Conclusions • There have been large quality changes in seeds due to hybridization, genetic engineering, and conventional breeding. • We use hedonic regressions to account for quality change. The adjusted quantities are close to 50 percent higher in earlier time periods. • New genetic traits have large effects on the price of seed and we also expect large effects on quality-adjusted quantity in more recent years. • This will update the Fernandez-Cornejo seed AIB 786 from 2004 and the Fernandez-Cornejo et al. seed ERR 162 from 2014.
