The Changing Effects of Agro-Climate on Cereal Crop Yields during the Green Revolution in India, 1972 to 2002

Conventionally, agricultural technologies associated with the Asian Green Revolution (GR) have been regarded as a resource-demanding type of technologies which achieve higher crop yields by intensive use of inputs including water, but are therefore sensitive to harsh agro-ecological conditions such as droughts. This study uniquely explores the changes over time in the impacts of climatic conditions and irrigation on cereal crop yields in India during the 31-year period from 1972 to 2002. A district-level panel data set is assembled from several sources, and the yield equations for five major crops (wheat, rice, maize, sorghum, pearl millet) are estimated by combining two-way fixed effect and sample selection models. It is found that climate dependence of crop yields decreased over time, particularly at the later stage of the GR, indicating that GR technologies for these cereal crops have mitigated, rather than aggravated, the adverse effects of climatic conditions on crop yields. Moreover, it is also found that the adoption of irrigation leads not only to directly enhancing crop yields but also to alleviating the negative influences of temperature and rainfall. The results suggest that recent agricultural technologies developed in Asia can be conducive to overcoming harsh production environments in less-favored regions of the world, if proper institutions are in place.