Rice experiences severe competition from weeds. Losses due to weeds range from 30 to 100% under moderate to severe infestations. Of late, weedy rice infestation is a serious threat in traditional rice belts of the country as it affects crop production, harvest quality and farmers income. Weedy rice is a complex of Oryza morphotypes widely distributed in commercial rice fields, especially in areas where farmers have switched to direct seeding due to labour shortage and high wages. India has the earliest history of rice cultivation and introgression between perennial wild rice and annual cultivated rice has given rise to highly variable population of weedy/wild rice forms, including annuals and perennials. Indian weedy rice was reported to be Oryza sativa f. spontanea, belonging to the indica group. Being a conspecific weed, weedy rice is morphologically and biochemically similar to cultivated and wild counterpart species; complete control of weedy rice by hand-weeding or herbicides is impractical. Heavy infestation of weedy rice and subsequent reduction in rice crop yields in India during recent years has forced farmers to abandon rice cultivation in many areas. Management of weedy rice infestation is complex because of its morphological similarityto cultivated rice and non-availability of selective herbicides. Extensive research showed several facts about Indian weedy rice biology and ecology and also standardized package of practices for the management of weedy rice in direct seeded puddled rice.
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