Chloroplast feature of leaves of Arabidopsis plants grown at elevated or ambient CO2 in different generations.

The values given indicate means±SD from five plants. Number of starch grains per chloroplast profile was determined according to 300 chloroplasts. Area per starch grain was determined from 150 starch grains. The fully expanded rosette leaves were sampled at stage 5.0. Mean values were compared by t-test.*The seeds used in the reciprocal sowing experiments were from the fifteenth generation grown in ambient CO2 (SA) and elevated CO2 (SE).Abbreviations: AC: Ambient CO2; EC: Elevated CO2.