Inbreeding and selection response in a small population of honeybee under incomplete reproductive isolation

Assuming a small population of honeybee with incomplete reproductive isolation, we developed theories to predict response to selection and inbreeding coefficient. The theories were applied to a selection program with a scale applicable to beekeepers in Japan. Numerical computation showed that even under an incomplete reproductive isolation, a remarkable genetic gain could be achieved if more than 90% of drones can be isolated. It was also shown that a small amount of introgression of drones from outside populations would effectively suppress the increase of inbreeding coefficient.