Evaluation of New Formulation of Oxyfluorfen (23.5% EC) for Weed Control Efficacy and Bulb Yield in Onion

Abstract

A field experiment were conducted for two years at Agricultural Research Station, Bhavanisagar of Tamil Nadu Agricultural University, during kharif season of 2009 and 2010 to evaluate the new formulation of oxyfluorfen (23.5% EC) on weed control in onion. Weeds constitute one of the biggest problems in agriculture that not only reduce the yield and quality of onion but also utilize essential nutrients. Hence, weed control is essential for increasing onion production. Based on two years field experimentation, it was found that pre-emergence application of oxyfluorfen (23.5% EC) at400 g . ha - 1 gave significantly lower total weed density, weed dry weight and higher weed control efficiency at all the intervals. Application of new formulation of oxyfluorfen (23.5% EC) at200 g . ha - 1 as pre-emergence herbicide can keep the weed density and dry weight below the economic threshold level and increase the bulb weight (42.56 and43.87 g) and yield (15940 and15610 k g . ha - 1 ) in onion. Unweeded control accounted for lower bulb yield which inturn reflected through higher weed index of 60.6 and 56.1 per cent, respectively during both the years, due to heavy competition of weeds for nutrients, space and light .