INVESTIGADORES
PARODI Elisa Rosalia
artículos
Título:
The heteromorphic phases of Leathesia marina (Ectocarpales, Ochrophyta) over time from northern Patagonia, Argentina
Autor/es:
POZA, A.M.; GAUNA, M.C.; ESCOBAR, J.; PARODI, E.R.
Revista:
PHYCOLOGIA
Editorial:
INT PHYCOLOGICAL SOC
Referencias:
Lugar: Lawrence; Año: 2017 p. 579 - 589
ISSN:
0031-8884
Resumen:
The emergence and evolution of the heteromorphic life history in algae has been 26 considered as a response to the selective pressures of changing environments. The brown alga 27 Leathesia marina has a typical heteromorphic life history, alternating between microscopic 28 branched filaments (gametophytic phase) and a macroscopic erect stage (sporophytic phase). The 29 first aim of this study was to describe vegetative and reproductive morphologies of sporophytes 30 (macrothalli and diploid phase) of L. marina and their relationship with environmental factors in 31 an annual cycle. The second aim was to report the discovery of gametophytes (microthalli and 32 haploid phase) in the natural environment on northern Patagonian coasts, and to describe their 33 morphology, abundance and reproductive output. The macroscopic phase was observed over 34 eight months, from September to April during the warm season. The microscopic phase was 35 observed in two periods, March-April and September-October. A temporal overlap was observed 36 between the microscopic and macroscopic phases. The population of macrothalli had a type III 37 survivorship curve. The cover, density and size of macrothalli were associated with warmer 38 months, but the abundance of microthalli and reproductive output of both phases were higher in 39 temperate periods. Demographic parameters, including mortality rate, survivorship, reproductive 40 output, and the morphological characteristics of L. marina are used to evaluate the adaptation of 41 this species to a changing environment, typical of the temperate coasts of northern Patagonia in Argentina.