Intraspecific variation in the response of Arabidopsis thaliana lines to elevated atmospheric CO2

Since a study of the intraspecific variation in the response to elevated CO 2 of different genetic lines of one species might reveal the parameters ess ential for the response of a species to elevated CO2, thirteen lines of Ara bidopsis thaliana L. were exposed to elevated CO2 (700 mul l(-1)). All line s increased shoot biomass, leaf area and starch content and most lines decr eased specific leaf area (SLA) upon exposure to elevated CO2. The lines dif fered in the magnitude of their response to elevated CO2 (ratio 700/350), v iz. 1.09 to 1.68 for the increase in shoot biomass, 1.00 to 1.44 for the in crease in leaf area, 1.40 to 1.71 for the increase in starch content and 1. 02 to 0.84 for the change in SLA. Both soluble sugar and structural dry mat ter content were hardly affected by elevated CO2. The changes in the variou s parameters are discussed in relation to the life strategy of Arabidopsis thaliana L.