Abstract

Bald cypress has been retreating in the estuary ecosystem of the Loxahatchee River Watershed in southeastern Florida because of the negative impacts of anthropogenic activities. Seed germination of bald cypress is an important means to increase the arbor population in the vegetation community and accelerate restoration of the wetland ecosystem. The objective of this research was to find an effective method to enhance seed germination of bald cypress, an ecologically and economically important tree species. Bald cypress seeds were hand collected under mature bald cypress trees in southeastern Florida, and kept under refrigeration at 4^oC prior to the commencement of the study. The seeds were chemically treated in either 1% NaOH, 95% ethyl alcohol, 0.03 to 0.3% H₂O₂, or 1% HCl, or mechanically cut into two halves, or heated on a burner for 3.0 s. After treatment, all of the seeds were sown in Park's seed-starting trays with 72 Cellswith Pro Mix BX growth medium. The results showed that soaking the seeds in a 1% NaOH solution for 5 min and then in H₂O for 24 h had the best germination rate of approximately 50%. However, heating the seeds on a gas burner was the least effective, resulting in almost no germination. Unlike the results seen in other species, H₂O₂ did not enhance germination in the seeds. Therefore, 1% NaOH was shown to be the best treatment because it could neutralize the acidity of the seed resin. Our study has verified that acidity was the chief limitation for germination of the seeds.

Key words: Taxodium distichum, germination enhancement, acidity of seed resin, germination rate.