothesis of recent, rapid radiation via parallel altitude/habitat adaptation on different mountains. We also found evidence for intermountain admixture, suggesting several long-distance dispersals by wind across vast areas of unsuitable habitat. The combination of parallel adaptation, secondary contact, and hybridization may explain the complex patterns of morphological variation and the contradicting taxonomic treatments of these rare enigmatic giants, supporting the use of wide taxonomic concepts. Notably, the within-population genetic diversity was very low and calls for increased conservation efforts.

Genetic structuring, dispersal and taxonomy of the high-alpine populations of the Geranium arabicum/kilimandscharicum complex in tropical eastern Africa.

The scattered eastern African high mountains harbor a renowned and highly endemic flora, but the taxonomy and phylogeographic history of many plant groups are still insufficiently known. The high-alpine populations of the Geranium arabicum/kilimandscharicum complex present intricate morphological variation and have recently been suggested to comprise two new endemic taxa. Here we aim to contribute to a clarification of the taxonomy of these populations by analyzing genetic (AFLP) variation in range-wide high-alpine samples, and we address whether hybridization has contributed to taxonomic problems. We identified only two genetic groups. One corresponded to G. kilimandscharicum, which has been reported as exclusively high-alpine and confined to the eastern Rift mountains in East Africa. The other corresponded to G. arabicum, reported from lower altitudes on the same mountains as well as from a wide altitudinal span in Ethiopia and on the western Rift mountains in East Africa. The four populations analyzed of a recently described species from the Bale Mts in Ethiopia were admixed, indicating that they result from recent long-distance dispersal of G. kilimandscharicum from East Africa followed by hybridization with local G. arabicum in naturally disturbed habitats. Some admixture between the two genetic groups was also inferred on other mountains, supporting earlier suggestions of introgression based on morphology. We did not find support for recognition of the recently suggested new subspecies of G. arabicum in Ethiopia. Interestingly, the high-alpine G. kilimandscharicum lacked clear geographic structuring, suggesting a recent history of colonization of the different mountains or extensive intermountain gene flow.

Sweet vernal grasses (Anthoxanthum) colonized African mountains along two fronts in the Late Pliocene, followed by secondary contact, polyploidization and local extinction in the Pleistocene.

High tropical mountains harbour remarkable and fragmented biodiversity thought to a large degree to have been shaped by multiple dispersals of cold-adapted lineages from remote areas. Few dated phylogenetic/phylogeographic analyses are however available. Here, we address the hypotheses that the sub-Saharan African sweet vernal grasses have a dual colonization history and that lineages of independent origins have established secondary contact. We carried out rangewide sampling across the eastern African high mountains, inferred dated phylogenies from nuclear ribosomal and plastid DNA using Bayesian methods, and performed flow cytometry and AFLP (amplified fragment length polymorphism) analyses. We inferred a single Late Pliocene western Eurasian origin of the eastern African taxa, whose high-ploid populations in one mountain group formed a distinct phylogeographic group and carried plastids that diverged from those of the currently allopatric southern African lineage in the Mid- to Late Pleistocene. We show that Anthoxanthum has an intriguing history in sub-Saharan Africa, including Late Pliocene colonization from southeast and north, followed by secondary contact, hybridization, allopolyploidization and local extinction during one of the last glacial cycles. Our results add to a growing body of evidence showing that isolated tropical high mountain habitats have a dynamic recent history involving niche conservatism and recruitment from remote sources, repeated dispersals, diversification, hybridization and local extinction.

Colonization and diversification in the African 'sky islands': insights from fossil-calibrated molecular dating of Lychnis (Caryophyllaceae).

The flora on the isolated high African mountains or 'sky islands' is remarkable for its peculiar adaptations, local endemism and striking biogeographical connections to remote parts of the world. Ages of the plant lineages and the timing of their radiations have frequently been debated but remain contentious as there are few estimates based on explicit models and fossil-calibrated molecular clocks. We used the plastid region maturaseK (matK) and a Caryophylloflora paleogenica fossil to infer the age of the genus Lychnis, and constructed a data set of three plastid (matK; a ribosomal protein S16 (rps16); and an intergenic spacer (psbE-petL)) and two nuclear (internal transcribed spacer (ITS) and a region spanning exon 18-24 in the second largest subunit of RNA polymerase II (RPB2)) loci for joint estimation of the species tree and divergence time of the African representatives. The time of divergence of the African high-altitude Lychnis was placed in the late Miocene to early Pliocene. A single speciation event was inferred in the early Pliocene; subsequent speciation took place sporadically from the late Pliocene to the middle Pleistocene. We provide further support for a Eurasian origin of the African 'sky islands' floral elements, which seem to have been recruited via dispersals at different times: some old, as in Lychnis, and others very recent. We show that dispersal and diversification within Africa play an important role in shaping these isolated plant communities.

Ethnobotanical study of medicinal plants around 'Dheeraa' town, Arsi Zone, Ethiopia.

A study aimed at identifying plant species used and manipulated by the community for medicine was carried out around 'Dheeraa' town, Arsi Zone, Oromia Region, Southeast Ethiopia. The data were collected through a series of fieldworks conducted from October to December 2002. Random and systematic sampling methods were employed to select the study sites as well as the informants. Ethnobotanical methods using semi-structured interviews were employed and a total of 83 species of medicinal plants were recorded. The natural environment yielded larger proportion (76 species, 92%) of the total records followed by home gardens of the area. The studied medicinal plants were those used in traditional health care of humans and livestock. However, only very few individuals of each species were found in the area and this might be attributed to the ongoing habitat modification and loss of natural vegetation. Therefore, it is important to create awareness on sustainable use of the natural vegetation. Paying special attention to the medicinal plants found in the area may help to amplify the role that these plants play in healthcare, poverty alleviation as well as environmental protection.