New insight into photosynthetic acclimation to elevated CO2: The role of leaf nitrogen and ribulose-1,5-bisphosphate carboxylase/oxygenase content in rice leaves

Abstract

We tested the hypothesis that photosynthetic (A) acclimation to elevated CO2 partial pressure (p[CO2]) is associated with the inhibition of protein synthesis, inhibition of nitrogen (N) partitioning into the leaf blade and/or accelerated leaf senescence in rice (Oryza sativa L. cv. Notohikari). Plants were grown for 70 days hydroponically in artificially illuminated growth chambers at a p[CO2] of either 39 or 100Pa at N 2mM. Leaf A, Vc.max, Jmax, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco, E.C.4.1.1.39), mRNA for associated genes rbcS and rbcL, total N and carbohydrate concentrations in leaves at different positions in the canopy were measured. Spatial allocation of N and Rubis..