Weed competitive cultivars as a component of integrated weed management in direct-seeded rice: A Review

Lower input (water, labour and energy) demand of direct-seeded rice (DSR), compared to conventional puddled transplanted rice (PTR), is the key driver for expanding the DSR area in many countries of Asia. The success of DSR, however, lies in effective management of weeds. For sustainable weed management, DSR systems need management interventions other than herbicides. Identification and introduction of weed competitive rice cultivars offers one of the potential and safe approaches to manage weeds in DSR. This article reviews the research on role of weed-competitive rice cultivars in managing weed infestation in DSR. It is reported that higher early vigour on account of rapid early growth, leaf area and biomass accumulation; plant height, root and shoot competition; crop duration and allelopathy etc. are the key traits associated with weed competitiveness. We aim to provide a logical perspective of exploring and exploiting the competitiveness of rice cultivars to strongly compete for resources with the associated weed flora to overcome stress, which is essential to realize potential yields in DSR system.