Abstract Detail

Pteridology

Flores-Galván, Catalina [1], Mata-Rosas, Martín [2], Márquez-Guzmán, Judith [3], Watkins, James [4], Mehltreter, Klaus [5].

Impact of Calcium concentration on spore germination of ferns with different soil preferences.

Ferns are the second most diverse group of vascular plants after angiosperms and occur in diverse habitats from rainforest canopies and rocky outcrops in dry environments to aquatic ecosystems and beyond. With approximately 10,578 species, Mexico makes up nearly 9% of the total global species richness and is the country with the highest diversity of xerophytic species. Despite the efforts made to understand the functional ecology of ferns over the last two decades, few studies have focused on epipetric species that grow on rocks with different calcium (limestone vs. volcanic) or aluminum content. Therefore, we studied fern spore germination of eight species of ferns with different substrate specificity in vitro: Argyrochosma formosa, Llavea cordifolia (limestone), Anemia phyllitidis, Hemionitis palmata, Woodsia mollis (terrestrial or epipetric), Myriopteris aurea, Pellaea cordifolia, and P. ternifolia (volcanic). Spores were sown on autoclaved Parker-Thompson media (pH 5.8 ± 0.03) with three different calcium concentrations (2, 20 and 200 ppm; n=12 per species and treatment) and observed for 3 months, all cultures were maintained at 25° C with 16 h artificial photoperiod. After 8 weeks, A. formosa, H. palmata, M. aurea, and P. ternifolia reached 100% germination in all treatments and A. formosa and M. aurea presented already young sporophytes. After 12 weeks, L. cordifolia reached its maximum germination at the highest Ca concentration, whereas germination of P. cordifolia ad W. mollis peaked at lower Ca concentrations. The results for the latter three species were in accordance to our expectations, because L. cordifolia is a limestone species, whereas P. cordifolia and W. mollis grow preferably on volcanic or igneous substrates. Our preliminary findings show the importance of abiotic factors such as Ca content to fern spore germination. Future research aims to combine different Ca concentrations along a pH gradient to gain a better understanding of the interaction between soil nutrient concentrations and nutrient availability at different pH levels.

1 - Instituto De Ecología, A. C., Ecología Funcional, Carretera Antigua A Coatepec 351 Colonia: El Haya, Xalapa, VER, 91073, Mexico
2 - Instituto de Ecología, A. C., Red de Manejo Biotecnológico de Recursos, Carretera Antigua A Coatepec 351 Colonia El Haya, Xalapa, VER, 91073, Mexico
3 - Facultad de Ciencias, Universidad Nacional Autónoma de México, Departamento de Biología Comparada, Av. Universidad 3000, Circuito Exterior s/n Alcaldía Coyoacán, Ciudad Universitaria, Ciudad de México, CDMX, 04510, Mexico
4 - Colgate University, Department Of Biology, 13 Oak Drive, Hamilton, NY, 13346, United States
5 - Instituto de Ecología, A. C., Red de Ecología Funcional, Carretera Antigua A Coatepec 351 Colonia El Haya, Xalapa, VER, 91073, Mexico

Keywords:
in-vitro germination
Ferns
limestone
volcanic/igneous
gametophytes
sporophytes.

Presentation Type: Oral Paper
Number: PTR2004
Abstract ID:944
Candidate for Awards:None