A Critical Review of the Female Gametophyte in the Podostemaceae - Past, Present and Future Studies

Abstract

Anoverview of the habit and habitat of Podostemaceae is briefly discussed. Then,the paper attempts to review the past and present female gametophyte studies in the Podostemaceae. It trace the course and major achievements during the megasporogenesis, megagametogenesis and embryogenesis studies in the Podostemaceae. The evolutionary and functional significance of polarity during two-nucleate stage division of the megagametogenesis is discussed. Antipodal cell in the organized female gametophyte is discussed. Possible courses and causes of single fertilization and nucellar plasmodium organization are suggested. Then, provides and points out areas of special attention and limitations in the study of female gametophyte in future. Attempts are made to relate the ontogenies found in the family to plants with similar single fertilization phenomenon, for example Spinacia and Oenothera. Their embryological significances in the development of the female gametophyte in the angiosperms and gymnosperms are discussed.