Quantity and Quality of Commercially Reared Queens as Affected by Number and Distribution of Artificially Grafted Queen Cells Within Queen-Less Honey Bee Colonies in the Middle Delta Region, Egypt

This work was conducted throughout the queen rearing process using starter-finisher queen-less honey bee colonies to evaluate the impact of different numbers of grafted larval queen cups (24 and 48 grafted cups/colony), the level of bar they hung on it (top, middle, and bottom), and their positions they located on the bar (peripheral and middle) on the percentages of accepted queen cells and queen emergence, as well as the weight of emerged queens during three successive years (2021 to 2023). The number of grafted queen cups significantly influenced the studied traits in all years. The rates of acceptance and emergence were generally influenced by both bar level and cell position. The obtained values were significantly higher for the top (94.3 % and 97.7%) and middle (94.0 % and 92.0%) levels than in the bottom (89.4% and 87.0%) ones for the two characters, respectively. The middle position (93.6%) was positively higher than peripheral (90.8%) ones in case of accepted percent but not for rate of emergence (90.8%) and 88.9%, respectively. The weight of emerged queens was pronouncedly decreased in the bottom than both the top and middle levels and in the peripheral than middle position during study years. The general mean weights were 176.9, 172.8, and 162.8 mg/queen in the middle, top, and bottom levels of the bar and were 174.6 and 167.0 mg/queen for the middle and peripheral positions, respectively.