Elevated CO2 and nitrogen effects on crop defense phytohormones and pathogen susceptibility

Overview

Rising atmospheric CO2 levels are reshaping plant metabolism in ways that extend beyond photosynthesis. This research investigates how elevated CO2 combined with nitrogen fertilization weakens jasmonate-mediated defense signaling in economically important C3 crops, including spring wheat and canola. The work builds on prior findings in Arabidopsis and translates them to crop species, providing growers, breeders, and crop protection companies with actionable insight into how climate and nutrient management jointly influence plant immunity. Understanding these interactions is critical for forecasting pest and disease pressure, refining integrated pest management strategies, and guiding breeding programs aimed at maintaining crop resilience under future atmospheric conditions.

Technical specifications

Research scope and approach:

• Comparative analysis of monocot (spring wheat) and dicot (canola) C3 crop responses under ambient (450 ppm) and elevated (900 ppm) CO2
• Nitrogen treatments using ammonium nitrate at sub-optimal, standard, and supra-optimal rates (1/10x, 1x, 10x) to capture fertilization intensity effects
• Wound-induced time-course sampling at 0, 0.5, and 6 hours for carbon-to-nitrogen ratio, phytohormone profiling, and gene expression analyses
• Bioassays with economically relevant bacterial and fungal pathogens spanning different phytohormone defense pathways
• Caterpillar herbivore resistance assessments coupled with phytohormone and transcript measurements
• Evaluation of differential susceptibility to necrotrophic versus biotrophic pathogens under combined CO2 and nitrogen treatments

Key hypothesis areas:

• Elevated CO2 suppresses wound-induced jasmonate accumulation in nitrogen-fertilized C3 crops
• Reduced jasmonate signaling increases vulnerability to necrotrophic pathogens and chewing insects
• Enhanced nitrogen availability amplifies defense attenuation effects

Technology readiness level

The research is at an advanced hypothesis-validation stage. Prior laboratory work has already demonstrated attenuated jasmonate responses in nitrogen-fertilized Arabidopsis under elevated CO2. The proposed experiments extend these findings to crop species and incorporate pathogen and herbivore bioassays. Outputs will include phytohormone datasets, gene expression profiles, and resistance phenotypes that can inform crop modeling, breeding targets, and integrated pest management frameworks. The platform is positioned for sponsored research collaboration and co-development with agricultural industry partners seeking to anticipate and mitigate climate-driven shifts in crop pest and disease dynamics.