Seed germination and seedling development of Halophila decipiens Ostenfeld (Hydrocharitaceae) from Panama

Abstract

Ligth plays a role in the seed germination and seedling development of Halophila decipiens Ostenfeld from Panama. Seeds remained ungerminated in the dark but began to germinate 3–7 days after transfer to lighted laboratory conditions. Seeds in light germinated in salinities ranging from 25 to 34% but remained ungerminated at 42%. Seed coats opened in light at 10% but embryos failed to develop after transfer to 35%. Seedlings floating in seawater developed variously, most to a 1-leaf stage, some to a 2-leaf stage and a few to a 3-leaf stage. In soil cultures at 100–125 μE m −2 s −1, 6 leaves were produced into a rosette before the emergence of a rhizome in the axil of the third leaf. In the soil cultures, the first bud on the rhizome developed 2 leaves and a single root. The development of the seedling into a 6-leaf rosette conformed to the pattern that was shown also in H. engelmannii Aschers. and may represent a generic pattern for seedlings of Halophila.