Physiological Responses of Plants to Combined Drought and Heat under Elevated CO2

Abstract

Anthropogenic activities over the last century have caused rapid changes in environmental conditions through increasing CO2 emissions in the atmosphere that contribute to global warming. Moreover, the increased global average temperature is linked with changes in the precipitation rate and distribution, resulting in a negative impact on crop health and productivity. Plants in nature often experience combined stresses; therefore, they have developed adaptive mechanisms to cope with fluctuating environmental conditions. Thus, investigating plant responses under unfavorable environmental conditions will provide a better understanding of how crops can adapt and thereby assist in selecting climate-resilient crops that can withstand climate variability. This review highlights the main adaptive physiological and biochemical responses of crops grown under elevated CO2 (eCO2) and exposed to combined abiotic stresses (drought and heat). Moreover, the mitigation and limitation impact of elevated CO2 on plants under the combination of stress is discussed.