Title: Ozone's suffocating effect on soybean physiology, growth and yield Author
Submitted to: Plant Biology Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: May 29, 2013
Publication Date: N/A
Technical Abstract: Tropospheric ozone (O3) is damaging air pollutant that is currently costing U.S. farmers hundreds of millions of dollars in yield losses each year. The detrimental effect of O3 on soybean production has been recognized over the past 30 to 40 years, yet there has been little effort to improve soybean response to O3 through breeding or biotechnology. Free Air Concentration Enrichment (FACE) allows the growth of soybeans under elevated O3 concentrations in the production environment, and can provide a platform for conducting genetic screening and elucidation of the mechanisms that underpin genetic variation in productivity at elevated O3 concentrations. Over 40 genotypes of soybean have been investigated for O3 response from 2002-2008 at the soybean FACE experiment in Champaign, Illinois. On average soybean cultivars show a robust linear yield decrease of 37 to 39 kg ha-1 per nL L-1 with increasing exposure to O3 concentrations above 40 ppb, which is approximately the background O3 concentration in the Midwest U.S. The ability of the soybean canopy to intercept solar radiation, the efficiency of photosynthesis, and the harvest index are all negatively impacted by O3. We have identified two cultivars (Pana and Dwight) with varying responses to O3, and used them as parent lines for a recombinant inbred population. In 2011 and 2012, 208 F6 RILs developed from the Pana x Dwight cross were grown at ambient and elevated O3 in the field. Current progress in identifying useful physiological screens, dissecting the genetic basis for O3 tolerance and identifying transgenic strategies to improve O3 tolerance will be discussed.