Degree of sunflower crops weed infestation under various plant protection systems

Purpose. Determination of the most effective methods of protecting sunflower agrocenoses from weeds in order to increase seed yield and minimize harmful effects on the environment. Methods. During 2020-2022, weed contamination of crops of various sunflower hybrids was monitored under the conditions of traditional, Euro-lighting, Express and ecological plant protection systems. The species composition of weeds, the level of contamination and potential crop losses were assessed. Results. The results of the study showed significant variability in the level of weed infestation of crops depending on the type of sunflower hybrid, the characteristics of its development and the selected plant protection system. In particular, the species composition of weeds and the degree of contamination of agrocenoses of hybrids NK Neoma, NK Kondi and Sumiko HTS, which belong to different breeding groups, were established. It was proven that extreme climatic conditions, in particular elevated temperatures and moisture deficiency, significantly reduce the effectiveness of individual protection schemes, while at the same time increasing competition between the crop and weeds. Significant potential was recorded for further optimization of hybrid cultivation technologies by taking into account their genetic characteristics, adaptive properties and sensitivity to active substances used in protection systems. This approach allows better adaptation of technologies to specific conditions of the region and ensuring stable yields even under adverse environmental factors. Conclusions. Monitoring of contamination is the key to predicting crop losses and improving cultivation technologies. Further research should focus on the biological characteristics of new hybrids and their interaction with innovative protection systems.