Spore germination of eight homosporous ferns in a temperature gradient


Por: Juárez-Orozco S., Orozco-Segovia A., Mendoza-Ruiz A., Pérez-García B.

Publicada: 1 jul 2013
Categoría: Plant Science

Resumen:
Temperature determines the germination percentage and germination rate of non-dormant fern spores and is known to be a crucial factor for breaking or inducing dormancy in seeds. The objective of this study was to determine the effect of optimal, supraoptimal and suboptimal temperatures on spore germination of eight species of terrestrial homosporous ferns. Spores were incubated for one month in a temperature gradient from 15 to 35 degrees C in either light or dark. Thereafter, the spores were transferred to 25 degrees C and incubated in the light. The optimal temperature for germination varied among species, and germination inhibition and possible secondary dormancy were induced at both suboptimal and supraoptimal temperatures. At 35 or 30 degrees C, with light, spores of most species did not germinate or exhibited low germination percentages, owing to thermoinhibition or possible thermodormancy. In the dark, the spores did not germinate at any of the temperatures tested. After the spores were transferred to the light at 25 degrees C, a high percentage of spore germination was observed. Incubation in the dark at different temperatures also promoted high germination or dormancy. Temperatures that promoted germination might be related to the season that the different species germinate rather than their habitat, as a number of species within the same habitat had different optimum temperature requirements. Differences in temperature requirements may help to form a soil spore bank. It is necessary to determine whether secondary dormancy was induced by supraoptimal and suboptimal temperatures to further understand spore germination and colonisation in the field. (C) 2013 SAAB. Published by Elsevier B.V. All rights reserved.

Filiaciones:
Juárez-Orozco S.:
 Univ Nacl Autonoma Mexico, Fac Ciencias, Dept Ecol & Recursos Nat, Lab Proc & Interacc Ecol, Mexico City 04510, DF, Mexico

Orozco-Segovia A.:
 Univ Nacl Autonoma Mexico, Dept Ecol Func, Inst Ecol, Mexico City 04510, DF, Mexico

Mendoza-Ruiz A.:
 Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Biología, San Rafael Atlixco 186, C.P. 09340 México, D.F., Mexico

Pérez-García B.:
 Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Biología, San Rafael Atlixco 186, C.P. 09340 México, D.F., Mexico
ISSN: 02546299
Editorial
ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, Países Bajos
Tipo de documento: Article
Volumen: 87 Número:
Páginas: 112-117
WOS Id: 000321163500017
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