Herbicides and Effective Weed Control in Maize (Zea mays L.)

Abstract

Abstract A field experiment was carried out in the experimental field of the College of Agricultural Engineering Sciences / Saladin University (Erbil Governorate) during the fall season of 2023, to evaluate the productivity of the yellow maize crop and control of weeds associated with it using two herbicides and their mixture under different planting distances. The experiment was applied according to a randomized complete block design in a split-plot arrangement with three replicates. Plant densities (66,600, 57,100, and 50,000 plants.ha-1) were assigned at the main plots, and control treatments (Nicosulfuron @ 48 g.ha-1, Metribuzin @ 400 g.ha-1, Nicosulfuron + Metribuzine @ 48+ 400 g.ha-1, weedy, and free weed) were assigned at sub-plots. The results showed that Nicosulfuron was superior in giving the best results. The herbicide gave the lowest average weed density after 30 and 60 days, the highest control rate, the highest number of grains per ear, the highest number of rows per ear, and the highest grain yield by (4.08 and 6.26 plant.m-2, 84.98%, 606.3 grains, 16.97 rows, and 5.93 tons.ha-1, respectively). Compared with the comparison equation, which gave the lowest weed density after 30 and 60 days, the lowest weed control rate, the lowest number of grains per ear, the lowest number of rows per ear, the lowest weight of 500 grains, and the lowest grain yield tons.ha-1. Furthermore, the results also showed that the plant density of 66,600 plants.ha-1 exceeded, as it gave the lowest average weed density after 30 and 60 days and the highest grain yield (6.22 and 9.04 plant.m-2 and 5.75 tons.ha-1, respectively). Moreover, the plant density of 57,100 plants.ha-1 also gave the highest average for the number of rows and the number of grains per ear, amounting to 15.83 rows and 5.39 grains, respectively, compared to the low density (50,000 plants.ha-1), which gave the lowest averages for all traits, but it exceeded by giving the highest weight of 500 grains of (119.92 g) only. However, the interaction had a significant effect on all the traits, as the herbicide treatment and the weed-free treatment showed a positive behavior by reducing the weed density, increasing the control rate, and increasing the components of yield and grain yield, according to the different plant densities used.