Effects of the bisulphite ion on growth and photosynthesis in Sphagnum cuspidatum Hoffm.

Abstract

S U M M A R ySboots of Sphagnum cuspidatum Hoffm. were collected from two sites: one, a relatively unpolluted site in N. Wales, remote from pollution sources and tbe other, a grossly polluted site in the South Pennines.* Material Irom both sites vvas grown in the laboratory and exposed to artificial rainwater solution with and witbout bisulpbite (HSO,, ) amendment (01 mM). Effects of exposure to HSO,, for up to 21 days on growth, photosynthesis, •^blorophyll a fluorescence and chlorophyll concentrations were studied in the two Spbagiium populations.Application of HSO., produced significantly less than maximum growtb in Spliagnum from botb sites. Tbis effect was far greater, however, in tbe material from the unpolluted Welsb site.Photosynthesis in the Welsh material treated with HSO.j" decreased steadily with time; after 21 days of *^xposure, pbotosyntbetic oxygen evolution bad ceased. Tbis decrease was accon-ipanied by a decrease in fluorescence c^uencbing (as [(P -T)/P|), suggesting a gradual loss of water-splitting activity.In contrast, HSO,, initially stimulated pbotosyntbesis in Sphagnum from the polluted site. Chlorophyll Concentration was decreased in Sphagnum from both sites in the presence of HSO., .Possible mecbanisms of tolerance to HSO,, are discussed.

Photosynthetic performance in Sphagnum transplanted along a latitudinal nitrogen deposition gradient

“…Several papers have demonstrated a correlation between photosynthetic rate and maximum eYciency of PSII in mosses (Murray et al 1993;Potter et al 1996), but so far chlorophyll Xuorescence has predominantly been used in experiments exploring more severe stress, such as desiccation studies (Baxter et al 1989;Csintalan et al 1999;Deltoro et al 1998;Potter et al 1996). In our study, the maximum eYciency of PSII explained 36 and 52% of the photosynthetic rate in S. fuscum and S. balticum, respectively.…”

Temperature Dependency of Photosynthesis of <i>Sphagnum</i> spp. Distributed in the Warm-Temperate and the Cool-Temperate Mires of Japan

“…Bisulphite ( 3 ) in the atmospheric deposition has an extremely inhibiting effect on Sphagnum photosynthesis [17][18][19], and 5.0 mM of 3 has a completely fatal effect on Sphagnum. Iron deposition accompanying bisulphite deposition from the atmosphere decreases the effect of bisulphite on Sphagnum, and thus plants growing in polluted areas have higher tolerance capability for atmospheric pollution [20].…”

The relationship between extracellular metal accumulation and bisulphite tolerance in Sphagnum cuspidatum Hoffm.

“…This resulted in visible signs of bleaching injury, perturbation of photosynthesis and growth processes (Baxter, et al, 1989). The increase in rate of oxidation promoted by the S. Pennine material had two effects: firstly preventing damage to the plant by HSO.|" by its rapid removal from solution, and secondly effecting an increased supply of SO/" to the plants.…”