Efficacy of Different Pre and Post Emergence Herbicide Application on Late Sown Maize Crop Under Variable Planting Density

Abstract

Planting density (PD) is an important management practice that plays a crucial role in crop growth and weeds infestation. Weeds control methods also play an indispensable role to control the weeds infestation. Therefore, present study was conducted to determine the effect of different weed control methods and PD on growth, yield and quality of maize grown under semi-arid conditions. The study was comprised of weedy season, weed free, S-metalachlor @ 1920 g a.i. ha⁻¹, S-metolachlor + atrazine @ 740 g a.i. ha⁻¹ + 550 g a.i. ha⁻¹, mesotrione + atrazine @ 687.5 g a.i. ha⁻¹, S-metolachlor + atrazine @ 740 g a.i. ha⁻¹ + 550 g a.i. ha⁻¹ + mesotrione and atrazine @ 687.5 g and different PD; 12 and 20 cm. The results indicated that taller plants with maximum rows/cob, cob length, grains/cob, 1000 grain weight (GW), grain yield, biological yield and harvest index (HI) during both years was recorded in 20 cm apart plants with application of S-metolachlor + atrazine @ 740 g a.i. ha⁻¹ + 550 g a.i. ha⁻¹ + mesotrione and atrazine @ 687.5 g ha⁻¹ and lowest yield and yield traits were observed in 12 cm spaces plants with fully weeds. However, lowest weed density and weeds biomass was recorded in 12 cm apart plants with l weed free followed by application of S-metolachlor + atrazine @ 740 g a.i. ha⁻¹ + 550 g a.i. ha⁻¹ + mesotrione and atrazine @ 687.5 g ha⁻¹ and maximum weed density and weed biomass broad PD (12 cm) with weedy check. Additionally, maximum concentration of carbohydrate, protein and starch was also recorded in narrow PD (12 cm)) with application of S-metolachlor + atrazine @ 740 g a.i. ha⁻¹ + 550 g a.i. ha⁻¹ + mesotrione and atrazine @ 687.5 g and lowest concentration of carbohydrate, protein and starch was recorded in 12 cm spaced plants with weedy check. Therefore, combination of 20 cm spaced plants and application of S-metolachlor + atrazine @ 740 g a.i. ha⁻¹ + 550 g a.i. ha⁻¹ + mesotrione and atrazine @ 687 could be an promising approach to get better maize productivity in semi-arid regions.