Bio-efficacy of Some Herbicides on Rumex dentatus L.

Several herbicides have been tested for their bio-efficacy on Rumex dentatus, under non-crop situation (1998–99) and in wheat crop (1999–2000). First year metsulfuron-methyl and isoproturon at their higher doses (0.01 and 1.50 kg ha⁻¹ respectively) and chlorsulfuron at both the doses (0.02 and 0.04 kg ha⁻¹) gave excellent long-term control of the weed. The efficacy of 2, 4-D lasted up to 15 days after treatment (DAT) of herbicides and that of sulfosulfuron up to 30 DAT. In second year, isoproturon (0.75 kg ha⁻¹), metribuzin (0.20 kg ha⁻¹), metsulfuron-methyl (0.008 kg ha⁻¹) and chlorsulfuron (0.03 kg ha⁻¹) proved highly superior to all other treatments in reducing the population and fresh biomass accumulation of Rumex plants. Metribuzin exhibited its maximum effect at 30 DAT, whereas isoproturon at 40 DAT. Isoproturon, however, resulted in 100% control of the weed. Metribuzin produced significantly higher wheat yield than all other treatments except isoproturon, bentazon+MCPA (pre-mix) and chlorsulfuron. Metsulfuron-methyl and bentazon, although remained intermediate in wheat yield output, were superior to unweeded control.