Which practice is most likely to increase herbicide resistance in plants?

The continual use of the same herbicides from the same chemical family is most likely to increase herbicide resistance in plants. This practice exposes the target weed population to the same mode of action repeatedly, which can lead to the survival and proliferation of resistant individuals. Over time, weeds that can tolerate or resist the effects of that specific herbicide will reproduce, passing on their resistance traits to the next generation.

In contrast, strategies like alternating chemical families or rotating crops effectively disrupt the selection pressure that encourages resistance, as they mix the modes of action that the weeds face. The application of mixed herbicide formulations can also help mitigate resistance by utilizing different modes of action concurrently, making it more challenging for weeds to adapt. Therefore, relying exclusively on one chemical family sets the stage for resistance development among target weed populations.