Development of Intra-Ovarian Ovaries in Carica papaya L.1

Abstract

Abstract The occurrence of intra-ovarian ovaries in certain strains of Carica papaya L. is not uncommon. Approximately 150 hermaphroditic and 25 female ovaries from a hybrid progeny contained internal ovaries in stages of development ranging from thread-like appendages to round or elongated pistils of various sizes and shapes. A few were large enough to fill the entire seed cavity of the primary fruit and possessed their own cavities with non-viable seeds. Internal ovaries originate either from stimulated growth of rudimentary pistillate structures extending from the central axis of the receptacle or from placentae in positions normally occupied by ovules. The placenta may be in its normal parietal position or a single strand may become free, extended from the base of the primary ovary and support a mal-shaped secondary ovary as well as ovules. The occurrence of internal ovaries supports theories proposed by other investigators on the evolution of floral morphology in the papaya.