Plants increase CO2 uptake by assimilating nitrogen via the photorespiratory pathway

Research output: Contribution to journalArticlepeer-review

Authors

Colleges, School and Institutes

External organisations

  • Australian National University
  • University of Toronto

Abstract

Photorespiration is a major bioengineering target for increasing crop yields as it is often considered a wasteful process. Photorespiratory metabolism is integrated into leaf metabolism and thus may have certain benefits. Here, we show that plants can increase their rate of photosynthetic CO2 uptake when assimilating nitrogen de novo via the photorespiratory pathway by fixing carbon as amino acids in addition to carbohydrates. Plants fed NO3 - had higher rates of CO2 assimilation under photorespiratory than low-photorespiratory conditions, while plants lacking NO3 - nutrition exhibited lower stimulation of CO2 uptake. We modified the widely used Farquhar, von Caemmerer and Berry photosynthesis model to include the carbon and electron requirements for nitrogen assimilation via the photorespiratory pathway. Our modified model improves predictions of photosynthetic CO2 uptake and of rates of photosynthetic electron transport. The results highlight how photorespiration can improve photosynthetic performance despite reducing the efficiency of Rubisco carboxylation.

Details

Original languageEnglish
Pages (from-to)46-54
Number of pages9
JournalNature Plants
Volume4
Issue number1
Early online date11 Dec 2017
Publication statusPublished - Jan 2018

ASJC Scopus subject areas