Functional Roles of Seed Mucilage of Capsella Bursa-Pastoris L. on Seed Germination and Dispersal

The seed mucilage of some plant species is suitable for use in dry regions because of its water-retaining properties. However, the role of mucilage in plants growing in humid regions has not yet been fully elucidated. In the present study, we investigated the effect of seed mucilage in Capsella bursa-pastoris (L), which grows in temperate humid regions, on seed germination and dispersal. Seeds with mucilage had higher germination rates than those without mucilage. This suggests that seed mucilage may be related to the dormancy of C. bursa-pastoris seeds. In addition, our study revealed that under conditions where dormancy was broken by temperature alteration, seeds with mucilage germinate 1–2 days later than seeds without mucilage. In a walking experiment in which seeds with vesicles were attached to shoes, 61.4% of the seeds were carried a distance of 500 m. From these results, it is suggested that the seed mucilage of Capsella bursa-pastoris functions in adhesion and dispersal and also may delay germination during the period when the seeds are moving.