FLORAL BIOLOGY AND BREEDING SYSTEM OF STERCULIA CHICHA ST. HIL. (STERCULIACEAE)

Summary The neotropical, monoecious, forest species Sterculia chicha has been shown to have flowers which are adapted for pollination by Diptera, such as medium‐sized species of the sapromyo‐philous genera Acroglossa, Cachliomya, Gaemnochaetopsis, Ornidia and Parasarcnphaga. Controlled pollination experiments show that the species is self‐incompatible. The fact that pollen tube growth proceeds to the ovule following both compatible and incompatible pollinations suggests that the incompatibility mechanism is based on the non‐fusion of gametes in the embryo sac, as in the Theohroma‐type, originally known only in the related Theobroma cacao.