The genetic engineering (GE) of crops helps farmers in several ways. Using GE to employ herbicide tolerance traits in crops is very helpful. I like to think of the traits as additional tools in my agronomic toolbox. This is particularly true for our soybeans. There are of course herbicide options for conventional soybeans, but the chemicals available aren't as plentiful or possibly even as effective as all the choices I have for a grass crop like corn. Added herbicide traits like Roundup Ready, LibertyLink, and in the near future the possibilities of 2,4-D and dicamba tolerance increase the range of products I can use on a soybean crop to combat specific weed issues. Just because I plant an herbicide tolerant traited crop does not mean I have to use that herbicide. For example, about half our corn crop each year is Roundup Ready. But we almost never spray Roundup on those acres. We like to rotate to another herbicide(s) when a field's rotation is in corn rather than soybeans because we generally use Roundup on all our beans at this time. Changing up the modes of action of weeds with different herbicides keeps weed resistance at bay. But if we do get in a tough spot with our corn with foxtail or some other grass we could easily come clean that weed issue up with Roundup which is great for killing grass weeds. So I don't have to employ the added trait, but I can. GE crops can be treated like their conventional counterparts.
On our farm Bt corn has been helpful in fighting off pests that want to eat our corn. The pests cause direct damage obviously, but the injuries they leave behind can also invite in disease as well. Since the Bt corn must be fed on by a pest this means we are seeking out the target pests of our crop with this GE use of insecticide. I came back to our family farm in 2009. Due in part to Bt traits, treated seed, and environmental conditions we have only sprayed a 30 acre area for corn pests one time in the last seven seasons. We raise about 840 acres of corn each year. We have also stopped applying liquid insecticide with our planter. So from a chemical standpoint all our pest control for corn is within the corn plants themselves. This saves us money by not hiring custom spraying as we don't have our own sprayer. It also saves on chemical costs, and prevents blanket applications of insecticides that could also catch beneficials that we don't want or need to kill. And because we aren't sending sprayers across fields for insect control those sprayers don't need loaded with fuel, and they don't need water to carry the pesticides if they are sitting idle.
Other traits like drought tolerance and Nitrogen use efficiency are going to go a long way towards future sustainability.
Moderator Note: There are no genetically engineered livestock currently available on the market.