Effects of four pre-sowing treatment methods (double phase) on the germination of the seeds of <i>Afzelia africana</i> Sm. ex Pers

Abstract

The study investigated the effects of four pre-treatment methods on the germination response of the seeds of Afzelia africana (Sm. ex Pers) in the savannah ecozones of Nigeria. The experiment was carried out in two phases. Phase I involved; 50% concentrated sulphuric acid for 10 minutes, hot water at 100ºC for 3 minutes, cold water at room temperature for 24 hours, Mechanical scarification (rubbing on abrasive concrete surface). Phase II of the experiment was carried out based on the result of phase I. Mechanical scarification, which performed best among the treatments used in the first phase, was closely examined. The various mechanical scarifications used were rubbing the seeds on abrasive concrete surface to the length of 1mm into the seed coat, 2mm, 3mm and 4mm. The experimental layout used was Completely Randomized Design. For phase I, mechanical scarification had 25% germination rate and had the highest germination compared to other treatments. Due to the performance of mechanical scarification in phase I, varying mechanical scarification treatments were further investigated in phase II of the experiment. The result of the analysis of variance indicated a significant difference between the varying mechanical scarification treatments (p≤0.05). Separation of the means showed that 1mm mechanical scarification treatment differed significantly from all other treatments. 1mm mechanical scarification treatment gave an average germination of 50% and early emergence of 9 days. Therefore, 1mm mechanical scarification treatment was regarded as the best mechanical scarification treatment for the germination of Afzelia africana seeds.

Keywords: pre-treatment, dormancy, germination, Afzelia africana