No abstract

A field experiment was conducted on clay loam soil during kharif, 2017 at Instructional Agronomy Farm, Rajasthan College of Agriculture, Udaipur to find out the best chemical weed management practices in maize. The experiment comprising 13 treatment combinations i.e. weedy check, atrazine 0.5 Kg ha-1 PoE at 10 DAS, atrazine 0.5 Kg ha-1 PoE at 15 DAS, atrazine 0.5 Kg ha-1 PoE at 20 DAS, atrazine  0.5 Kg ha-1  + halosulfuron  0.09 Kg ha-1 PoE at 10 DAS, atrazine  0.5 Kg ha-1  + halosulfuron  0.09 Kg ha-1 PoE at 15 DAS, atrazine  0.5 Kg ha-1  + halosulfuron  0.09 Kg ha-1 PoE at 20 DAS, atrazine  0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 PoE at 10 DAS, atrazine  0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 PoE at 15 DAS, atrazine  0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 PoE at 20 DAS, atrazine  0.5 Kg ha-1  + topramezone 0.025 Kg ha-1 PoE at 10 DAS, atrazine  0.5 Kg ha-1  + topramezone 0.025 Kg ha-1 PoE at 15 DAS, and atrazine  0.5 Kg ha-1  + topramezone 0.025 Kg ha-1 PoE at 20 DAS.These 13 treatment  were replicated thrice in randomized block design with the objectives to find out the effect of herbicides and their tank mix  application on nutrition in plant as well as weed and chlorophyll content of maize and their economics. The minimum NPK  uptake by weeds at harvest also was found under the treatment of atrazine  0.5 Kg ha-1+  tembotrione  0.125 Kg ha-1 PoE at 15 days after sowing. All the weed control treatments increased the chlorophyll content of maize over weedy check. The post-emergence application of atrazine 0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1at 15 DAS  treatment resulted in maximum seed yield (5240 Kg ha-1) which was statistically at par with post-emergence application of atrazine 0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 at 20 DAS (4963 Kg ha-1). The maximum uptake of total nitrogen (144.49 Kg ha-1) and phosphorus (34.99 Kg ha-1) by the crop was observed under application of atrazine 0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 PoE at 15 DAS, while  maximum uptake of potassium (130.42 Kg ha-1) recorded  in atrazine  0.5 Kg ha-1  + topramezone 0.025 Kg ha-1 PoE at 20 DAS which were significantly higher over all other herbicidal treatments.