Maize (Zea mays L.) has high growth rate, produces large biomass and is highly susceptible to weed completion in its earlier growth stages till canopy closure. A Field experiment was conducted at Agronomy Research Farm of The University of Agriculture Peshawar, Pakistan during Kharif, 2016. Randomized complete block design (RCBD) with split plot arrangement was used keeping four replications. It was two factor study i.e. maize hybrids (DK-Garanon, Pioneer-3025, WS-666, and Pioneer-3164) allotted to main plots and potassium ratios (100% organic, 80% organic + 20% inorganic, 60% organic + 40% inorganic, 40% organic + 60% inorganic, 20% organic + 80% inorganic, 100% inorganic and control treatment) assigned to subplots. Potassium (K2O) was applied to field in such an arrangement that 100, 80, 60, 40, 20 and 0% K2O was acquired from the organic source (poultry manure) and the remaining was balanced form inorganic source (sulphate of potash) for supplying a total potassium of 80 kg ha-1. Results indicated that among maize hybrids, lowest weed fresh weight (271.60 g m-2), weed dry weight (80.53 g m-2) with highest emergence m-2 (7.74), 1000 grains weight (291.1 g), and harvest index (32.84%) was recorded for DK-Garanon hybrid whereas more grains ear-1 (496) and rows ear-1 (15) were recorded for Pioneer-3164. Highest weeds fresh (364.20 g m-2) and dry weight (114.4 g m-2) was registered in plots which received 100% K2O as organic source. Highest grains ear-1 (517), 1000 grains weight (300 g), and harvest index (36%) were recorded in plots where 40% K2O was applied from organic and 60% from inorganic source. It can be concluded from the experiment that application of 80 kg K2O ha-1 as 40% organic and 60% inorganic source to maize hybrid DK-Garanon resulted in better yield and yield components.
