The seed reserve of Halophila decipiens Ostenfeld (Hydrocharitaceae) in Panama

Abstract

Dormant seeds of Halophila decipiens Ostenfeld were present in sediment on the Caribbean coast of Panama. In the upper 3 cm of sediment, 13 500 seeds m −2 were detected. After removal from the sediment, seeds began to germinate in 2–3 days and had 86% germination after 9 days under lighted laboratory conditions. Seeds removed from fruits still attached to rhizomes remained ungerminated in the dark at 24°C, but showed 64% germination after 9 days in light. The natural release of seeds into the sediment from buried fruits, containing a mean of 36.8 seeds, probably contributes to the seed reserve. Upon disturbance of the sediments, germination from the buried reserve allows colonization of newly-exposed sites and maintenance of the local population of H. decipiens.