2023 Volume 49 Issue 1 Pages 3-8
To determine whether Dianthus superbus var. longicalycinus forms a soil seed bank in the field, we investigated the seed density within the topsoil (upto a depth of 5 cm) of a coastal dune during summer and the seed germination ability of D. superbus var. longicalycinus. We found that a total of 194 seeds/0.52 m3 (186.5 seeds/m2) was produced during the last year or before at 26 sites. The Carex pumila community demonstrated the highest seed densities in the topsoil, followed by the Zoysia japonica, Liriope minor, and Juniperus conferta communities. The cumulative germination percentage of the seeds was 21.6% under constant temperature and darkness; however, it increased to 85.6% under alternating temperature and sunlight. It was thought that many seeds did not break dormancy through water absorption alone. Therefore, we concluded that seeds with germination ability remained in the topsoil after the spring season, forming a soil seed bank.
