Crop production systems that require chemical fertilizers, pesticides, machinery for
tillage, and irrigation water are expensive. In countries such as India, they have started
to undermine the water security of future generations, contributing to soil and water
pollution particularly when synthetic pesticides are not used properly. It is true that
agriculture as practiced 100 years ago without modern inputs had lower productivity
than present systems of production. However, many premodern practices, such as the
use of organic manures to enhance soil fertility and of herbal extracts to protect crops,
can be made more efficient by the scientific knowledge that has been gained over
the past century, making crop production more sustainable while still achieving high
productivity
