Weed infestation and productivity of oil poppy depending on the use of herbicide protection

The studies were conducted to study the effectiveness of using a mesotrione-based herbicide, 480 g/l (Egida, EC) by assessing its impact on crop infestation and the productivity of poppy plants in the forest-steppe conditions of the Middle Volga region. The work was carried out in 2023–2024 on the experimental field of the Federal Research Center for Bast Fiber Crops in the Penza Region. The object of the research was the Issera oil poppy variety. The herbicide used was Egida, EC (480 g/l mesotrione) with a consumption rate of 0.25 l/ha. The experimental design included the following options: control (no treatment); manual weeding; herbicide protection. The treatment was carried out in the phase of 6–8 true leaves of poppy plants. Weather conditions during the research years corresponded to insufficient moisture (GTC 0.55 and 0.83). In poppy crops, weeds were represented by late spring weeds (64.8 %), early spring weeds (23.7 %), winter weeds (7.2 %) and perennial weeds (4.3 %). In the variant with manual weeding, the total wet weight of weeds decreased after 20 days, in relation to the control, by 96.3 %, with the use of the preparation – by 80.5 %, before harvesting – by 91.5 and 88.7 %, respectively. The protective effect of the drug lasted until the end of the poppy growing season. Moreover, the efficiency of suppression of weed components (chamomile, sow thistle) was 91.6–100 %. Against the background of herbicide protection, the seed yield increased almost to the level of manual weeding by 0.33 and 0.38 t/ha compared to the control (0.98 t/ha). The productivity of poppy increased due to an increase in the elements of the crop structure: the number of capsules, the seed productivity of the plant, and the weight of 1000 seeds. When using manual weeding and herbicide, a positive trend towards increasing the oil content of poppy seeds was noted. The increase was 0.50 and 0.31 %, respectively, relative to the control.