Structural and temporal modes of heterodichogamy and similar patterns across angiosperms

Abstract

Different kinds of synchronization of flowering, and of male and female function, have evolved in many angiosperms. The most complex patterns are heterodichogamy, pseudoheterodichogamy and duodichogamy. In this review, their occurrence across angiosperms is shown and the diversity in heterodichogamy and duodichogamy is outlined. Heterodichogamy is characterized by the occurrence of two temporally complementary genetic morphs, whereas in peudoheterodichogamy and duodichogamy only one morph occurs. In duodichogamy, the two phases result from alternating periods of several days of the same phase three or more times during a flowering season; however, they are of irregular length. In pseudoheterodichogamy, the two phases result from repeated flushes of flowering within individuals always with one or two flowerless days in between. In contrast to duodichogamy, the male and female phases alternate in a daily rhythm coordinated with the day-night rhythm. Heterodichogamy and similar patterns of synchronization are scattered across angiosperms; however, they are especially common in the Magnoliales, Laurales, Canellales, Zingiberales, Ranunculales, Trochodendrales, Fagales, Rosales, Malpighiales, Malvales, Sapindales, Caryophyllales and Apiales.