Molecular mechanisms and biotechnological advances in herbicide resistance: Insights into the development of herbicide-tolerant crops.

Herbicides play a pivotal role in modern agriculture by controlling weed populations and safeguarding crop yields. However, the long-term and extensive use of herbicides has accelerated the evolution of herbicide-resistant weeds, thereby diminishing their efficacy and posing a serious threat to global food security. Recent advances in molecular biology and plant biotechnology have greatly expanded our understanding of herbicide resistance mechanisms and enabled the development of crops with enhanced herbicide resistance. Herbicide resistance genes function primarily by encoding detoxifying enzymes, modifying herbicide target sites, or activating specific metabolic pathways that mitigate herbicidal toxicity. Emerging genetic tools, including transgenic approaches and CRISPR/Cas-mediated genome editing, have further facilitated the precise introduction of resistance traits into major crops. It is noteworthy that this review offers novel insights into the latest CRISPR/Cas applications, including base editing and prime editing for developing novel, non-transgenic herbicide-resistant crops. Furthermore, it provides a systematic overview of advanced strategies for engineering multi-gene stacking traits to combat complex or evolving weed resistance. This review integrates recent progress in elucidating the molecular targets of herbicides and the underlying resistance mechanisms, and highlights the potential of modern biotechnological strategies for engineering herbicide-resistant crops to promote sustainable and environmentally responsible weed management.