Weedy rice and its management -A review

Weedy rice is a complex of Oryza morphotypes widely distributed in areas where farmers have switched to direct seeded rice. It is progeny of crosses between wild rice and cultivated rice. The major characteristics are taller plants, easy shattering, grains having awns and high percentage of red rice in milled rice. Weedy rice competes with cultivated rice for sunlight, space, water and nutrients resulting in reduction in rice yield. It is difficult to be managed because of its morphological similarities with cultivated rice. Best methods for preventing the infestation of weedy rice are use of clean seed, use of pre germinated seed, stale bed preparation, roguing, crop rotation, application of pre emergence herbicides and Integrated Weed Management (IWM). Recently, biotechnology approach using genetically modified herbicide tolerant rice varieties may be an efficient strategy.