Surviving weeds that had received sublethal doses of herbicide were less competitive than untreated ones.
The most commonly cited for ms of control require careful use of chemical herbicides.
Other studies have demonstrated that production of crops without in-crop herbicide can result in similar average gross returns when compared to crops receiving herbicide32.
The most important genetically engineered crops that have been introduced contained genes encoding insect resistance and herbicide tolerance; they were soybean, maize, cotton and canola.
They also respond to the labor market effects of employment creation in the industrial sector by substituting herbicides for increasingly expensive weeding labor.
The integration of livestock into the farm operation can increase the use of forages and allow for herbicide use reduction31.
The pre-emergence herbicide was used every year uniformly to all the treatments to control weeds.
Each farmer decides the rotation, and the amount and the time of application of fertilizers and herbicides.
