Bioefticacy of herbicides in late sown wheat (Triticum aestivum)

Abstract

A field study was conducted during winter (rab ) seasons of 2000 2002 at Varanasi, to study the bioefficacy of oryzalin (0.05, 0.75, 1.00,1.25 and 1.50 kglha), triasulfuron (0.01 5 and 0.020 kglha), pendimethalin (1.0 kglha) as pre emergence and dicamba (0.025 kglha) as post emergence in late sown wheat (Trticum aestivum L. emend. Fiori Paol.). All the herbicide treatments reduced the density and dry weight of narrow and broad leaved weeds significantly compared with weedy check. Pre emergence application of oryzalin at 1.25 kglha had minimum population and dry weight of weeds compared with other herbicides and their doses. Dicamba at 0.025 kglha was the most effective against broad leaved weeds compared with other herbicides. Triasulfuron at 0.020 kglha proved more effective than its lower dose (0.015 kglha) and controlled both narrow and broad leaved weeds. The maxi mum weed control efficiency (76.65%) and grain yield (27.48 qlha) were recorded with oryzalin at 1.25 kg/ha, fol lowed by pendimethalin at 1.0 kglha and triasulfuron at 0.020 kglha.