Effect of pre-germination treatment on germination of Zizyphus mauritiana and Zizyphus spina-christi seeds in a semi arid environment of Sokoto-Nigeria

Abstract

Effect of three seed treatment methods (mechanical seed scarification, sulphuric acid and hot water) were investigated on germination of Zizyphus mauritiana and Zizyphus spina-christi. Floatation method was used to separate viable seeds form non-viable ones. Mechanical scarification was carried out at three seed sites, (2mm from microphyle, 2mm from distal end and around the circumference) for the two species. In sulphuric acid treatment, 98% concentration was used at three varying periods of immersion (10 minutes, 30 minutes and 60 minutes) for both species. Similarly hot water (100⁰C) treatment was carried out at three varying immersion time (15, 30 and 45 minutes). Untreated seeds were also used as control in each case. Seeds which were mechanically scarified around the circumference had higher germination percentage of 76.7%, and 73.3% for Z. mauritiana and Z. spina-christi respectively. In both species, poor germination percentage was obtained from mechanical scarification at 2 mm from the distal end in the two species with 46.7% and 43.3% for Z. mauritiana and Z. spina-christi respectively. A higher germination percentage was recorded from seeds immersed for 10 and 30 minutes with 80% each for Z. mauritiana and 60% and 66.7% from seed immersed at 10 and 30 minutes respectively for Z. spina-christi . There was no germination in seeds treated with hot water in the two species. Thus, hot water treatment was found incompatible with the species. Interestingly untreated seeds (control), showed good germination response. However, it inferred from this study that, mechanical scarification and concentrated sulphuric acid treatments are some the factors that significantly influence germination percentage in seeds of Z. mauritiana and Z. spina-christi