Is there potential to adapt soybean (Glycine max Merr.) to future [CO2]? An analysis of the yield response of 18 genotypes in free-air CO2 enrichment

Kristen A. Bishop, Amy M. Betzelberger, Stephen P Long, Elizabeth Ainsworth

Research output: Contribution to journalArticle


Rising atmospheric [CO2] is a uniform, global change that increases C3 photosynthesis and could offset some of the negative effects of global climate change on crop yields. Genetic variation in yield responsiveness to rising [CO2] would provide an opportunity to breed more responsive crop genotypes. A multi-year study of 18 soybean (Glycine maxMerr.) genotypes was carried out to identify variation in responsiveness to season-long elevated [CO2] (550ppm) under fully open-air replicated field conditions. On average across 18 genotypes, elevated [CO2] stimulated total above-ground biomass by 22%, but seed yield by only 9%, in part because most genotypes showed a reduction in partitioning of energy to seeds. Over four years of study, there was consistency from year to year in the genotypes that were most and least responsive to elevated [CO2], suggesting heritability of CO2 response. Further analysis of six genotypes did not reveal a photosynthetic basis for the variation in yield response. Although partitioning to seed was decreased, cultivars with the highest partitioning coefficient in current [CO2] also had the highest partitioning coefficient in elevated [CO2]. The results show the existence of genetic variation in soybean response to elevated [CO2], which is needed to breed soybean to the future atmospheric environment.

Original languageEnglish (US)
Pages (from-to)1765-1774
Number of pages10
JournalPlant, Cell and Environment
Issue number9
StatePublished - Sep 1 2015



  • Atmospheric change
  • Biomass partitioning
  • Climate change
  • Crop development
  • Crop yield
  • Food security
  • Global change
  • Harvest index

ASJC Scopus subject areas

  • Physiology
  • Plant Science

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