Abstract

                                : Results of earlier investigations on application of weedicides on rice crop indicate that post-emergence application of a number of 2, 4-D and M. C. P. A. derivatives have effectively controlled non-grass weeds and increased yield when applied five to six weeks after transplanting (Ryker, 1947; Vachhani and Chavdhari, 1955; Bhardwaj and Varma, 1959; Vachhani et. al., 1963; Sahu and Bhattacharya, 1964). However the dominant weed species infesting rice field in this region are mostly grasses. A newly introduced herbicide, Stam F-34 (3-4 dichloro- propionanilide) has been reported to offer a great promise of controlling both grasses and non-grasses, without injuring the rice crop (dewit, 1961; Van Rijn, 1963; Nair et. al., 1964; Smith, 1265; Mukhopadhyay, 1965). The present investigation was, therefore, planned to study the relative efficiency of different herbicide with and without interculturing in controlling the weeds associated with rice crop and their effects on the grain and straw yields.

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