Influences of Different Concentrations of Herbicides on the Growth and Yield of Maize as well as their Effects on the Associated Weeds in North-Western Nigeria

The field experiment was conducted in the dry season between December 2012 to April 2013 at Bakori, Bakori local government, Katsina (11033’N, 7036’E). The experiment consisted of 8 treatments levels which include 4 different formulations each; viz: ParaeForce(R) at 150ml / 20L and 200ml / 20L,AminoForce(R) at 100mL / 15L and 125mL / 15L applied a day before sowing and 4 weeks after sowing and a weedy control. The treatments were laid out in randomized complete block design (RCBD). The objective was to evaluate resistant weeds to herbicides (ParaeForce(R) and AminoForce(R)) and their effects on the growth and yield of maize. Result shows that 17 weed species from 11 families were encountered which include Cynodon dactylon, Cyperus rotundus, Doctylocterium aegyptium and Eleusine indica that shows signifcant (≥ 0.05) resistance to ParaeForce(R) + AminoForce(R) at 150mL / 20L followed by 100mL / 15L had 91.70, 87.12 and 49.15% weed control efficiencies at 4,8 and 16WAS. Sequential application of ParaeForce(R) + AminoForce(R) at 200ml/20L followed by 125mL/15L recorded significantly (≥0.05) high maize yield of (6.7kg) in all the three blocks and effective weed control with 86.28, 77.58 and 33.55% weed control efficiencies at 4, 8 and 16WAS. This study recommended the application of ParaeForce(R) and AminoForce(R) at 200mL/20L followed by 125mL/15L as an alternative way of reducing weed resistance to ParaeForce(R) + AminoForce(R) formulation and to improved performance of maize yield in the experimental site