Since 2008, GMO crops have accounted for more than 80% of the corn and soybean crops planted in the U. S. Corn (maize) seeds are modified with two genes: one kills insects that eat the seed and one allows the seed to tolerate glyphosate, a herbicide
commonly used in weed killers like Roundup. Soybeans are modified with just one glyphosate-resistant gene. Since 2008,
scientists at the University of Virginia have been monitoring the effects of planting GMO corn and soybeans within farm
ecosystems. The UVA study found evidence that both corn and soybean farmers have increased herbicide use during the last five
years and the scientists concluded that the planting these GMO crops are having a negative impact on the local environment. Why?
ALL BUT ONE choice provides a valid reason.
ght
A)
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Bols
Increased herbicide use results in increased contamination of aquatic
ecosystems
B)
Farmers resort to using additional chemicals as glyphosate-resistant
weeds evolve.
The cultivation of GMO's led to a significant increase of yield compared to
the non-GMO varieties
D)
Herbicides can have unintended consequences for nontarget plant species,
thereby reducing plant biodiversity