Analysis of population structure, soil physicochemical properties and phytochemical profile of prunus africana (Hook. F) Kalkman in Nyika national park, Malawi and Zambia

Abstract

Prunus africana is an important medicinal plant and its population is declining in most of its natural range because of over-exploitation. Its bark is processed by pharmaceutical companies in Europe to treat Benign Prostatic Hyperplasia (BPH). Little is known about the status of Prunus africana in Malawi. Therefore, the research was conducted to investigate the population structure, soil preference, and phytochemicals of Prunus africana in Nyika National Park, Malawi and Nyika National Park, Zambia. The data was collected using belt transects. Data on species name, height (m), dbh (cm), canopy cover, soil and tree bark samples were collected at random. The data was analysed using GenStat, past 4.03, Mintab and PC-ORD statistical software. The study recorded 5 trees/ha in both study sites. Juniper Forest had the highest mean density (14 trees/ha) while Manyenjere Forest recorded a density of (4 trees/ha). There were more mature trees than saplings and seedlings across the study area, and Manyenjere had no seedlings at all. This was attributed to the thick canopy cover in Manyenjere, as the species is a light demander. Soil analysis revealed that all essential elements (Ca, N, Mg, pH, and C) were the same in both sites except phosphorus which varied significantly (p<0.05) between the Juniper Forest (9.01±4.7 mg/kg) and Manyenjere Forest (3.83 ±3.4 mg/kg). Most phytochemical compounds known to treat BPH such as β-sitostenone, γ-Sitosterol, ursolic acid, and Apigenin 6-c--glucoside were detected. It was concluded that both sites are dominated by mature trees with very little or no recruitment at all which is due to limited disturbances (Geldenhuys and Venter 2002). It was, therefore, recommended that pruning in thick forest be promoted to allow light into the forest floor to trigger regeneration. Further research to assess the impacts of pests on the regeneration of Prunus africana is needed