Introduction.Garcinia kola, a multi-purpose fruit tree, produces fruit, seeds,
roots and stem which are extensively used in Nigeria, Ghana and other West African countries
for dental care. Cultivation of this fruit tree is limited because of poor seed germination.
Our study therefore aimed at improving seed germination properties which will promote
cultivation of G. kola by rural farmers. Materials and methods. Seeds taken from a single
tree of G. kola were treated with cold water (22 °C), hot water (60 °C) and gibberelic
acid (0.5 g × L-1) for various lengths of time. They were then put to incubate in sterilized
river sand or a thick transparent polyethylene bag to evaluate the capacities of seed to
be germinated under such conditions. In addition, the seed moisture content at harvest
was also reduced to various levels before incubation in polyethylene bags to determine
the critical moisture rate necessary for seeds to germinate. Results. The seeds incubated
in the river sand without any treatment before sowing had an average time of germination of
71.2 d and a total percentage of germination of 28% whereas those incubated in polyethylene
bags had an average time of germination of 25.8 d and a total percentage of germination
of 62% . The cold water treatment, irrespective of the incubation method, did not
significantly affect either the mean germination time or the total germination percentage.
However, it significantly reduced the spreading out of the seed germination to 5.4 d.
The seed pretreatment with gibberelic acid prolonged at the same time the average time
of germination and the spreading out of the germination. The seed water content at
harvest (50.4%) allowed the best rate of seed germination and the shortest spreading
out of the germination period. Conclusion. The pretreatment of freshly harvested seeds
with cold water followed by an incubation in a thick transparent polyethylene bag proved
most effective in enhancing the germination of G. kola seeds. This procedure has to be
recommended to promote the cultivation of this species.
