Nielsen, Hanne Dalsgaard, Brownlee, Colin, Coelho, Susana M and Brown, Murray T (2003) Inter-population differences in inherited copper tolerance involve photosynthetic adaptation and exclusion mechanisms in Fucus serratus. New Phytologist, 160 (1). pp. 157-165. ISSN 14698137

Abstract/Description

• A comparative study of copper (Cu) toxicity and tolerance in three populations of Fucus serratus was conducted by examining Cu2+ effects on various physiological parameters.

• Chlorophyll fluorescence, oxygen evolution, copper content, and relative growth rate of embryos and adults were measured on Cu2+-exposed material.

• Algae naturally exposed to elevated total Cu concentration (CuT), were more Cu2+ resistant than those from clean sites, as indicated by higher embryo and adult growth rates and lower copper contents. The Cu2+ tolerance of F. serratus is at least partly inherited and relies partly on metal exclusion.

• There were inhibitory effects of Cu2+ on oxygen exchange rates in both tolerant and non-tolerant algae. By contrast to sensitive algae, the maximum efficiency of photosystem II (Fv/Fm), maximum fluorescence (Fm) and zero fluorescence (Fo) of resistant algae were unaffected by Cu2+, whereas decreased quantum yield (ΦPSII) and increased nonphotochemical quenching (NPQ) were most pronounced in resistant algae. Inhibitory effects of Cu2+ on ΦPSII may result in the excitation energy being dissipated through xanthophyll-dependent quenching mechanisms in tolerant algae. In nontolerant algae, lower energy dissipation may result in chlorophyll degradation.

Actions (login required)