Spatial and Temporal Trends in the Yields of Three Major Crops: Wheat, Rice and Maize in India.

India is one of the largest landmasses under crop cultivation with staple consumption of food security crops. Post green revolution (since 1967), there has been a steady March towards self-sustainability in food production. Though the general trends speak of an increase in crop yields, the detailed study on decade wise trends and fast approaching state of stagnation in crop yields is largely missing. The present manuscript is the first study examining the crop yield trends of three major food crops—wheat, rice, and maize across Indian states. The four types of regression models were fitted on the annual yield data from all the 29 Indian states over the period 1967–2017. The best-fit statistical models were chosen using the Akaike information criterion. Our results suggest that (1) Wheat yields in 13 Indian states, rice yields in eleven Indian states, and maize yields in six Indian states are now not improving. (2) The yields in ~ 76% of wheat harvested area (~ 18.5 million hectares), ~ 47% of rice harvested area (~ 19.5 million hectares), and ~ 18% of maize harvested area (~ 1.2 million hectares) are not improving for the recent decade. The detailed mapping of current crop yield trends across Indian states is the first step towards achieving a bigger goal of identifying the responsible factors affecting current crop yield trends and then identifying and recommending appropriate mitigation strategies. [ABSTRACT FROM AUTHOR]