Also found in: Dictionary, Medical, Wikipedia.
the maturation of the anthers and stigmas of flowers at different times. The importance of dichogamy for cross-pollination was first noted by A. T. Bolotov in 1780. In some flowers the anthers are the first to mature (protandry), and in others it is the stigma (protogyny). Dichogamy occurs not only in bisexual flowers but also in the unisexual flowers of monoecious and dioecious plants. Dichogamy is termed complete if the stigmas mature after the wilting of the stamens (or vice versa). More often dichogamy is incomplete, that is, the later maturing organs attain sexual maturity while the organs of the opposite sex have not lost their function. Protandry occurs in almost all the plants of the families Compositae and Umbelliferae. Protogyny is encountered more rarely, for example, in plants of the families Cruciferae, Rosaceae, and Ranunculaceae (anemones). The maturation of organs of different sexes at different times in cryptogams is also termed dichogamy.