Weed control and productivity of maize (Zea mays L.) in Malete, Kwara State of Nigeria

The need to determine the minimum application rates of commonly used herbicides in Malete and the Guinea savanna of Nigeria for effective weed control and higher grain yield of maize, triggered this study. Therefore, field trials were conducted at the Teaching and Research Farm of Kwara State University, Malete, to determine the weed control method that will be more effective in controlling weeds and give higher grain yield and cash returns in the production of maize. The experiment consisted of 9 treatments viz: primextra (metolachlor plus atrazine) + 2,4-D at 1.5 + 1.5 kg active ingredient (a.i.).ha⁻¹, primextra + 2,4-D at 2.0 + 2.0 kg a.i. ha⁻¹, primextra + 2,4-D at 2.5 + 2.5 kg ha⁻¹, primextra + nicosulfuron at 1.5 + 0.03 kg a.i. ha⁻¹, primextra + nicosulfuron at 2.0 + 0.05 kg a.i. ha⁻¹, primextra + niconsulfuron at 2.5 + 0.07 kg a.i. ha⁻¹, primextra at 1.5 kg a.i. ha⁻¹ + one Supplementary Hoe Weeding (SHW) at 6 Weeks After Sowing (WAS), two hand weeding at 3 and 6 Weeks After Sowing (WAS) and a weedy check. These treatments were laid out in randomised complete block design (RCBD) with three replicates. Data collected were subjected to analysis of variance using Statistical Analysis Software (SAS) package, after which means were separated using Duncan’s Multiple Range Test (DMRT). Results showed that treatment combinations of primextra + one SHW at 6 WAS, two hoe weeding at 3 and 6 WAS, primextra + 2,4-D at 2.0 + 2.0 kg a.i. ha⁻¹ and primextra + nicosulfuron at 2.0+0.05 kg a.i. ha⁻¹ gave effective weed control, higher grain yield and cash returns. Therefore, primextra at 1.5 kg a.i. ha⁻¹ + one SHW at 6 WAS, primextra +2,4-D at 2.0 + 2.0 kg a.i. ha⁻¹ and primextra + nicosulfuron at 2.0 + 0.05 kg a.i. ha⁻¹ are recommended to farmers as alternative to two hoe weeding at 3 and 6 WAS.