Impact of Seeding Rate and Herbicides on Growth and Yield of Bread Wheat, Triticum aestivum and Associated Weeds

Abstract

The experiment was conducted in two locations during the 2022-2023 season, the first in the AL-Balwat village, and the second in the Hammam Al-Alil district, Nineveh Governorate, Iraq. The study aimed to determine the optimum concentration of chemical herbicides and the optimum seeding rate, and to assess their effects on growth traits, grain yield of bread wheat, and associated weed flora. The experiment comprised two factors: (i) seeding rates (120, 140, and 160 kg ha⁻¹) for the bread wheat cultivar Babylon-113, and (ii) different herbicides applied at varying concentrations, in addition to an untreated control (no herbicide). The measured parameters were: total weed density (weeds m⁻²), total weed dry biomass (g m⁻²), plant height (cm), flag leaf area (cm²), spike density (spikes m⁻²), number of grains per spike, 1000-grain weight (g), and grain yield (g m⁻²). The results obtained indicated that the herbicide Traxos R.C. and Discipline R.C. were the most efficient in reducing the weeds density and dry weight at both locations of Al-Balawat and Hammam Al-Alil, with a control efficiency that reached 58.75, 63.77, 60.53 and 57% for both herbicides and locations, respectively. The herbicide Discipline R.C. had a significant effect on the number of spikes and grain yield at both locations. The seeding rate of 160 kg/ha was better than the other seeding rates in reducing weeds and increasing yield. Grain yield at this seeding rate was higher by 24.05 and 24.90% than the yield of the seeding rate of 120 kg/ha at the two locations, respectively.

Keywords:

Herbicides, seeding rates, weeds, Discipline-OD, Traxos, Triticum aestivum L.