Answer :
The use of improved plant hybrids and agricultural chemicals can explain this change. It was part of the Green revolution.
What was the Green Revolution?
The Green Revolution refers to a period from the 1950s to the 1960s in which high-yield crop varieties were developed.
The development of high-yield varieties and the use of fertilizers help to suddenly increase crop yields, especially in developing countries.
The Green revolution was so impressive that the creator of new wheat-rice varieties Norman Borlaug was awarded the Nobel prize to help to alleviate hunger in the world.
Learn more about the Green Revolution here:
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