1. In the US maize yields have accelerated in the last ten years actual breeding plus cultural practice gain Troyer, A.F. (2006) Adaptedness and Heterosis in Corn and Mule Hybrids. Crop Science, 46, 2, pp 528-543 http://crop.scijournals.org/cgi/content/abstract/cropsci;46/2/528http://crop.scijournals.org/cgi/content/abstract/cropsci;46/2/528 AND http://www.botanischergarten.ch/Bt/Troyer-Adaptedness-Heterosis-2006.pdf Average U.S. corn yields and kinds of corn, CivilWar to 2004. ‘‘b’’ values (regressions kg bu21) indicate production gain per unit area per year (USDA-NASS, 2005)

2. corn yields in France and Italy in the last 10 years fail to show the same trend Source; Eurostat

3. Heinemann, J. A., M. Massaro, D. S. Coray, S. Z. Agapito-Tenfen and J. D. Wen (2013), Sustainability and innovation in staple crop production in the US Midwest International Journal of Agricultural Sustainability, pp. 1-18, http://dx.doi.org/10.1080/14735903.2013.806408 AND http://www.ask- force.org/web/Sustainability/Heinemann-Sustainability-Innovation-20130620.pdfhttp://www.ask- force.org/web/Sustainability/Heinemann-Sustainability-Innovation-20130620.pdf

4. Heinemann, J. A., M. Massaro, D. S. Coray, S. Z. Agapito-Tenfen and J. D. Wen (2013), Sustainability and innovation in staple crop production in the US Midwest International Journal of Agricultural Sustainability, pp. 1-18, http://dx.doi.org/10.1080/14735903.2013.806408 AND http://www.ask- force.org/web/Sustainability/Heinemann-Sustainability-Innovation-20130620.pdfhttp://www.ask- force.org/web/Sustainability/Heinemann-Sustainability-Innovation-20130620.pdf

5. Heinemann, J. A., M. Massaro, D. S. Coray, S. Z. Agapito-Tenfen and J. D. Wen (2013), Sustainability and innovation in staple crop production in the US Midwest International Journal of Agricultural Sustainability, pp. 1-18, http://dx.doi.org/10.1080/14735903.2013.806408 AND http://www.ask- force.org/web/Sustainability/Heinemann-Sustainability-Innovation-20130620.pdfhttp://www.ask- force.org/web/Sustainability/Heinemann-Sustainability-Innovation-20130620.pdf

6. Recalculation from Heinemann, J. A., M. Massaro, D. S. Coray, S. Z. Agapito-Tenfen and J. D. Wen (2013), Sustainability and innovation in staple crop production in the US Midwest International Journal of Agricultural Sustainability, pp. 1-18, http://dx.doi.org/10.1080/14735903.2013.806408 AND http://www.ask-force.org/web/Sustainability/Heinemann-Sustainability-Innovation-20130620.pdf C. Preston Recalculation from Heinemann, J. A., M. Massaro, D. S. Coray, S. Z. Agapito- Tenfen and J. D. Wen (2013),

7. C. Preston Recalculation from Heinemann, J. A., M. Massaro, D. S. Coray, S. Z. Agapito- Tenfen and J. D. Wen (2013),

8. Christopher Preston: Short version: rate of yield increase of corn in US has increased since 1996 compared with prior. Rate of yield increase in Western Europe has decreased since 1996, compared with prior. Although none of the rates are significantly different. Rate of yield increase of canola in Canada has increased since 1996 compared with prior. Rate of yield increase in Western Europe has decreased since 1996, compared with prior. The rates are significantly different. Rate of yield increase in Canada prior to 1996, was significantly lower than the others. I noticed the major error in the date that GM crops were introduced. The paper states 1986; however, it was in 1996. So I went back to the source data from FAOSTATS and plotted the data from 1961-1995 and then from 1996-2011 and calculated the average yield increase over the two periods. (C. Preston, email from June 27, 2013 christopher.preston@adelaide.edu.auchristopher.preston@adelaide.edu.au