Fruitlet development in the genus Potamogeton [Potamogetonaceae]

The development of the pericarp and its taxonomic value were studied in Potamogeton lucens, P. pusillus, P. crispus, P. pectinatus. The fruitlet of Potamogeton is drupaceous. Anatomical study and image analysis of developmental stages in the pericarps confirmed differences between species. The different degrees of pericarp sclerification, different positions of lignified cells in the pericarp, and numbers and types of pericarp layers have great diagnostic value. The vascular system of the Potamogeton flower and fruitlet, and the centrifugal direction of pericarp sclerification, do not have taxonomic significance within the genus Potamogeton. There are no significant differences in cell and layer size in Potamogeton fruitlets between the four species studied.