Effect of pre-sowing treatments on seed germination and seedling growth of silver butterfly tree (bauhinia rufescens)

Abstract

Three experiments were conducted in a plastic greenhouse at the Sinna Garden of the Crop Science Department of the University of Ghana, Legon, Accra to investigate into pre-sowing treatment (water treatment, growth regulator, and sulphuric acid scarification and water soaking) effects on seed germination and seedling growth of Bauhinia rufescens from October to December, 2011 and January to April, 2012, respectively. The experimental design used was complete randomized design. There were 4 treatments in experiment 1, 7 in experiment 2 and 6 in experiment 3. Each experiment was replicated five (5) times. The results showed that Bauhinia rufescens seeds soaked in hot water at 65 0C for 60 minutes gave the highest mean germination rate, tallest plant height and highest number of leaves per plant at 49 days after soaking. It also had the widest stem diameter, highest fresh shoot and root weight, highest fresh root and dry root weight and number of roots per seedling. Seeds soaked in 500 ppm Gibberelic acid (GA3) produced the highest number of leaves per plant and tallest plants at 49 DAS. Seeds soaked in 750 ppm GA3 had the highest number of leaves per plant at 49 DAS and highest fresh shoot weight. Seeds soaked in 1000 ppm Promalin differed significantly from 500 ppm GA3 and the control in germination percentage. Seeds soaked in 1000 ppm Promalin differed significantly from 500 ppm GA3 and the control in germination percentage. Acid scarified seeds for 60 minutes plus soaking in tap water for 24 hours differed significantly from the seeds treated with other growth regulator rates plus 24 hours soaking in germination percentage. Acid scarified seeds for 45 minutes plus soaking in tap water for 24 hours had the tallest plant and highest number of leaves per plant at 49 DAS, widest stem diameter, highest fresh shoot and root weight and dry shoot weight. Soaking seeds in hot water at 65 0C for 60 minutes and/or in acid (H2SO4) for 45 minutes plus soaking in tap water for 24 hours is recommended as pre-sowing treatment for Bauhinia rufescens for maximum mean germination rate and vigorous vegetative growth of seedlings