Research and Productivity in Wheat 

 and Maize: An International Analysis 



Increased world food production, reviewed in chapter 1, was due 

 to a combination of increases in areas and higher yields. This 

 chapter analyzes the contribution of agricultural research to the 

 increases in yield in two crops: wheat and maize. 



The study covers sixty-four wheat-growing and forty-nine 

 maize-growing countries during the 1948-68 period (the Green 

 Revolution had little impact during this period).' Average yield 

 increases for these countries were 2 percent per annum in wheat 

 and 3 percent in maize. 



A crucial problem in any empirical study is the availability and 

 quality of data. The only available data on crop research are 

 publications. 2 Wheat-and maize-related publications were tabu- 

 lated from Plant Breeding Abstracts, which attempts to cover all 

 significant research work in plant-breeding and related subjects 

 in the world, and were classified by country by first author's ad- 

 dress. Appendix 2 presents numbers of publications by country. 



The analysis is restricted to only two crops to enable the use of 

 a simple physical measure of productivity — yield per unit of land. 

 The restriction meant that no crop-specific data on inputs other 

 than land, area harvested, were included. This shortcoming is not 



This chapter draws on Evenson and Kislev (1973). 



1 . I n 1 968/69, the last year of the period, area sown to Green Revolution high- 

 yielding varieties was less than 4% of the world's wheat-growing area (less than 

 0.4% in 1966/67). In India, however, this share reached 30% in 1968/69 (3% in 

 1966/67). See Dalrymple (1972) for data on the spread of the new varieties. 



2. Sec chapter 2 for a discussion of publication counts as a measure of research 

 output. 



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