Nutrient content in mustard and associated weeds as influenced by nitrogen levels, planting geometry and weed control methods

A field experiment was conducted at J.N. Krishi Vishwa Vidyalaya, Jabalpur during the winter season of 1996–97 and 1997–98 to study the effect of increasing levels of nitrogen, planting geometry and herbicides on the nutrient content of mustard and associated weeds. Treatments consisted of combinations of 4 nitrogen levels (0, 40, 80 and 120 kg ha⁻¹) and two planting geometry (uni and bi-directional sowing) as main plots and 2 herbicides (isoproturon 1.0 and oxadiazon 0.75 kg ha⁻¹ as pre-emergence) along with hand weeding at 30 days after sowing (DAS) and wecdy check as sub-plot. Results revcaled that NPK contents in both crop and weeds decreased with plant age, the highest being at 25 DAS and the lowest at harvest. Application of 120 kg N ha⁻¹ significantly increased nutrients (NPK) content in crop and decreased in weeds compared to no nitrogen application. Planting geometry failed to affect nutrient content both in crop and weeds. Application of herbicides and hand weeding significantly increased nutrients content in mustard as compared to weedy check.