Technology and U.S. corn yields: plateaus and price responsiveness.
1983
Menz K.M. | Pardey P.
Extract: An econometric analysis of aggregate U.S. corn yields for the period 1954-80 indicates a much reduced but still measurable contribution of nitrogen to corn yields. The current annual yield increase from non-nitrogen technologies, principally genetic improvements, is around 1.0 bu/ac/yr. The overall combined increase from nitrogen and non-nitrogen technologies is now around 1.3 bu/ac/yr -- well below the average annual rate since 1954 of 2.3 bu/ac/yr. However, a yield plateau has not yet been reached. Concomitant with the decline in the impact of additional nitrogen, the price responsiveness of U.S. corn yields has declined to insignificance. This has important consequences for estimates of corn supply response to price changes.
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