Stomata are very conserved structures in plants, which allows and control the
gas exchange. This ecophysiological fact appears to be critical in the ecology
and adaptation of plants to environment. Plant individuals can, among other
issues, adjust size and density of the stomata to adapt themselves to hydric,
thermic and light regimes. In turn, this led to the reduction of transpiration and
control of water losses, which is crucial in areas with Mediterranean climate. The
fern Osmunda regalis has populations in both biogeographical regions of the
Iberian Peninsula (Eurosiberian and Mediterranean regions), but when locations
are highly continental the populations are scarce and isolated. The objective of
this study is to characterize the stomatal morphological traits in both regions, to
detect possible adaptations in individuals occurring in Mediterranean locations.
26 individuals of 17 different populations were sampled. Applying microscopic
techniques, 4447 observations of length and width, and 234 of density and PCI
were done. The sampling spots were characterized by two bioclimatic indices of
Emberger and Gorzynski, and also mean maximum and minimum temperature
values were obtained. All the information was included in a dataset that was
statistically analyzed with the software SPSS. Our results show that Osmunda
regalis fronds have higher PCI and density values in the Eurosiberian region,
as expected. Gorczynski continentality index (K), and the mean maximum and
minimum annual temperatures influences over stomatal traits. This is clearly
informing that in the Mediterranean region, the temperature is an important
factor that triggers stomatal adaptations of O. regalis to continental locations with
higher levels of environmental stress. On the contrary, Emberger pluviometric
index (Q) seems to be less explicative by its own. Perhaps this is related with
the habitat of O. regalis in soils with high freatic level, fact which could...
Buscar en Dimension