Comparative efficacy of herbicidal and manual weed control in cumin (Cuminutn cyminum) at different levels of nitrogen

A field study was conducted during the winter seasons of rabi 2000–2001 and 2001–2002 to investigate the comparative efficacy of herbicidal and manual weed control in cumin (Cumimum cyminum L.) at different levels of nitrogen. All the weed-control treatments significantly reduced the density and dry weight of weeds and nutrient depletion as compared to weedy check. Two hand-weedings at 25 and 50 days after sowing was found to be the best treatment in reducing the above weed parameters. It attained the maximum weed-control efficiency (87.9%) and seed yield of cumin (5.50 q/ha). Among herbicides, the lowest density and dry weight of weeds and the maximum weed-control efficiency (84.3%) was obtained with pre-plant Trifluralin at 2.16 kg/ha. For seed yield (4.94 q/ha) and weed-competition index (10.2%), Trifluralin at 1.08 kg/ha was found the best herbicidial treatment. Pendimethalin at 1.0 kg/ha (pre-emergence) also controlled the weeds more effectively (79.3%) than lower doses of Trifluralin and Fluchloralin at 1.125 kg/ha and resulted 242.9% higher seed yield than the control. Application of 30 kg N/ha was the most remunerative dose for cumin with respect to seed yield.