Impacts of climate change on crop-weed dynamics: Challenges and strategies for weed management in a changing climate

Rising carbon dioxide (CO2) concentrations, global temperature variations, and precipitation changes are key factors influencing future weed dynamics and agricultural productivity. Weeds, having diverse gene pools and physiological plasticity, are likely to exhibit greater resilience and adaptability to changes in CO2 concentrations and temperature, potentially outcompeting crops. The global increase in carbon dioxide emissions by 51% is of concern, given that CO2 accounts for three-fourths of total emissions. Weeds with C3 and C4 photosynthetic pathways may display distinct responses to elevated CO2 and temperature, impacting the dynamics of crop-weed competition. Furthermore, climate change can influence the efficacy of herbicides, further complicating weed management. Understanding and assessing the changes in climatic factors and their interactions at the crop-weed interface is crucial for developing effective weed management strategies in a changing climate. While the positive response of C3 crops to increased CO2 may reduce the competitiveness of certain C4 weeds, the potential emergence of C3 weeds in C4 or C3 crops, particularly in tropical regions, poses a significant concern. Therefore, comprehensive research is needed to formulate adaptive weed management approaches that consider the multifaceted impacts of climate change on crop-weed interactions. This paper emphasizes the urgency of addressing the impact of climate change on weed growth and its implications for weed management in order to ensure sustainable crop production in a changing climate.