Is photosynthesis related to concentrations of nitrogen and Rubisco in leaves of Australian native plants?
Charles R. Warren, Mark A. Adams and ZuLiang Chen Abstract The relationships among light-saturated photosynthesis and concentrations of nitrogen and ribulose-1,5- bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) in Australian native plants are poorly known, primarily due to the difficulty of extracting and analysing Rubisco from such species. Rubisco may be rapidly quantified in crude extracts of plant tissue by capillary electrophoresis (CE); however, the presence of phenolic compounds in many Australian native plants limits the use of these methods. The addition of insoluble polyvinylpolypyrrolidone (PVPP) during leaf extractions effectively removed phenols permitting quantitation of Rubisco. Relationships among maximum rates of photosynthesis and concentrations of nitrogen and Rubisco were then investigated in ten species native to Australia. Total nitrogen and the major pools of N in foliage varied greatly between species. Equally, within species N-partitioning was highly
