On the orientation of carpel sutures in Fabaceae

Angiosperms are the group with the greatest diversity in the current vegetation and ecosystem. Many taxa in angiosperms are closely related to the well-being of the human beings. The frequently seen Fabaceae are the focus of botanical studies due to their important economic value. Although many morphological questions (especially those of Fabaceae) have been well answered after long time efforts, the orientation of the carpel sutures in Fabaceae remains puzzling. Monocarpellate has been taken as a feature of Fabaceae, and its suture is interpreted as oriented ventrally. This interpretation is coherent to the classical understanding of magnoliaceous carpels. However, besides monocarpellate, many gynoecia in Fabaceae are multicarpellate and the orientation of the carpels varies. What is the relationship among these gynoecia and carpels? The answers to these questions are hinged with our thorough comprehension of morphology and evolution of angiosperms. We wish more botanists to join our enquiring of these questions.