Demand, propagation and seedling establishment of selected medicinal trees

Abstract

Short-listing of medicinal tree species for propagation was done through three criteria; number of bags sold, price per bag and mean scarcity value. There is a strong correlation between the mean scarcity values and number of bags sold per annum. On this basis, twenty three priority species were short-listed. Finally, seeds of only ten species were available and their propagation potential was investigated. Four species had moisture contents in the seeds of less than or equal to 20% and seven had moisture content of greater than or equal to 50%. Seed viability was 75% for all species using flotation and triphenyltetrazolium chloride (TTC) tests. Only E. lasianthum had 55% viability using the TTC test. The high percentage seed viability across different species indicates their probable high germination vigour and quality. Cracking pre-treatment significantly increased germination across all species (62%) However, cracked seeds need to be thoroughly sterilised to avert fungal infestation. Acid and hot water pre-treatments decreased germination relative to the control (21%). Three species in controlled growth experiments showed that leaf area was the most significantly affected factor between species grown in sun and 40% shade conditions. However, it was impossible to classify seedlings as sun- or shade-loving. Some of the forest seedlings remain stunted until gaps in the canopy allow them to grow and establish themselves quickly. It could be appropriate to recommend low or medium light intensity for the establishment of such seedlings.