Natural History of Heterophylly in Nymphaea odorata ssp. tuberosa (Nymphaeaceae)

Abstract

Abstract Nymphaea odorata (American white water lily) is an aquatic plant that displays pronounced heterophylly, the appearance of different leaf forms on a single plant. Water lilies produce leaves that either float or are held above the water's surface. In this paper, we describe the natural history of water lily leaf forms and examine some of the factors that stimulate heterophylly. Over the course of a growing season, the predominant leaf form switches from surface leaves in the early season to aerial leaves in the midseason and then back to surface leaves at season's end. While many factors are known to contribute to heterophylly, our results suggest that changes in the light environment may be the controlling factor in this system.