Most genetically modified (GM) crops fall into one of two categories. They are either engineered to resist chemical herbicides, or they are engineered to produce insecticides in the plants themselves. This means crops are designed either to tolerate specific broad-spectrum herbicides such as glyphosate or glufosinate, which kill the surrounding weeds, but leave the cultivated crop intact, or they produce a protein that is toxic for pests feeding on them.
Herbicide-resistant (HR) crops
GM herbicide-resistant crops have been grown commercially since the mid-1990s, mostly in North and South America. Cultivating herbicide-resistant crops promotes, and significantly increases, the use of chemical herbicides, such as Monsanto’s ‘Roundup’ and Bayer’s ‘Liberty’.
However, over time, weeds develop resistances to the herbicides, which leads to the use of even more herbicides that are even more toxic.
This forces farmers onto an endless chemical treadmill. Weed resistance continues to increas...
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