Pathway analysis of the transcriptome and metabolome of salt sensitive and tolerant poplar species reveals evolutionary adaption of stress tolerance mechanisms

Table 3 Photosynthesis, respiration and carbohydrates in P. euphratica and P. × canescens

Parameter	*P. euphratica*	P. × *canescens*
Net photosynthesis (μmol CO₂ m^-2s^-1)	2.97 ± 0.58***	4.79 ± 0.30
Transpiration (μmol H₂O m^-2s^-1)	0.79 ± 0.41(*)	1.91 ± 0.09
Dark respiration (μmol CO₂ m^-2s^-1)	1.43 ± 0.05***	0.34 ± 0.39
Glucose (μmol g^-1 FW)	9.80 ± 3.15***	4.43 ± 1.52
Fructose (μmol g^-1 FW)	0.43 ± 0.06*	0.38 ± 0.02

Photosynthesis and transpiration were determined at 150 μmol m^-2 s^-1 PAR, a temperature of 26°C and an air humidity of 60%. Dark respiration was measured for 5 min after keeping the plants in darkness for 30 minutes (n = 4, mean ± SD). Glucose and fructose content were determined in mature fully light exposed leaves (n = 5, mean ± SD). Significant differences are indicated by (*) for P ≤ 0.09, * for P ≤ 0.01 and *** for P ≤ 0.001.

ISSN: 1471-2229