Effects of pre-germination treatments on seed germination of Swaziland and Nigerian okra (Corchorus olitoriusl.) land races

摘要

Bush okra {Corchorus olitorius L.) has a potential for production as a major traditional leafy vegetable crop consumed in many parts of Africa. It is generally propagated by seeds. However, the low germination rate of seeds harvested from the previousseason is a big challenge. Wild okra seeds were thus treated with different pre-germination treatments. Seeds with a seed viability of 88.9% (determined using the Tetrazolium technique), were exposed to seven pre-treatments; water at room temperature (control), hot water at 100°C, sulphuric acid (98%), dry heat at 80°C, physical scarification, chilling at 6°C and freezing for 15 min. Soaking seeds in boiling water at 100°C for 10 s was effective in enhancing a maximum germination of 84.7% on Swaziland okra. The Nigerian okra seeds had 79.1% germination after being subjected to dry heat at 80°C for 15 min. The seeds soaked in sulphuric acid (98%) for 15 min, resulted in 21.1% germination for Swaziland okra while the Nigerian okra achieved 20.8% germination. Scarification by rubbing the seeds with sand paper was found to be less effective, achieving 2.8% germination for Swaziland okra and 5.3% germination for Nigerian okra, while chilling and freezing gave varying less effective results between 1.6 and 16.9%, respectively. Soaking of okra seeds in boiling water for 10 s can thus be recommended as the most effective treatment for enhancing germination of okra seeds. This is also a relatively simple and cheap method.