The photosynthetic acclimation of Lolium perenne growing in a free-air CO₂ enrichment (FACE) system

THE PHOTOSYNTHETIC RESPONSE OF THE PERENNIAL RYEGRASS (LOLIUM PERENNE) IN ITS FIFTH YEAR OF FREE-AIR CO{sub 2} ENRICHMENT (FACE) AT ESCHIKON, SWITZERLAND

“…The results of the diurnal measurements for the 1992 stands of L. perenne revealed a clear and consistent increase in leaf A and a consistent decrease in leaf~values for all the plants grown and measured at high [COZ].This corresponds to studies into L. perenne stands conducted at the Swiss-FACE facility in previous years (Bryant 1994;Nosberger et. al.…”

“…The initial slope of the dependence of C02 assimilation rate Whilst down regt.dation of the photosynthetic apparatus observed in Iaboratog studies could be a result of the use of small pots restricting root growth (Arp 1991), acclimation has also been obsemed in field studies (Bryant 1994). However, down regulation at an elevated [C02] is not always the case, for example a study by Arp and Drake (1991) into the long term effects of elevated COZ on a community of Sciquus ohzeyi showed no loss of photosynthetic capacity.…”