Studies on the Seed Biology of 100 Native Species of Trees in a Seasonal Moist Tropical Forest, Panama, Central America

Studies on the Seed Biology of 100 Native Species of Trees in a Seasonal Moist Tropical Forest, Panama, Central America

Background

Since 1998, the Panama Canal Watershed has experienced a decline in forest cover. The watershed ensures a functioning canal, thus there has been a significant investment in resources to reforest and restore the region. While these projects have focused primarily on native species, there has been issues with seed-handling. 

Research Goals & Methods

This study seeks to present, at a regional scale, information about various aspects of the whole-seed biology of 100 tree species native to the PCW in order to inform future restoration and reforestation initiatives. Seeds of 32, 29, and 33 species were dispersed during the dry (DS, January–March), early rainy (ERS, April–July), and late rainy (LRS, August–December) seasons, respectively. Information was colllected for each species, including fruit collection/seed cleaning system, time of fruiting, seed mass, seed moisture content, dormancy/germination characteristics, and/or longevity in storage. 

Conclusions & Takeaways

The study found that germination for untreated seeds was above 50% for 46 species. 49 of the 94 fresh seeds that germinated were nondormant and 45 were dormant. Twelve species had a median length of germination time, of which those dispersed in the LRS was higher than that of those dispersed in the ERS or DS. Forty-eight species had uniform germination. Seed longevity ranged from 0.5 to 36 months, and long-lived (L-L) seeds tended to be larger than short-lived (S-L) or very short-lived (very S-L) ones, but not significantly so. Moisture content increased significantly from L-L to very S-L seeds. The highest proportion of L-L seeds was dispersed in the DS and the lowest in the LRS. Overall, the authors recommend that to improve nursery production, germination pretreatments should be determined for species that germinate to low percentages and/or at low rates without pretreatment, thus facilitating use of space and scheduling of seedling production.

Reference: 

Sautu A, Baskin JM, Baskin CC, Condit R. Studies on the seed biology of 100 native species of trees in a seasonal moist tropical forest, Panama, Central America. Forest Ecology and Management. 2006;234:245–263. doi:10.1016/j.foreco.2006.07.006.

Affiliation: 

  • Department of Biology, University of Kentucky, Lexington, KY, USA
  • Smithsonian Tropical Research Institute, Panama City, Panama
  • Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY, USA