Bio-efficacy of sequential application of herbicides on weeds and productivity of maize (Zea mays)

The field efficacy of pre- and post-emergence herbicide combinations for control of complex weed flora in maize (Zea mays L.) was evaluated in a field study conducted at Research area of Department of Agronomy, Chaudhary Charan Singh Haryana Agricultural University, Hisar (Haryana) during kharif 2020-21. The experiment was performed in randomized block design with 18 treatments and replicated thrice. Cyperus rotundus, Echinochloa colona, Dactyloctenium aegyptium and Convolvulus arvensis were the major weeds in experimental area. The season long growth of weeds reduced maize yield up to 65.6% during the season. Sequential application of atrazine 1000 g ha⁻¹ or 750 g ha⁻¹ as PRE fb tembotrione 120 g ha⁻¹ + S at 35 DAS resulted in minimum weed density, dry weight of weeds and maximum weed control efficiency at 20, 50 and 80 DAS and followed by atrazine 750 g ha⁻¹fb topramezone 25 g ha⁻¹ at 35 DAS compared to sole application of tembotrione and topramezone. Various herbicide treatments did not show any significant effect on phenology of maize. Significantly higher number of grains per cob, cob yield with husk, grain andand biological yield and higher B:C ratio was reported under atrazine 1000 g ha⁻¹ as PRE fb tembotrione 120 g ha⁻¹ + S at 35 DAS and followed by atrazine 750 g ha⁻¹ as PRE fb tembotrione 120 g ha⁻¹ + S at 35 DAS.