EFFECT OF PRE AND POST EMERGENCE HERBICIDES ON HERBICIDE EFFICIENCY INDEX, PRODUCTIVITY AND ECONOMIC EFFICIENCY IN TRANSPLANTED RICE

Field experiment was conducted to manage the weeds by pre and post-emergence herbicide combinations in transplanted rice during February-May 2020 at the Experimental Farm, Department of Agronomy, Annamalai University, Tamil Nadu, India.Treatments comprised of pre-emergence herbicides (butachlor, pretilachor, and pyrazosulfuron ethyl) and post-emergence herbicides (bispyribac sodium, metsulfuron methyl + chlorimuron ethyl, fenoxaprop-p-ethyl, and triafamone + ethoxysulfuron), hand weeding twice (20 and 40 DAT), and an unweeded control plot.Among the weed management practices, hand weeding twice at 20 and 40 days after transplanting (DAT) notably reduced the weed counts and increased crop resistance, higher growth and yield attributes, and grain yields.It was statistically on par with the application of pyrazosulfuron ethyl 20 g ha -1 PE at 3 DAT, followed by bispyribac sodium 25 g ha -1 PoE at 20 DAT.Best, it was superior to hand weeding twice in terms of net income ( 48,997) and BCR (2.06).The results suggested that the application of pyrazosulfuron ethyl 20 g ha -1 PE at 3 DAT, followed by bispyribac sodium 25 g ha -1 PoE at 20 DAT, was the best broadspectrum effective herbicide in order to manage the diverse weed flora in transplanted rice.