Fig. 5. Timeline of female gametophyte, endosperm, and embryo development in Platanus racemosa during the course of this study (20 wk) in relation to pollination and fertilization. Figure Abbreviations: 2-N, two-nucleate female gametophyte; 4-N, four-nucleate female gametophyte; ENDO, endosperm; ES-fert, fertilized female gametophyte; free-N, free nuclear; GPT, female gametophyte; MSC, megasporocyte; MSP, megaspore; PEN, primary endosperm nucleus