Germination studies on seeds of trichilia emetica and vangueria infausta

Masters in Forestry

The effect of various physical seed coat scarifications and chemical treatments were studied to determine presowing prescriptions that would ensure uniform, fast and high germination in seeds of Trichi Iia emetica and Vangueria infausta. The studies involved eight 3x5 factorial model experiments arranged in a randomized block design with with 4 blocks each. For each of the two species, two different experiments were conducted in the laboratory and repeated in the nursery. The first experiment of Tri chi Iia erne t i ca involved 3 types of physical seed coat scarification and soaking the seeds in gibberellic acid (CA3) at 5 concentrations; i.e. 0, 250, 500, 750, and 1000 ppm. A second experiment involved 3 types of physical seed coat scarification and soaking the seeds in potassiun nitrate (KNO^) at 5 concentrations; i .e. 0.0, 0.2, 0.4,0.6 and 0.8%. The first study involving Vangueria infausta included 3 types of physical seed coat scarification and treatments of the seed with 5 concentration levels of hydrogen peroxide (H202); i .e. 0, 2, 4, 6 and 8%. In the second experiment, 3 types of physical seed coat scarifi- cation and soaking the seeds in 5 concentration levels of indole acetic acid (IAA); i.e. 0, 25, 50, 75 and 100 ppm were studied. Unscarified seeds of Trichi Iia emetica (without chemical treatment) atta­ ined cumulative germination of 29% and 35%, while seeds with complete removal of both the aril and the seed coat attained cunulative germination of 94s and 93« in the laboratory and nursery experiments respectively.