Shortcutting Photorespiration Protects Potato Photosynthesis and Tuber Yield Against Heatwave Stress

Area of Science:

• Plant Biotechnology
• Crop Science
• Metabolic Engineering

Background:

• Global warming is increasing the frequency and intensity of heatwaves, posing a significant threat to agricultural productivity.
• Enhancing photosynthetic efficiency and stress tolerance in crops is crucial for maintaining global food security.
• Genetic modification offers a powerful tool to improve crop performance under adverse environmental conditions.

Purpose of the Study:

• To evaluate the impact of a synthetic glycolate metabolic pathway (AP3) on potato tuber biomass and quality.
• To assess the effect of this pathway on photosynthetic capacity and heatwave tolerance in potato plants.
• To determine the potential of AP3 pathway as a strategy for improving crop yields in the context of climate change.

Main Methods:

• Expression of a synthetic chloroplast-localized glycolate metabolic pathway (AP3) in potato plants.
• Measurement of tuber biomass and quality parameters over two growing seasons.
• Assessment of carbon assimilation rates, Vcmax, and Jmax under varying temperature conditions, including natural heatwaves.
• Comparison of transformed plants with untransformed controls.

Main Results:

• Transformed potato plants exhibited enhanced tuber biomass compared to controls.
• No negative impact on tuber quality was observed in the transformed plants.
• During heatwaves, transformed plants showed significantly higher carbon assimilation, Vcmax (up to 23%), and Jmax (up to 13%) during tuber bulking.
• The yield benefits and enhanced photosynthetic capacity were more pronounced following early-season heatwaves.

Conclusions:

• The AP3 synthetic metabolic pathway effectively enhances potato tuber yield and biomass.
• AP3 pathway confers improved photosynthetic capacity and heatwave tolerance to potato plants.
• This pathway represents a promising strategy for increasing crop resilience and yield stability in the face of climate change-induced heat stress.