Influence of different pretreatments on seed germination and growth rate of <i>Adansonia digitata</i> (Aaertn) seedlings

Abstract

Adansonia digitata is an important medicinal and economic species. However, the seed dormancy is a factor to its domestication and natural regeneration. The study was carried out to investigate the effects of pretreatment on the germination and growth response of Adansonia digitata. The study was carried out at Forestry Nursery, University of Agriculture Makurdi. The seeds were immersed in cold water at 25^oC for 6hrs, hot water or 100^oC for 10min. and 98% sulphuric acid at 1hr and sown without treatment(control) and replicated thrice. After the pretreatment, the seeds were sown in 15 x 13cm polypots filled with top soil. Completely Randomized Design was adopted for the experiment. The experiment lasted for 8 weeks. Data was collected on day of emergence, germination percentage, number of leaves, plant height and length on weekly basis. Analysis of Variance (ANOVA) was employed for the analysis. Duncan Multiple Range Test(DMRT) was used for mean separation. The results revealed that H₂SO₄ at 98% for 1hr emerged earlier on the 4^th day after sowing. Also from the findings, H₂SO₄ was seen to enhance germination percentage(93.33%)and growth performance in terms of plant height (15cm), number of leaves (6) and leaf length (6cm) respectively The rest treatment did not show any significant difference on the seed germination and growth rate. Based on the findings, it is concluded that to raise a large scale of Adansonia digitata seedlings in the nursery for conservation purposes, pretreatment of seeds in 98% H₂SO₄ for 1hr should be adopted.

Keywords: Pretreatment, germination, growth response, Adansonia digitata