Brita Stedje

This study aimed at evaluating the phytochemical, nutritional and cytotoxicity of Dipcadi glaucum, a wild edible species in Zimbabwe. The results of the proximate analysis show that D. glaucum is rich in nutrients, with high levels of crude protein (26.6% in leaves and 24% in bulbs) and ash (26.25% in leaves and 14% in bulbs), alongside moderate carbohydrate levels (35.55% in leaves and 43% in bulbs) and calorific values (295.6 kcal/100 g in leaves and 310.9 kcal/100 g in bulbs). The phytochemical analysis established presence of alkaloids, tannins, flavonoids, terpenoids, saponins, and steroids, suggesting potential health benefits and culinary applications Cytotoxicity was assessed using the brine shrimp lethality assay, showing an LC50 of 2.72 mg/ml for methanol bulb extracts and 1949.85 mg/ml for aqueous extracts. While both extracts were non-toxic based on assay thresholds, reports of potential toxicity to ruminants and the presence of alkaloids at higher concentrations warrant further research. Findings of this study suggest that D. glaucum is an important nutritional and mineral supplement, though additional research is needed to confirm its safety and suitability for human consumption.

Species circumscriptions in the genus Dipcadi were evaluated based on both morphological and molecular data, with an emphasis on African taxa. DNA was extracted and the ITS region amplified for 33 Dipcadi accessions, and an additional 18 ITS sequences were obtained from GenBank. Phylogenetic analyses based on Maximum Likelihood and Bayesian Inference were congruent. The species D. marlothii and D. glaucum are recovered as monophyletic, and their status is also supported by morphological data. Other species are either paraphyletic (D. viride), polyphyletic (D. longifolium, D. serotinum, and D. erythraeum), or in unresolved clades with other taxa (D. gracillimum and D. platyphyllum). Future studies should include additional loci and more material to improve the resolution of species relationships and to properly delimit non-monophyletic taxa.

The phenological and morphological variation studies among forms of Laggera Sch. Bip. Ex. Benth. and Hook species are limited, despite the medicinal use of the genus. Therefore, this study aimed to document phenology and morphological variation in cultivated populations of Laggera alata and Laggera crispata forms from seedling to maturity. The forms were categorized as Laggera alata with a small capitulum (LA-SC), Laggera alata with a large capitulum (LA-BC), Laggera crispata from South Africa (LC-SA), and Laggera crispata from Zimbabwe (LC-ZIM). Seeds were germinated in Petri dishes, transplanted to plug trays, and later to field plots at 60 days. Phenological events were recorded when observed in at least one plant. Twelve qualitative and four morphometric traits were measured monthly on five plants per Laggera form. Analysis of variance and Tukey’s Honestly Significant Difference test (p < 0.05) were used for data analysis. Results indicated significant variation in phenology, qualitative traits, leaf traits, plant height, and stem diameter both within and between L. crispata and L. alata forms. Morphometric traits, such as leaf size and the number of leaves per plant, were identified as key descriptors for differentiating L. alata forms. These findings provide a foundation for the introduction of Laggera forms into farming systems for medicinal and commercial purposes.

This is a morphological study of 108 accessions of Solanum campylacanthum and 10 accessions of Solanum cerasiferum. The aim was to assess the morphological variations that occur within the S. campylacanthum species in Uganda and evaluate the morphological differences between S. campylacanthum and S. cerasiferum. Fourteen quantitative and eleven qualitative vegetative characters were measured and analysis done by phenetics method. Cluster (UPGMA) and box plot analyses were done in PAST program version 4.03. Prickle density and leaf tip angles are reported for the first time as being useful in the intraspecific delimitation of S. campylacanthum. The distinction between S. cerasiferum and S. campylacanthum can only be based on leaf base shapes, which is, attenuate and oblique respectively.

A new genus Occultia (Scilloideae, Asparagaceaae), is described from Malawi and Mozambique. One of the species on which this genus is based, was originally described as Hyacinthus. The genus is clearly separated from Ledebouria and closely related genera in characters of the flowers and the fruits. In Occultia tepals are united for 1/3 to ½ their length, the filaments are very short and inserted at the top of the perianth tube. In the fruiting stage, the tepals of the new genus become membranous and detached from their basis, but may form a cap on the developing capsule. In Ledebouria the tepals are free or united just at the base, the filaments are of a certain length and inserted at the base of the tepals. If persisting at fruiting stage the tepals are attached to the base of the capsule, and may become fleshy with time. The new genus comprises two species O. hyacinthoides and O. fragrans.

There are four species of Artemisia known in Ethiopia, namely A. schimperi (endemic), A. abyssinica, A. afra and A. absinthium (syn. A. rehan). All these species occurred naturally except A. absinthium, which usually grows in private gardens. The main objective of this study was to reconstruct the molecular phylogeny to determine phylogenetic positions of Ethiopian Artemisia species using the external and internal transcribed spacers (ETS, ITS). A total of 57 sequences (nine new and 48 retrieved from GenBank) were used in maximum parsimony (MP) and maximum likelihood (ML) analyses. The Ethiopian Artemisia species were recovered in three clades corresponding to subgenera (Artemisia, Absinthium and Pacifica). The sequences of Ethiopian A. absinthium (previously known as A. rehan) grouped with A. judaica and are distantly related to the European A. absinthium. Artemisia abyssinica and A. schimperi have affinities to A. subg. Pacifica with adaptations to a relatively cool and dry subalpine tropical climate.

The ability of taxa to cross/hybridize is useful information for plant systematists and breeders. Crossability reflects reproductive isolation and the biological species concept stresses the need for reproductive isolation between species to maintain morphological distincness. For plant breeders knowledge on crossing ability facilitate selection of taxa for character improvement breeding. In this study, the crossing relationships and chromosome numbers within and among Ugandan species of Solanum sect. Solanum is studied by making 800 crosses involving 246 combinations. Less than half of these combinations were successful, producing F1 offspring. All studied accessions are self‐compatible and most accessions crossed readily with accessions of their own species. Interspecific crossings failed either to yield seeds, yielded F1 seeds that did not germinate, or resulted in F1s that did not have stainable pollen – implying a crossing barrier; or stainable pollen, but with chromosome numbers that indicated reproduction by apomixis. The results support the taxonomic treatment of Solanum based on classical, numerical and partly molecular evidences. The material studied represents eight Ugandan taxa: S. americanum , a diploid (2n = 2x = 24); five tetraploids (2n = 4x = 48) S. florulentum, S. memphiticum, S. tarderemotum, S. villosum ssp. villosum and S. villosum ssp. miniatum ; and two hexaploids (2n = 6x = 72) S. scabrum subsp. scabrum and S. scabrum subsp. laevis . In addition to confirming the ploidy levels of the Ugandan accessions, the ploidy levels of S. florulentum, S. memphiticum and S. tarderemotum are reported for the first time. Non‐Ugandan material of Solanum sarrachoides was found to be diploid. Knowledge of the crossing behaviour and ploidy levels in Solanum will facilitate breeding for character improvement in these important species that are used commonly as food and/or medicine in eastern Africa.