Table 2. Stomatal conductance, transpiration rate and photosynthetic rate of leaves of Arabidopsis plants grown at elevated or ambient CO₂ in different generations.

Photosynthetic features		Stomatal conductance (mmol m−2 s−1)		decrease	Transpiration rate (mmol m−2 s−1)		decrease	Photosynthetic rate (µmol m−2 s−1)		increase
Treatment		AC	EC		AC	EC		AC	EC
Generation	1	385.6±23.2a	220.4±14.0b	42.8%	8.16±0.41a	5.18±0.24b	36.5%	14.1±1.2a	16.3±1.4b	15.6%
	8	410.4±25.5a	239.4±15.6b	41.7%	8.32±0.40a	5.46±0.25b	34.4%	14.8±1.5a	17.2±1.3b	16.2%
	15	377.8±21.6a	221.6±13.9b	41.3%	7.79±0.39a	5.15±0.21b	33.9%	13.5±1.4a	15.8±1.5b	17.0%
	SA*	382.0±20.4a	227.8±13.3b	40.4%	7.91±0.45a	5.34±0.28b	32.5%	13.9±1.4a	16.6±1.3	19.4%
	SE*	406.2±22.5a	230.4±16.1b	43.3%	8.05±0.36a	5.38±0.31b	33.2%	14.4±1.6a	16.9±1.7b	17.4%
P-value		0.061–0.801	0.078–0.895	/	0.067–0.650	0.067–0.838	/	0.204–0.813	0.162–0.808	/
Average		392.4	227.9	41.9%	8.05	5.30	34.1%	14.1	16.6	17.1%

The values given indicate means±SD from five plants. Three fully expanded rosette leaves at stage 5.0 were sampled from each of five plants were analyzed for stomatal conductance, transpiration rate and photosynthetic rate. 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.