Ozone tolerant maize hybrids maintain Rubisco content and activity during long-term exposure in the field

Authors: CHOQUETTE, N - University Of Illinois; Ainsworth, Elizabeth - Lisa; BEZODIS, W - Oxford University; CAVANAGH, A - University Of Illinois

Submitted to: Plant Cell and Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/21/2020
Publication Date: 8/24/2020
Citation: Choquette, N.E., Ainsworth, E.A., Bezodis, W., Cavanagh, A.P. 2020. Ozone tolerant maize hybrids maintain Rubisco content and activity during long-term exposure in the field. Plant Cell and Environment. 43(12):3033-3047. https://doi.org/10.1111/pce.13876.
DOI: https://doi.org/10.1111/pce.13876

Interpretive Summary: Ozone pollution damages maize yields as much as nutrient deficiency, heat, and aridity stress. Therefore, understanding the how maize responds to ozone pollution and identifying traits that are predictive of ozone tolerance is important. In this study, we examined the physiological, biochemical and yield responses of six maize hybrids to elevated ozone in the field. Elevated ozone stress reduced photosynthetic capacity, but did not alter stomatal limitation of photosynthesis or antioxidant capacity of maize. Rather, tolerance to ozone stress in the hybrid B73 x Mo17 was correlated with maintenance of leaf N content. This work identified a tolerant maize line, and the physiological mechanism of tolerance.

Technical Abstract: Ozone pollution is a damaging air pollutant that reduces maize yields equivalently to nutrient deficiency, heat, and aridity stress. Therefore, understanding the physiological and biochemical responses of maize to ozone pollution and identifying traits predictive of ozone tolerance is important. In this study, we examined the physiological, biochemical and yield responses of six maize hybrids to elevated ozone in the field using Free Air Ozone Enrichment. Elevated ozone stress reduced photosynthetic capacity, in vivo and in vitro, decreasing Rubisco content, but not activation state. Contrary to our hypotheses, variation in maize hybrid responses to ozone was not associated with stomatal limitation or antioxidant capacity of maize. Rather, tolerance to ozone stress in the hybrid B73 x Mo17 was correlated with maintenance of leaf N content.