N, P and K Uptake by Crop and Weed as Influenced by Nutrient Levels and Weed Management in Mustard

A field experiment was conducted in Rabi season of 2018-19 and 2019-20 at Research farm of Bihar Agricultural College, Sabour to assess the impact of nutrient and weed management on N, P and K uptake by crop and weed in mustard. This experiment with 3 nutrient levels (N1-soil test-based recommended dose of fertilizer (RDF), N2-100 % RDF, N3-125 % RDF) in main plot; 8 weed management (W1-Weedy, W2-Hand weeding (HW), W3-pendimethalin, W4-pendimethalin followed by (fb) quizalofop, W5-pendimethalin fb clodinafop, W6-oxyflourfen, W7-oxyflourfen fb quizalofop, W8-oxyflourfen fb clodinafop) in sub plots, laid in split plot design. Results indicated that in 2018-19, N, P and K uptake by mustard was found maximum under 125% RDF. Hand weeding exhibited highest N, P and K uptake by crop over weedy. Among herbicides, maximum N, P and K uptake by crop was noted with pendimethalin 30 EC 1.0 kg a.i. ha-1 PE fb quizalofop 5 EC 60 g a.i. ha-1 PoE. In 2019-20, hand weeding at 25 and 50 DAS along with 125% RDF exhibited highest N, P and K uptake by crop. Among herbicides, application of pendimethalin 30 EC 1.0 kg a.i. ha-1 PE fb quizalofop 5 EC 60 g a.i. ha-1 PoE along with 125% RDF exhibited highest N, P and K uptake by the crop. In both the years 2018-19 and 2019-20, hand weeding at 25 and 50 DAS along with 125% RDF exhibited N uptake by weeds, zero value being lower than weedy. In 2018-19, application of pendimethalin 30 EC 1.0 kg a.i. ha-1 PE fb quizalofop 5 EC 60 g a.i. ha-1 PoE along with 125% RDF exhibited the lowest N and K uptake by weeds. Among nutrient levels, application of 125% RDF exhibited the lowest P uptake by weeds, however, among herbicides; application of pendimethalin 30 EC 1.0 kg a.i. ha-1 PE fb quizalofop 5 EC 60 g a.i. ha-1 PoE registered the lowest P uptake by weeds. In 2019-20, application of pendimethalin 30 EC 1.0 kg a.i. ha-1 PE fb quizalofop 5 EC 60 g a.i. ha-1 PoE along with 125% RDF exhibited the lowest N, P and K uptake by weeds. Thus it was concluded that pendimethalin 1.0 kg a.i. ha-1 PE fb quizalofop 60 g a.i. ha-1 PoE along with 125% RDF (100:50:50:25:6.25 kg NPKSZn ha-1) enhanced N, P and K uptake by crop though hand weeding at 25 and 50 DAS along with 125% RDF (100:50:50:25:6.25 kg NPKSZn ha-1) exhibited significant improvement in nutrient uptake by crop.