Measuring the Potential Contribution of Plant Breeding to Crop Yields: Flue‐Cured Tobacco, 1954–87

Abstract

Measurements are made of plant breeders' success in increasing potential flue‐cured tobacco yields from 1954 to 1987 in North Carolina. Nongenetic sources of yield increases are measured by the yield levels of a standard variety. New genetic material accounted for between 20% and 35% of yield increases on research station plots in the three tobacco‐growing regions. Recent genetic contributions have been small. The slowdown is not attributable to a federal tobacco policy shift in 1965 that slowed the growth in grower yields. There is also no evidence that tobacco breeders increased their output in response to the Plant Variety Protection Act of 1970.

Intellectual Property Rights and the Ascent of Proprietary Innovation in Agriculture

“…Perrin, Kuhnen, and Ihnens (1983) and Babcock and Foster (1991) were unable to detect a statistically significant shift in soybean and tobacco yields, respectively, when the Act passed, despite apparent increases in private soybean R&D spending and the dominance of the private sector in tobacco breeding. Carew and Devadoss (2003) detect a positive impact of Plant Breeders Rights on Canadian canola yields in some specifications, but this effect disappears when time fixed effects are included.…”

But are they Meritorious? Genetic Productivity Gains under Plant Intellectual Property Rights

“…Babcock and Foster (1991) again used variety trial data (in this case from North Carolina) to examine the effect of PVP on tobacco variety releases and yields over the period 1954–1987. The study found no evidence that tobacco breeders increased their output in response to the PVP Act of 1970.…”

“…As a result, we follow a variety trials data‐based comparison approach 9 . As Babcock and Foster (1991) note, measures of technical change from research station data can, at best, be interpreted as potential technical change. In addition, because the varietal trial data are not generated in response to the same economic incentives faced by growers, the response of grower yields to changes in input use cannot be measured from experimental trials.…”

“…We follow the Babcock and Foster (1991) justification for identifying the dependent variable as the yield difference between the target variety and that of a localised reference 10 . Assuming that all test varieties (including the reference variety) are affected proportionally by localised growing conditions, this difference variable effectively adjusts for these differing conditions.…”

Potential economic impacts of terminator technologies: policy implications for developing countries

“…There have been a few studies that have assessed the impact of PVP in the US and Latin American countries (Perrin, Kunnings, and Ihnen, 1983;Butler and Marion, 1985;Kalton, Richardson, and Frey, 1989;Babcock and Foster, 1991;Jaffe and Van Wijk, 1995;Butler, 1996;Frey, 1996;Alston and Venner, 1998). There have been a few studies that have assessed the impact of PVP in the US and Latin American countries (Perrin, Kunnings, and Ihnen, 1983;Butler and Marion, 1985;Kalton, Richardson, and Frey, 1989;Babcock and Foster, 1991;Jaffe and Van Wijk, 1995;Butler, 1996;Frey, 1996;Alston and Venner, 1998).…”