Over 12 thousand years ago people began planting and saving seed. Agriculture flowered and civilizations were born. In China thousands of varieties of rice were grown. Over 5,000 kinds of potatoes were cultivated worldwide. In the US alone more than 7,000 varieties of apples were grown in the 19th century. In the 20th century the phase of farming underwent a radical change. The manufacture of nitrogen-based bombs during WWI led to the development of nitrogen-based chemical fertilizers. Nerve gas developed during WWII was slightly modified to make insecticides. DDT was the hero of its generation. New technologies promised higher yields, increased food production, cheaper prices and greater availability. By the mid-20th century these technologies, along with new developments in plant-breeding, led to the Green Revolution.
I think the people who first imagined the Green Revolution had good hearts. Lots of people are starving around the planet. That's long been the case in human civilization. Their thinking was if we could just systematize agriculture like we did industry in the 1800s and bring it worldwide, bring one system that works, we can solve the problems that people have long had with agriculture.
The next several decades saw a remarkable increase in production. Year after year huge fields were planted with only one variety of crop. These monocultures created an ecological vacuum that insects and disease could exploit. This uniformity has led to some of the greatest agricultural catastrophes of mankind. In the mid-1800s very few varieties of potatoes were cultivated in Ireland. When they became diseased, one million people died. When the same potato blight attacked Peru they suffered fewer consequences. Today only 4 varieties of potatoes are widely grown.
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insecticides n. A chemical substance used to kill insects. 殺蟲劑
DDT n. Dichloro-diphenyl-tricgloroethane 二氯二苯三氯乙烷, 滴滴涕(一種殺蟲劑);
blight n. Any of numerous plant diseases resulting in sudden conspicuous wilting and dying of affected parts, especially young, growing tissues. 枯萎病