Enhancing the germination of fresh seeds of Bowiea volubilis, a widely used bulbous medicinal plant : research in action

We have investigated methods to enhance seed germination of Bowiea volubilis , a widely used medicinal plant. Owing to their hard coat, which inhibits germination, seeds were subjected to mechanical scarification (using sandpaper) and chemical scarification (using concentrated H 2 SO 4 and H 2 O 2 ) for different lengths of time. The effect of temperature on germination was also investigated. The percentage germination under control conditions (25 o C) was only 15% with a mean germination time of 18 days. Scarification with concentrated HlSUBg2l/SUBgSOlSUBg4l/SUBg resulted in 73% germination after 4 days but seeds were then highly susceptible to fungal infestation, resulting in severe loss of young seedlings. Scarification with HlSUBg2l/SUBgOlSUBg2l/SUBg slightly improved the germination rate (30%). The seeds incubated at 20 o C resulted in higher germination (90%) than at other temperatures tested, but required a mean germination time of 25 days. In continuous darkness at room temperature, 88% of seeds germinated with a mean germination time of 24 days. Mechanical scarification with sandpaper proved to be the best treatment to enhance germination, which reached 100% within a mean germination time of only 6 days.