Influence of reared honey bees on the yield of Brassica juncea (L.) Czern. 1859: A case study from South Dinajpur District, West Bengal, India

Aim: This study investigated the role of honey bees in promoting agricultural sustainability through pollination, enhancing global crop productivity and food security. Methodology: Research was conducted across three agricultural sites: site with reared bees near MPH (within 200 m) highway; site with reared bees MP 3 km away from highway and site with wild, native bees (WP, 5 km away from highway). Observations focused on floral visitors, their foraging behaviour, plant fitness, and impact on fruit set. Results: Apis mellifera was found to be the most frequent visitor at MPH and MP site. However, A. dorsata was the most frequent visitor at WP site. Fields with reared bee hives (MPH and MP) had a higher count of floral visitors (5.42 at MPH; 4.5 at MP) compared to natural field (1.12 WP) without reared bee hives. The number of flowers visited per plant and plants visited in a bout was higher at MPH and MP as compared to WP. MPH and MP sites exhibited reduced flower handling time as compared to WP site. Siliqua (pod) per plant (83.05), seed number per siliqua (26.8) and seed weight (0.094 gm) were found highest at MP site (55.23 %, 44.47%, 17.5% higher compared to the WP site and 24.85%, 7.2%, 62.06% higher compared to MPH). Interpretation: Findings confirmed that reared bee pollination surpasses reliance on wild honey bees alone for effective pollination. The management of reared bees (A. mellifera) in agricultural practices would be an essential requirement for pollination services in mustard crops when the availability of wild, native bees is limited. Key words: Brassica juncea, Crop production, Reared honey bees, Wild pollinators