Exploration and Assessment on the Agronomic Requirement of Taverniera abyssinica A. Rich: A Critically Endangered Medicinal Plant of Ethiopia

We determined the distribution and abundance of Taverniera abyssinica A. Rich in the Shewa floristic region, Ethiopia. We also carried out a mesh-house experiment to know whether T. abyssinica is able to survive and grow in any soil. From the nine potential locations we made exploration, T. abyssinca populations were found only in the two, Lemen and Mojo. The abundance of mature individuals was estimated to be more than 600/hectare. The one-way ANOVA results indicated that soil does not have a significant (p>0.05) effect on seedlings survival rate. However, it was found to have significant (p<0.05) effects on seedlings growth, root nodulation, and root arbuscular mycorrhizal fungi colonization. Seedlings grown on the soil collected from Lemen and Mojo produced significantly (p<0.05) more number of leaves and grew better than those grown on Addis Ababa (where the species was never reported to grow) soil. The root fresh weight of seedlings grown on Addis Ababa soil was found to be significantly (p<0.05) and 38.89% and 54.17% lower than the root fresh weight of seedlings grown on Lemen and Mojo soils respectively. We report that T. abyssinica is N-fixer and arbuscular mycorrhizal. Seedlings grown on the Addis Ababa soil were not colonized by arbuscular mycorrhizal fungi while those grown on Lemen and Mojo soils were. Although the estimated abundance of mature T. abyssinica individuals was high, there is continued exploitation of the species and habitat loss is imminent. Therefore, integrated conservation program by way of ex situ conservation, in situ conservation, and cultivation should be implemented. Taverniera abyssinica could be cultivated in areas with leptosol and degraded vertisol soils with slightly acidic to basic pH. Arbuscular mycorrhizal fungi could play key role in future conservation and cultivation efforts of the species.