Friday, August 10, 2007

PS 72-27: Bromeliad germination: Is light an important factor in germination?

Miriam Toro-Rosario, Sonja Roque, Elvira Cuevas, and María F. Barberena. Center for Applied Tropical Ecology and Conservation (CATEC-UPR-Río Piedras)

Bromeliads are highly valuable herbs in the horticulture and economical fields. The recollection of basic information is crucial to establish and expand the data base related to rates and light availability dependence in germination stage. Our objective was to determine the germination rate in presenceand absenceof light for each species. We used seven species, and approximately 500 seeds/species.  For each species, we split half seeds to each of the treatments: light and no light, and placed 50 seeds/petri dish.  We counted germinated seeds three times per week for two months.  The no light seeds were exposed to sun light during counting.  We found that germination was highest with light than in no light.  Aechmea I had the highest germination in both treatments, suggesting that this exclusive epiphyte and ornamental species, has potential use in horticulture.  Guzmania monostachya and Tillandsia fasciculata didn't germinate in either treatment possibly due to low seed viability.  The germination peak varied among species but was within 3-4 weeks.  Among the remaining species, epiphyte/terrestrial bromeliads germinated similarly in both treatments, while exclusive terrestrial species only germinated in the light treatment.