Nitrogen-Centric Molecular Mechanisms in Crop Plants Under Elevated CO₂: Interactions, Responses, and Implications

Area of Science:

• Plant Physiology
• Agricultural Science
• Biochemistry

Background:

• Rising atmospheric carbon dioxide (CO2) alters plant growth environments, impacting crop physiology and productivity.
• Elevated CO2 can enhance photosynthesis and biomass but negatively affects nitrogen (N) metabolism, reducing crop nutritional quality and yield.

Purpose of the Study:

• To review molecular processes regulating nitrogen responses in crops under elevated CO2.
• To highlight differences in plant responses (legume vs. non-legume, C3 vs. C4).
• To outline future crop improvement strategies for climate resilience.

Main Methods:

• Review of molecular mechanisms controlling N assimilation, distribution, and remobilization.
• Analysis of altered gene expression and enzyme activities in N-regulated protein machineries.
• Examination of systemic plant responses to C-N signaling.

Main Results:

• Elevated CO2 alters expression and activity of key N-metabolism proteins due to reduced N concentration.
• Complex plant responses, including photosynthesis adaptation and altered nutrient profiles, are observed.
• Differences exist in C3 vs. C4 and legume vs. non-legume responses to high CO2.

Conclusions:

• Holistic analysis of N metabolism regulatory networks is crucial for high CO2 environments.
• Crop improvement strategies should focus on enhancing N assimilation resilience and C-N stoichiometry.
• Optimizing N transporters and maintaining C-N balance are key for crop performance and nutrition under climate change.