抄録
In nature, the dioecious plant Cannabis sativa usually opens its flowers on short days and cross-pollination occurs. When subjected to short day conditions, female-only plants change to intersexual plants, which have both female and male flowers, and progeny is produced by self-pollination. On the other hand, when male-only plants are exposed to short day conditions, intersexual plants are never observed. When female and male plants were mixed in a greenhouse under short days, developing male flowers on intersexual plants fell off and cross-pollination occurresd. In order to elucidate the mechanism for this, physiological experiments were attempted. When female and bagged male plants were mixed under short day conditions, the male flowers on intersexual plants did not fall off and self-pollination occurred. Moreover, when intersexual plants were artificially pollinated with pollen from male plants, developing male flowers on the intersexual plants fell off. In contrast to the mating of the pure line fellow, the male flower on the intersexual plants did not fall. These results demonstrate that the shedding of male flowers by intersexual plants is associated with transmission of a signal involving the products of pollination and the genetic factor.
