Comparison of phosphorescent pigment dissemination for bee vectoring by Apis cerana and Apis mellifera on apple flowers

The bee vectoring technology, which utilizes the pollination behavior of bees to control pests and diseases of crops, has been demonstrated in various studies. Bee vectoring using honey bees has primarily focused on European honey bee, Apis mellifera. This study aims to compare the activity and dissemination efficiency of A. mellifera and A. cerana in apple flowers. To observe and track the dissemination process by honey bees, the microbial agent (Bacillus amyloliquefaciens MBI600 against fire blight) mixed with the phosphorescent pigment (MAMP) was used. A. cerana began foraging earlier (5:36 AM) and continued longer (13.39 h) than A. mellifera (6:27 AM and 12.45 h). As the temperature increased, A. cerana showed higher foraging activity than A. mellifera. At 9 a.m., A. mellifera spent more time on flowers (9.2 ± 5.4 sec) compared to A. cerana (7.0 ± 7.8 sec). The detection rate of phosphorescent pigment on apple flowers was 100 % for both species. On the stigma, the detection rates were similar, with A. mellifera at 98.0 % and A. cerana at 96.0 %. Both species showed 100 % detection rates on the anther. After two supplies of MAMP, A. mellifera delivered an average of 6.6 µg of phosphorescent pigment per flower, while A. cerana delivered 4.9 µg. However, there was no significant difference between the two species. While it is known that one A. cerana worker delivers a smaller amount on its body than A. mellifera, the amount delivered to a single flower during the release period of the honey bees was similar between the two species. This is presumed to result from differences in their foraging behaviors and activities. As a result, A. cerana could be an alternative vectoring bee in small-scale orchards. It could also be used in orchard environments where the use of A. mellifera is restricted, such as under low-temperature conditions.