Effect of different flowering plants on the abundance of pollinators and natural enemies in the oilseed rape agrocenosis

The study aims to evaluate different flowering plants in terms of their attractiveness to pollinators and natural enemies, and to provide a list of species optimized for Bulgarian conditions. The field experiments were carried out in 2021-2023 in the region of Plovdiv. A total of 21 flowering plant species were tested. The number of pollinators (honey bees, bumble bees, etc.) attracted was highest on Phacelia tanacetifolia (3.3 ± 0.8 SE), Foeniculum vulgare (1.4 ± 0.5 SE), Borago officinalis (1.3 ± 0.4 SE), and Coriandrum sativum (1.2 ±0.3 SE) in 2022. The flowering plant species P. tanacetifolia, C. sativum, and B. officinalis were among the most attractive to natural enemies, mainly predators. In 2023 P. tanacetifolia (25.3 ±1.7 SE), Echium plantagineum (15.0 ±2.9 SE), Fagopirum esculentum (9.1 ± 1.3 SE), B. officinalis (7.4 ±1.9 SE) and C. sativum (3.5 ±0.9 SE) attracted the highest number of pollinators, while Anethum graveolens, Sinapis alba, and C. sativum were the most attractive plants for predators. Therefore, based on the observations in 2021-2023 three plant species lacy phacelia, borage, and coriander are highly recommended for inclusion in flower strip mixtures due to their strong appeal to various beneficial insects. Keywords: ecosystem service providers, flower stripes, natural enemies, oil seed rape, pests