Effectiveness of some herbicides and their application periods on maize (Zea mays L.) productivity

A field experiment was carried out in the fall agricultural season 2023-2024 in the village of Tal Hussein, affiliated to the Hawija District in Kirkuk Governorate, and after preparing the soil by plowing and fertilizing and according to recommendations, planting was carried out on 7/14/2023 with the RAYAL (NEVADA) variety that was obtained from the markets. Local. A two-factor experiment was implemented according to a randomized complete block design (R.C.B.D.), with three sectors, each sector containing (20) experimental units. The matches between the parameters were randomly distributed, and the area of the experimental unit was (4x4) m. Each experimental unit contains (5) lines, and the space between one line and another is 75 cm, between one plant and another is 15 cm, one experimental unit and another is 50 cm, and between one repeat and another is 1.5 m. The experiment was under a sprinkler irrigation system, and the following results were obtained: The herbicides had a clear significant effect on the total number of bushes for all periods, where the Rimisulfuron + Atrazine mixture gave the lowest average on the bush number characteristic and amounted to 7.58, which did not differ from the Rimisulfuron pesticide alone, as well as a decrease in the dry weight of the bush, whether due to individual factors or interaction between the two factors, as it was recorded Rimisulfuron pesticide had the lowest average dry weight after the weedless treatment, reaching 13.50 and 0.00, respectively. As for the yield characteristics and its components, pesticides had a significant effect on most traits, especially the number of grains. A head and a weight of 300 Grain and grain yield gave the highest averages for the Rimisulfuron pesticide treatments, reaching 17.46, 644.75, and 185.00, respectively, except for grain yield, where the Atrazine pesticide treatment was