Assessment of photosynthesis and yield loss of winter wheat under ground-level ozone exposure

In recent years, ground-level ozone (O3) pollution in China has shown an upward trend along with the decline of PM2.5. O3 not only affects human health, but also affects the photosynthesis of crops, thereby reducing crop yields. The current research on O3 -induced crop yield losses is mainly based on statistical models, and the mechanism research of O3 impacts on crops is still relatively scarce. This study simulated the photosynthesis and yield loss of winter wheat under different levels of O3 concentration. The results showed that the photosynthetic loss rate of winter wheat under 150 nLmiddotL-1, 100 nLmiddotL-1, and 50 nLmiddotL-1O3 treatments were 72%, 36%, and 6%, respectively, under high sensitivity effect, and they were 13%, 6%, and 1%, respectively, under low sensitivity effect. The photosynthetic loss rate of the control group (CK, ambient air) under these two sensitivity effects were 10% and 2%, respectively. The calculated cumulative stomatal O3 absorption flux (PODY) of winter wheat had the highest correlation with the relative yields when the threshold Y is set to be 7 nmolmiddot (m2middots)-1.If POD7 is increased by 1 mmolmiddotO3middotm-2, the yield of winter wheat will decrease by 6.5%. Our simulation methods and results can provide a scientific basis for formulating countermeasures against O3 damage to crops.(c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).