More or less pesticides with GE crops?
This isn’t a simple question to answer. Studies have shown that the environmental benefits of GE crops are primarily linked to reductions in pesticide use and reductions in tillage. At the same time there are potential environmental impacts of GE crops with respect to how they are used in farming systems. An extensive use of a limited number of pesticides used on GE crops can accelerate the evolution of resistant pest populations, which can lead to increased use of other pesticides.
Why spray at all?
All crop farmers need to manage the pests that can harm their crops. Pesticides are an important tool that many farmers choose to use to help control insects, diseases and weeds on their crop.
Weeds can be a major problem for farmers because they compete with the crops for water, nutrients and space. Herbicide-resistant crops are engineered to withstand a “broad spectrum” herbicide, that is, effective against many different kinds of weeds. These crops can be sprayed by that herbicide without harm and all the weeds will die – an efficient strategy that reduces costs. Before GE varieties were available, farmers sometimes couldn’t grow these crops because there was no effective way to control weeds.