Allanblackia Species: a Model for Domestication of High Potential Tree Crops in Africa

Allanblackia is a dioecious multipurpose tree genus of the family Clusiaceae occurring in the equatorial rainforests of Africa, extending from Tanzania to Sierra Leone. Besides its traditional main use for producing edible oil from its seeds, local communities use Allanblackia species as medicine and timber. A few years ago, the food processing industry discovered Allanblackia oil with its specific exceptional characteristics as a new ingredient in the sustainable manufacture of products such as margarine. Currently the potential market demand for Allanblackia oil (estimated at over 100,000 tons/year) cannot be met by harvesting fruits of wild Allanblackia species (A. floribunda in Nigeria, A. parviflora in Ghana and A. stuhlmannii in Tanzania), which yield a total of only 210 tons/year from all the three countries. To address this and the challenges of over-exploitation and decreasing Allanblackia abundance in the forests, ICRAF and its partners from the public and private sector have been domesticating the species since 2002 using a participatory tree domestication approach. The program includes community sensitization, exploration, participatory selections of superior mother trees, conservation in field genebanks, development of agroforestry systems with Allanblackia and market development. Secondly, the program consists of developing asexual and sexual propagation protocols, which are necessary to overcome challenges in multiplication such as seed dormancy, long juvenile phase and high variability of desired traits. Experiments are mainly performed in 'Rural Resource Centres' (RRCs), which serve as diffusion hubs for new technologies, germplasm and knowledge. RRCs have their own tree nurseries, motherblocks and demonstration plots, and train farmers in Allanblackia propagation and cultivation techniques. The domestication programme of Allanblackia through public-private partnership and participatory tree domestication could serve as a model for domestication of other underutilized African tree species of high economic potential.