Effect of elevated temperature and CO2 on growth of two early-maturing potato (Solanum tuberosum L.) varieties

Climate change will significantly reduce potato yields across the world and have a profound impact on food security. However, the effects of changing climatic conditions on various traits of early-maturing potatoes at their different stages of growth are not clear. Therefore, 19 plant traits were investigated across the entire growth period of two major early-maturing potato varieties: Favorita and Zhongshu 5. These were grown in a temperature/CO₂-controlled walk-in chamber under four treatments that simulated the changes predicted in these two climate factors by 2100: Control (ambient temperature 21 ​°C; ambient CO₂ 400 ​μmol ​mol⁻¹), eT (elevated temperature 24 ​°C; ambient CO₂ 400 ​μmol ​mol⁻¹), eCO₂ (ambient temperature, 21 ​°C; elevated CO₂ 800 ​μmol ​mol⁻¹), and eTeCO₂ (elevated temperature 24 ​°C; elevated CO₂ 800 ​μmol ​mol⁻¹). Elevating ambient temperature by 3 ​°C (eT), elevating CO₂ concentration to 800 ​μmol ​mol⁻¹ (eCO₂), and a combination of both treatments (eTeCO₂) brought forward potato tuber initiation by approximately 10 days. eT treatment reduced the yield of Favorita by 83 ​% and Zhongshu 5 by 52 ​%, but simultaneously elevating the CO₂ concentration (eTeCO₂) alleviated the negative effects of higher temperature on plant morphology and biomass. Favorita exhibited greater stability than Zhongshu 5 under all treatment conditions. These findings will guide the development, cultivation, and research of climate-resilient potatoes as an adaptation to climate change to strengthen food security.