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Poster: Epidemiology: Climate Change


Effects of vernalization on the differential ozone response of two winter wheat genotypes.
A. MASHAHEET (1), D. Marshall (2), K. Burkey (2) (1) North Carolina State University, U.S.A.; (2) USDA-ARS, North Carolina State University, U.S.A.

Elevated ground-level ozone, associated with climate change is a limiting factor to wheat production. Evaluating winter wheat for ozone responses could be accomplished more rapidly at the seedling stage using unvernalized seedlings. However, there is no information available on the effects of vernalization on the expression of ozone injury responses, and the association of these responses to yield losses at adult plant stage. Twenty five winter wheat genotypes (including historical and recent varieties and breeding lines) were evaluated for ozone tolerance (at CF, 50, 70, 90 and 110 ppbv, 8hrs/day for 1 week), and two lines with differential ozone response were selected, Coker-9553 (O3-sensitive) and MD01W28-08-11 (O3-tolerant). These two genotypes were used to study the effects of vernalization on the differential ozone response, and the validity of results if unvernalized seedlings are used. Foliar Injury results at the seedling stage showed that vernalization has no significant effect on the differential ozone responses, and the two genotypes could be separated using vernalized or non-vernalized plant material. The differential response obtained at the seedling stage was validated at the adult-plant stage. Yield losses under elevated ozone treatments in open-top chambers were associated with increased foliar injury observed at the seedling stage.