Over-reliance on the herbicide glyphosate (commonly known as Roundup) has led to more weeds developing a genetic resistance.

Glyphosate is often used in conjunction with seeds that are genetically modified to be resistant to the herbicide. The herbicide kills the weeds, while the crop remains unharmed.

Companies are now racing to develop seed with resistance to multiple herbicides, allowing stronger herbicides to be used against weeds. Researchers warn that this might not be effective in the long term and may make other strategies, such as interacted weed management, harder to implement.