No yield benefit found in GMs when US compared to W. Europe
"Nonetheless, GM crops are not a solution, in part because they are controlled by strict IP instruments. Despite the claims that GM might be needed to feed the world, we found no yield benefit when the United States was compared to W. Europe, other economically developed countries of the same latitude which do not grow GM crops. We found no benefit from the traits either." (pg. 13) p.5. "Between 1961 and 1985 the United States produced on average approximately 5,700 hg/ha more maize per year than did W. Europe. By the mid-1980s, there was a significant change in yield in our comparison countries (Figure 1). Between 1986 and 2010, W. Europe's yield averaged 82,899 hg/ha, just slightly above United States yields of 82,841 hg/ha (Table 1). Comparing W. Europe with the United States for the entire period 1961–2010 (Figure 1), the average yields were not significantly different (ANOVA: F 1,98 = 0.53; P = 0.47). These results suggest that yield benefits (or limitations) over time are due to breeding and not GM, as reported by others (Gurian-Sherman 2009), because W. Europe has benefitted from the same, or marginally greater, yield increases without GM." Need GMOs to feed world? No. Jury is in! NON-gmo W. Europe has for decades produced corn yields parallel w US GMO farms.http://www.tandfonline.com/doi/pdf/10.1080/14735903.2013.806408
Source: Jack A. Heinemann et al., "Sustainability and innovation in staple crop production in US Midwest", 2013, International Journal of Agricultural Sustainability, http://www.tandfonline.com/doi/pdf/10.1080/14735903.2013.806408 [verified 4/15/14]