Although there has been improvements in overall agricultural
total factor productivity (TFP) since the 1990 s, with TFP accounting
for nearly three-quarters of the total growth in agricultural output
worldwide over the period 1991–2010 (Fuglie 2012), studies conducted in East and South Asia rice bowls suggests that annual
growth rates of TFP in rice production, which increased significantly
as a result of the Green Revolution, have been declining, especially
in India, the world second largest rice producer. Reasons for this
declining TFP growth rate include: (1) substantial lessening of
investments—notably public-sector investments, (2) displacement
of cereals from better lands by more profitable crops, including
horticultural crops; (3) diminishing returns to modern varieties
when irrigation and fertilizer use are already high; and (4) falling
cereal prices relative to input costs, which makes additional
intensification less profitable