Studies on the Character of Silkworm, Bombyx mori L., Which Bred from Double Copulation. (About the effect of copulating time and sperm activity in the double copulating)

동품종 교배와 이품종 교배를 교번한 이중교배의 차대잠 형질에 관한 연구(II) (교미시간과 정자의 활동성이 이중교배에 미치는 영향)

The ratio of form and character in the text generation of silkworms which were double copulated between home race copulation and hetero race copulation in crossing with two males of different races for female(double crossing) are different according to the copulating time, copulating order and sperm activities. But the general tendencies are as follows; 1. During two hour's double copulation, sufficiently ejaculating time, the fertilization percentage of hetero lace copulation are higher than that of homo race, but in case of double copulation with plain and normal marked silkworms showed opposite results. The fertilization percentage of homo race copulation are equal or higher compare with that of hetero race copulation. 2. The form and character of the next generation were largely effected by copulating order, so the primary copulating moths are more effected in the next generation than the secondary moths. 3. The active sperms were more fertilized than non-active sperms in the double copulation.