title: Differential responses of tetrasporophytes and gametophytes of Mazzaella laminarioides (Gigartinales, Rhodophyta) under solar UV radiation.
abstract: The effects of solar UV radiation on mycosporine-like amino acids (MAAs), growth, photosynthetic pigments (Chl a, phycobiliproteins), soluble proteins (SP), and C and N content of Mazzaella laminarioides tetrasporophytes and gametophytes were investigated. Apical segments of tetrasporophytes and gametophytes were exposed to solar radiation under three treatments (PAR [P], PAR+UVA [PA], and PAR+UVA+UVB [PAB]) during 18 d in spring 2009, Punta Arenas, Chile. Samples were taken after 2, 6, 12, and 18 d of solar radiation exposure. Most of the parameters assessed on M. laminarioides were significantly influenced by the radiation treatment, and both gametophytes and tetrasporophytes seemed to respond differently when exposed to high UV radiation. The two main effects promoted by UV radiation were: (i) higher synthesis of MAAs in gametophytes than tetrasporophytes at 2 d, and (ii) a decrease in phycoerythrin, phycocyanin, and SPs, but an increase in MAA content in tetrasporophytes at 6 and 12 d of culture. Despite some changes that were observed in biochemical parameters in both tetrasporophytes and gametophytes of M. laminarioides when exposed to UVB radiation, these changes did not promote deleterious effects that might interfere with the growth in the long term (18 d). The tolerance and resistance of M. laminarioides to higher UV irradiance were expected, as this intertidal species is exposed to variation in solar radiation, especially during low tide.
authors.affiliation: Facultad de Ciencias, Universidad de Magallanes, Casilla 113-D, Punta Arenas, Chile.
authors.forename: Nelso P
authors.initials: NP
authors.lastname: Navarro
authors.affiliation: Departamento de Ecología, Facultad de Ciencias, Universidad de Málaga, Campus Universitario de Teatinos s/n, Málaga, 29071, España.
authors.forename: Félix L
authors.initials: FL
authors.lastname: Figueroa
authors.affiliation: Departamento de Ecología, Facultad de Ciencias, Universidad de Málaga, Campus Universitario de Teatinos s/n, Málaga, 29071, España.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Korbee
authors.affiliation: Facultad de Ciencias, Universidad de Magallanes, Casilla 113-D, Punta Arenas, Chile.
authors.forename: Andrés
authors.initials: A
authors.lastname: Mansilla
authors.affiliation: Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, Cidade Universitária, 05508-090, São Paulo, São Paulo, Brazil.
authors.forename: Estela M
authors.initials: EM
authors.lastname: Plastino
mesh_terms: D002677:Chile; D055993:Germ Cells, Plant / Q000254:growth & development / Q000528:radiation effects; D000461:Rhodophyta / Q000254:growth & development* / Q000528:radiation effects*; D014466:Ultraviolet Rays
keywords: Magellan Strait; biliproteins; life phases; mycosporine-like amino acids; seaweeds