Abstract
In this paper, the likely effect of climate change (such as change in atmospheric CO2, rain and temperature) on the competitivenes of major weeds of the rice-wheat cropping system in northwest India, and the consequences of changing climate and weed community composition for weed management are discussed. Integrated weed management strategies need to be developed, which target the prevention of weed invasion, recruitment and reproduction. Such strategies may include combination of optimal fertilizer schedule, summer ploughing, crop rotation, land preparation, modifying plant geometry, stale seedbed techniques, planting time, seed rate and use of competetive cultivars. Knowledge of weed ecology and biology could be used as a tool for effective weed management in future climate change.