Advances in site-specific weed management techniques for sustainable crop production

Weeds are amidst the major factors that can adversely affect crop yield. Current weed control methods, such as use of synthetic herbicides and mechanical methods, are widely used and effective, but come with drawbacks like environmental impacts, development of herbicide-resistant weeds and limited labor availability. There is an urgent need to address critical issues such as the use of harmful pesticides, pollution control and the environmental impact on agricultural practices. In recent times, innovative methods have been proposed to address existing limitations and transition toward more ecofriendly weed control approaches. The advancement in automation and information technologies has revealed a new era for weed management, allowing physical and chemical control methods to be tailored for the spatial and temporal variability of weed distributions in agricultural fields. Non-chemical weed control methods could reduce reliance on herbicides and soil tillage. Sensor technologies, including spectral imaging, remote sensing and artificial intelligence (AI), are employed to accurately identify and classify weeds. These classifications are then utilized by automated robots to carry out precise mechanical weeding operations. Additionally, imaging and AI-guided robots, in conjunction with unmanned aerial vehicles (UAVs), can assist in both intra-row and inter-row weeding, alongside targeted patch spraying. Site-specific weed management showed around 50 % saving of herbicides by reducing the application dose. This review examines site-specific weed management technologies, assesses their advantages and provides insights onto their potential implementation in agriculture. Nonetheless, further research is needed to incorporate these technologies into conventional agricultural practices.