This study was conducted to determine the effects of different caffeine concentrations on seed germination of Bambara groundnut. The seeds were pre-soaked in distilled water for 12 hours and then exposed to the different concentrations of the caffeine doses prepared on weight basis, i.e. 0.005 %, 0.25 %, 0.5 %, and 0.75 % 1.0 %, 1.25 %, 1.5%, 1.75% and 2.0% w/w caffeine in solution, prepared in a phosphate buffer of pH-7 2. Three replications of the treatments were made and sown with each seed of the treated concentrations in a pot using a Complete Randomized Block Design (CRBD). Seed germination was scored for seven days and the germinated seedlings were further observed for 9 weeks. The radicle length, shoot height, and stem girth were measured weekly after germination. From the results, it was evident that increased concentration of caffeine reduced the germination percentage of the seeds. The caffeine concentrations of 1.75-2.0% recorded no germination compared with more than 90% germination at the end of the 7 days recorded in the case of 0.05-0.25% caffeine concentrations. There was a reduction in radicle length as the caffeine concentration increased at 7 weeks after planting. 0.5% caffeine concentration recorded the highest shoot length of 3.32cm among the caffeine concentrations with no significant difference detected in the stem girth studied. From the results obtained therefore, lower caffeine concentrations showed an increase in Bambara groundnut germination, hence could result in general improvement in crop yield.

Plant growth regulators (PGRs) are natural hormones found in plant or their synthetic hormone analogues. Auxin, a type of PGRs that consist of low molecular weight organic phytohormones which influences cell division, plant growth and development. One of the common auxin types is indole-3-acetic acid (IAA) and was the first plant growth regulator to be discovered with characteristics that involved in the control of various plant growth and development.Auxins can be absorbed in tissues and transport to long distances throughout vascular tissueof a plant. Therefore, this study aimed to investigate the influence ofIAA on the treated seeds of cowpea (VignaunguiculataL.Walp) accession TVu-7, TVu-9 and TVu-1945to 50 % seed germination, seedling growth and development, and leaf chlorophyll content.The various IAA concentration used were 0mg/L, 250mg/L, 500mg/L 750mg/L and 1000mg/L. The results of this study showed the relative effect of various concentrations of IAA on seed germination, vegetative structure produced and leaf chlorophyll content. For example, increased IAA concentrations of 1000mg/L further extend the number of days to attend 50 % seed germination in the different cowpea accessions. Also, an increased concentration to 1000mg/L significantly increased the leaf chlorophyll content in the different cowpea accessions.