Are GM crops better for the environment?

In this second report of GMO Inquiry 2015, investigate the environmental impacts of genetically modified (GM; also called genetically engineered or GE) crops in Canada, and around the world. After 20 years, most of the GM crops grown in Canada are herbicide-tolerant, and the rest are insect-resistant (some are both). The widespread cultivation
of glyphosate-tolerant crops, in particular, has driven up the use of glyphosate-based herbicides. This increased use of glyphosate has resulted in the emergence and spread of glyphosate-resistant weeds. In response, biotechnology companies have genetically engineered crops to be tolerant to the older herbicides 2,4-D and dicamba. These GM crops will further increase the herbicide load in the environment and lead to even more herbicide-resistant weeds. GM insect-resistant (Bt) crops have reduced insecticide use in some countries. The Canadian government has not monitored the impact of Bt crops on insecticide use in Canada. However, insects are beginning to develop resistance to Bt crops in the US and other countries, and farmers are turning to other insecticide applications to control them. Additionally, Bt plants themselves produce insecticidal toxins that are released into the environment.