Uses and management of black plum (Vitex doniana Sweet) in Southern Benin.

Garcinia kola (Heckel) is a versatile tree indigenous to West and Central Africa. All parts of the tree have value in traditional medicine. Natural populations of the species have declined over the years due to overexploitation. Assessment of genetic diversity and population structure of G. kola is important for its management and conservation. The present study investigates the genetic diversity and population structure of G. kola populations in Benin using ultra-high-throughput diversity array technology (DArT) single nucleotide polymorphism (SNP) markers. From the 102 accessions sampled, two were excluded from the final dataset owing to poor genotyping coverage. A total of 43,736 SNPs were reported, of which 12,585 were used for analyses after screening with quality control parameters including Minor allele frequency (� 0.05), call rate (� 80%), reproducibility (� 95%), and polymorphic information content (� 1%). Analysis revealed low genetic diversity with expected heterozygosity per population ranging from 0.196 to 0.228. Pairwise F-statistics (F ST) revealed low levels of genetic differentiation between populations while an Analysis of molecular variance (AMOVA) indicated that the majority of variation (97.86%) was within populations. Population structure analysis through clustering and discriminant analysis on principal component revealed two admixed clusters, implying little genetic structure. However, the model-based maximum likelihood in Admixture indicated only one genetic cluster. The present study indicated low genetic diversity of G. kola, and interventions are needed to be tailored towards its conservation.

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Erythrina abyssinica (E. abyssinica) is a multipurpose tree and a well-known medicinal plant which is conventionally propagated mainly by seeds. This method may produce a high degree of genetic variability and consequently decrease the medicinal value of the plant. Besides, the seeds have low germination rate and propagation is restricted to rainy season. Hence, there is need to develop a propagation protocol which produces a uniform plants and one which is not restricted to seasons. The objective of this study was to establish an in vitro propagation protocol for the multiplication of E. abyssinica. Seeds were sterilized and germinated in vitro to get sterile starting explants. Sterilization of the seeds was evaluated using different concentrations of a commercial bleach (JIK) ranging from 10%, 20% to 30% for 25 minutes. Kinetin (2.25, 4.50, 6.75, and 9.0 mg/L), and benzylaminopurine (BAP; 2.15, 4.30, 6.46, and 8.61 mg/L) were evaluated in separate experiments for their effect to induce microshoots from nodal explants. Rooting of the microshoot was carried out using half strength Murashige and Skoog (MS) media supplemented with indolebutyric acid (IBA) (0.20, 0.51, and 1.02 mg/L). Statistical analysis software (SAS) package was used to perform analysis of variance on the data to test the significance of the difference between treatments. The result of the sterilization experiment indicated that 10% JIK gave the highest percentage (55%) of clean seeds. Benzylaminopurine evaluated at 8.61 mg/L gave the highest mean number of microshoots (6.80 ± 1.24) after 28 days. On the other hand, IBA evaluated at 0.51mg/L gave the highest mean root length (6.00 ± 01.85 cm). The regenerated plants were acclimatized in the greenhouse and 65% survival rate was recorded after one month. With the increasing worldwide demand for medicinal plants as an alternative to prescription drugs, ex situ, in situ conservation programs and true to type mass propagation of E. abyssinica could benefit from the findings of this study. This is the first report on micropropagation of E. abyssinica.

Background Cassava is a staple food for over 800 million people globally providing a cheap source of carbohydrate. However, the cultivation of cassava in the country is facing to viral diseases, particularly cassava mosaic disease (CMD) which can cause up to 95% yield losses. With aim to supply farmers demand for clean planting materials, there is need to accelerate the production of the elite cultivars by use of tissue culture in order to cope with the demand.Methods Nodal explants harvested from the greenhouse grown plants were sterilised using different concentrations of a commercial bleach JIK (3.85% NaOCl) and varying time intervals. Microshoots induction was evaluated using thidiazuron (TDZ), benzyl amino purine (BAP), and kinetin. Rooting was evaluated using different auxins (Naphthalene acetic acid NAA and Indole-3-butyricacid IBA). PCR-based SSR and SCAR markers were used to verify the presence of CMD2 gene in the regenerated plantlets.Results The highest level of sterility in explants (90%) was obtained when 20% Jik was used for 15 minutes. The best cytokinin for microshoots regeneration was found to be kinetin with optimum concentrations of 5, 10 and 20 µM for Agric-rouge, Atinwewe, and Agblehoundo respectively. Medium without growth regulators was the best for rooting the three cultivars. A survival rate of 100%, 98%, and 98% was recorded in the greenhouse for Agric-rouge, Atinwewe, and Agblehoundo respectively and the plantlets appeared to be morphologically normal. The SSR and SCAR analysis of micropropagated plants showed a profile similar to that of the mother plants indicating that the regenerated plantlets retained the CMD2 gene after passing through in vitro culture, as expected with micropropagation.Conclusion The nodal explants was established to be 20% of Jik (3.85% NaOCl) with an exposure time of 15 minutes. Kinetin was proved to be the best cytokinins for microshoot formation with the optimum concentration of 5, 10 and 20µM for Agric-rouge, Atinwewe, and Agblehoundo respectively. The protocol developed during this study will be useful for mass propagation of the elite cassava cultivars.