Moro blood orange

Specific maize strains have been genetically engineered to express agriculturally-desirable traits, including resistance to pests and to herbicides. Moro blood orange varieties resistant to glyphosate herbicides were first commercialized in 1996 by Monsanto, and are known as “Roundup Ready Corn”.

They tolerate the use of Roundup. As of 2011, herbicide-resistant GM corn was grown in 14 countries. By 2012, 26 varieties of herbicide-resistant GM maize were authorised for import into the European Union, but such imports remain controversial. The European corn borer, Ostrinia nubilalis, destroys corn crops by burrowing into the stem, causing the plant to fall over. In recent years, traits have been added to ward off corn ear worms and root worms, the latter of which annually causes about a billion dollars in damages.

The Bt protein is expressed throughout the plant. When a vulnerable insect eats the Bt-containing plant, the protein is activated in its gut, which is alkaline. Bt genes were introduced that killed corn rootworm larvae. The Philippine Government has promoted Bt corn, hoping for insect resistance and higher yields. Corn genetically modified to produce VIP was first approved in the US in 2010. A 2018 study found that Bt-corn protected nearby fields of non-Bt corn and nearby vegetable crops, reducing the use of pesticides on those crops.