The development of female gametophyte in hermaphrodite flowers of 'Pluk Mai Lie' papaya (Carica papaya L.)

Papaya (Carica papaya L.) is a fast-growing tropical fruit crop. It is a trioecious plant with male, female, and hermaphrodite type. Both female and hermaphrodite plants consist of female reproductive organs. The fruit shape, size, and numbers of seeds are largely influent by flower (particularly ovary) shape, fertilization, and numbers of fertile ovules. The female gametophyte was investigated during elongata type flower development. Papaya flowers at different stages were excised into thin sheets and examined immediately under the microscope 20× (Nikon YS 100). In addition, the resin-encapsulated flower specimen was also used to examine the development. The three development domains of papaya ovules were observed through 4 different stages (1-4). The similarity to Arabidopsis female gametophyte was observed and discussed.