Control of segetal vegetation in the agrocenosis of common buckwheat

The aim of the study was to determine the effectiveness of herbicides in controlling segetal vegetation in the agrocenosis of common buckwheat (Fagopyrum esculentum Moench.) while considering their influence on crop condition and yield formation. The methodology involved a field experiment conducted at the Educational and Research Field of Polissia National University during 2021-2025, which included five variants of herbicide control, namely the use of the graminicide Norvel Extra alone and in combination with the preparations Horizon, Tsukron+, and Helianthex. Herbicide effectiveness was assessed through quantitative weed composition at three observation periods, and yield was measured according to standard agronomic procedures with an untreated control. The study found that the structure of weed infestation was dominated by grass species, accounting for 77.2% of the total weed population. The application of Norvel Extra alone ensured a technical efficiency of 77.1%, whereas its combinations with Horizon, Tsukron+, and Helianthex provided weed control ranging from 88.5% to 95.5%. A strong correlation was observed between yield preservation and weed suppression, with yield retention levels of 23.5-42.6% compared to the control. The results indicated that the highest performance was achieved when Tsukron+ and Helianthex were combined with the graminicide, due to their selective activity against both grass and broadleaf species. The practical value of the study lies in the potential use of its results by agronomists, crop consultants, and agricultural producers to optimise buckwheat herbicide management systems and improve crop productivity under Forest-Steppe conditions in Ukraine