Seed dormancy and germination of Vicia sativa subsp nigra and Vicia sativa subsp macrocarpa

Abstract

The objectives of this study were to determine the changes in seed dormancy for a year following harvest and to ascertain the effects of different treatments on the germination of seeds of Vicia sativa subsp. nigra and Vicia sativa subsp. macrocarpa. After scarification, the germination rates of V. sativa subsp. nigra seeds increased from c. 40% to 99 and 95% for seeds harvested in 2008 and 2009, respectively, and did not vary through the year. This shows that the dormancy was caused by a hard seed coat. The germination rates of untreated (control) V. sativa subsp. macrocarpa seeds was <= 5% throughout the year following harvest, for seeds harvested in both 2008 and 2009. After either mechanical scarification or chilling treatment, the average germination rates were 10 and 22% for seeds harvested in the different years. However, the combined scarification and chilling treatment resulted in germination rates of 73% for seeds harvested in 2008 and 74% for those harvested in 2009. This indicates that the seeds had physiological dormancy as well as impermeable seed coats.