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Title: Understanding and improving global crop response to ozone pollution
Summary

Concentrations of ground‐level ozone ([O3]) over much of the Earth's land surface have more than doubled since pre‐industrial times. The air pollutant is highly variable over time and space, which makes it difficult to assess the average agronomic and economic impacts of the pollutant as well as to breed crops for O3tolerance. Recent modeling efforts have improved quantitative understanding of the effects of current and future [O3] on global crop productivity, and experimental advances have improved understanding of the cellular O3sensing, signaling and response mechanisms. This work provides the fundamental background and justification for breeding and biotechnological approaches for improving O3tolerance in crops. There is considerable within‐species variation in O3tolerance in crops, which has been used to create mapping populations for screening. Quantitative trait loci (QTL) for O3tolerance have been identified in model and crop species, and although none has been cloned to date, transcript profiling experiments have identified candidate genes associated withQTL. Biotechnological strategies for improving O3tolerance are also being tested, although there is considerable research to be done before O3‐tolerant germplasm is available to growers for most crops. Strategies to improve O3tolerance in crops have been hampered by the lack of translation of laboratory experiments to the field, and the lack of correlation between visual leaf‐level O3damage and yield loss to O3stress. Future efforts to screen mapping populations in the field and to identify more promising phenotypes for O3tolerance are needed.

 
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NSF-PAR ID:
10037343
Author(s) / Creator(s):
 
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
90
Issue:
5
ISSN:
0960-7412
Page Range / eLocation ID:
p. 886-897
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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