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How do herbicide-resistant crops allow farmers to control weeds?

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DNA extraction and recombinant DNA technology — recombinant DNA The process of DNA extraction is necessary to isolate molecules of DNA from cells or tissues. A series of steps, including the use of protease enzymes to strip proteins from the DNA, are required for isolating pure DNA that is suitable for use in later procedures, such as cloning or sequencing.

Herbicide-resistant crops (HRCs) are genetically modified organisms engineered to withstand specific chemical herbicides, most notably glyphosate.12

These crops allow farmers to control weeds by enabling the application of nonselective herbicides directly over a field of growing crops. Because the HRC plants have been modified—often by introducing bacterial genes that encode an enzyme insensitive to the herbicide—they can survive the treatment while the surrounding weeds are eliminated. This method provides a convenient way to manage weeds that compete with crops for essential nutrients, water, and light.13425

While this technology facilitates effective weed management and supports no-till farming practices that reduce soil erosion, it remains controversial. The widespread use of HRCs has led to increased chemical application, which can negatively impact the environment and has contributed to the emergence of herbicide-resistant "super-weeds," forcing farmers to adopt more diverse weed-management strategies to maintain control.1325