Carbon dioxide interactions with irradiance and temperature in potatoes

Area of Science:

• Plant Physiology
• Agricultural Science
• Environmental Science

Background:

• Understanding the impact of environmental factors on crop yield is crucial for food security.
• Carbon dioxide (CO2) concentration, irradiance, and temperature are key environmental variables influencing plant growth.

Purpose of the Study:

• To investigate the interactive effects of elevated CO2 with irradiance and temperature on potato (Solanum tuberosum) growth.
• To determine optimal environmental conditions for maximizing potato tuber yield.

Main Methods:

• Two controlled environment studies were conducted using three potato cultivars.
• Study 1: Examined CO2 (ambient vs. 1000 µmol mol⁻¹) interaction with photosynthetic photon flux (PPF) and photoperiod.
• Study 2: Assessed CO2 (500–2000 µmol mol⁻¹) interaction with temperature (16°C vs. 20°C) under a 12-hour photoperiod.

Main Results:

• Elevated CO2 significantly increased tuber and total dry weights, with diminishing returns at higher PPF and longer photoperiods.
• Higher temperatures (20°C) generally promoted greater plant growth than lower temperatures (16°C) across all CO2 levels.
• Optimal tuber yield was observed at a PPF of 34 mol m⁻² d⁻¹, 20°C, and CO2 concentrations of 1000–2000 µmol mol⁻¹.

Conclusions:

• Potato growth is enhanced by elevated CO2, but this response is modulated by light and temperature.
• Specific environmental parameters are critical for optimizing potato production under future atmospheric conditions.
• Carbohydrate accumulation in leaves at 16°C under elevated CO2 may limit plant response.