Effect of some Elements of Integrated Weed Management on the Yield and Its Component of the Sunflower

Abstract

Abstract A field experiment was conducted in the field of the College of Agricultural Engineering Sciences - University of Baghdad during the spring season of 2021, aiming to study the effect of Datura root extract and the herbicide Trifluralin on the weeds accompanying the sunflower (Flami variety) and the crop yield and its components. The experiment was implemented based on the randomized complete block design (RCBD) in a split-plot arrangement with three replicates. The distances between the lines (60, 75, and 90) cm represented the main plots, and the subplots were the weed control treatments, involving 1-treatment of spray with Trifluralin at a rate of 2.4 L.ha-1(T1), 2- treatment of spray with Datura root extract at 18 l.ha-1 (T2), 3- treatment of spray with Trifluralin at 1.2 L.ha-1 + spray with Datura root extract at 9 L.ha-1 (T3), and 4- the weedy treatment (T4). The distance of 60 cm showed the lowest average density of the weeds accompanying the plant, recording 16.58 plants.m-2, and it recorded the highest values of the weed control percentage (63.12%) after 30 days of sequential planting, seed yield (5.242 t.ha-1), and oil yield (1.711 t.ha-1). The distance of 90 cm achieved the highest values of the disc diameter (18.66 cm), the number of seeds per disc (1232.0), and 1000 seed weight (89.95 g). Treatment T1 of spraying herbicide Trifluralin at a rate of 2.4 L.ha-1 achieved the lowest weed density (8.89 plants.m-2). It also recorded the highest values of the percentage of weed control (82.00%) after 30 days of planting, disc diameter (18.50 cm), number of seeds per disc (1289.0 seeds.disc-1), 1000- seeds weight (87.40 g), seed yield (5.744 t.ha-1), and oil yield (2.232 t.ha-1). The interaction between the two study factors significantly affected most of the traits under study. The interaction treatment between the distance of 60 cm and the treatment T1 achieved the lowest number of weeds, reaching 5.00 plants.m-2, the highest percentage of weed control, reaching 88.55% after 30 days of spray, and the highest seed yield of 6.553 t.ha-1. The interaction between the distance of 90 cm and the treatment T3 achieved high averages for the disc diameter (20.47 cm), number of seeds per disc (1466.1 seeds.disc-1), and 1000 seed weight (105.93 g). The results confirm the integration between the effect of the distance between the rows, the herbicide, and the extract in improving these traits.