EFFECTS OF SEED SIZE AND PHYTHORMONE ON THE GERMINATION OF SEEDS OF TWO FOREST TREE SPECIES, Prosopis africana Guil AND Dialum guineensis Wild.

Abstract

Studies were conducted on the effect of seed sizes and phytohormone (GA3) on seed germination of two savanna tree species: Prosopis africana (Guil) and Vialum guineensis (Wild). The selection of the seeds was based on the role they play in the savanna community and nutrient recycling of soil. The trees, like many others are fast going into extinction. The seeds of these species were found to be dormant while the seedlings also have high mortality rates. The two tree species produce two seed types, large and small. The Gibberellic acid at 3000mgll had

significant effect (P :::; 0.05) on seed germination in both P. africana and D. guineensis. The large and small seeds of two tree species evaluated had up to 80 and 30 to 50% germination; respectively. Termination of hard seed coat was obtained under 10-15 minutes treatments, and gave up to 70-80 percentage germination in D. guineensis and P.

Africana seeds. Gibberellic acid at l000mgIL-3000rngIL gave maximum percentage seed germination of 60-80% while'untreated seeds did not germinate at all. The experimental design used was the randomized block type. All treatments were in five replicates