SEM4, CC8, Unit 7 Family: Dr. Subhadip Chakraborty

Characters of Nymphaeaceae: Aquatic herbs with large and peltate ; hermaphrodite, hypogynous to epigynous; segments many, spiral, gradually passing from to and petals to , stamens many; carpels many in pits of the torus or confluent with it, ovules disposed on lamellate or parietal placentae; a spongy berry or an etaerio of achene or nuts sunken in the pits of a turbinate torus.

A. Vegetative characters: Habit: The are fresh water aquatic herbs, either annual or perennial, with coloured or watery latex.

Root: Adventitious, slender, attached to -stocks ().

Stem: Rhizome, rooted in the mud or at the bottom of shallow lake or pond, branched, erect () or creeping ().

Leaf: Alternate, simple, long petioled, floating or immersed; large, broad lamina; sometimes dimorphic (Cabomba), the leaves of Victoria regia, the royal water-lily of South America, are 60-180 cm. in diameter with upturned margins and prickly below.

B. Floral characters: Inflorescence: Solitary terminal or axillary on long leafless scape.

Flower: Large, showy, hermaphrodite, hypogynous to perigynous, acyclic, hemicyclic or rarely cyclic, thalamus freshy, cup shaped, surrounding the carpels, with perianth and stamens adnate to it, fragrant.

Calyx: Sepals 3 in Brasenia; six to indefinite, free, gradual transition from sepals to petals and petals to stamens.

Corolla: Petals 3 to 5 or many, polypetalous, large and attractive, inner petals form petaloid staminodia.

Androecium: Stamens 6 to indefinite, free, adnate to thalamus, spirally arranged, anthers, bithecous, introrse, filament foliaceous, extended as sterile appendages beyond the anther sac.

Gynoecium: Carpels 3 to many, apocarpous (Cabomboideae and Nelumboideae) or syncarpous (Nymphaeoideae), superior (Nelumbium) or inferior (Vitoria), Unilocular or multilocular, one to many ovules on lamellate or parietal placenta; style short; stigmas as many as carpels, free or united, radiating, often with appendages.

Fruit: Spongy berry (Nymphaea), an etaerio of achene () or follicle (Cabomba).

Seed: Often arillate, endospermic or non-endospermic, embryo straight; perisperm present.

Pollination: Entomophilous, flowers protogynous; flowers of Euryale are cleistogamous and self-pollinated.

Floral formula:

Distribution of Nymphaeaceae: It is commonly called “water-lily family”. The family consists of 8 genera and 100 species according to Rendle. It is almost cosmopolitan in distribution except in very cold regions.

Economic Importance of Nymphaeaceae: The family is not of great economic importance.

1. Food: The seeds of Nymphaea, Nelumbium are edible due to stored starch. The of Nelumbo pentapetala (H. Bhen) are used as vegetable.

2. Medicine: The of are recommended as cardiac tonic and also in treatment of liver diseases. The dried and powdered rhizomes of Nelumbo nucifera are used to cure piles.

The rhizomes of Nymphaea are used in dysentry.

3. Ornamental: The plants of Nymphaeaceae are important for their brilliantly coloured flowers. The Nymphaea, etc., are cultivated in gardens.

Division of the family and chief genera: On the basis of the construction of floral parts the family has been divided into three sub-families: Sub family I. Cabomboideae: Flowers cyclic, trimerous and hypogynous.

Perianth segments in two whorls of 3 each, outer one forming sepals and inner petals. Stamens 6. Carpels, 3, free. e.g. Cabomba and Brasenia. Sub-family II. Nelumboideae: Flowers acyclic and hypogynous. Perianth-segments indefinite, outer whorl of 5 sepals. Stamens indefinite. Carpels many, free e.g. Nelumbo (Nelumbium).

Sub-family III. Nymphaeaoideae: Flowers hypogynous, perigynous or epigynous. Perianth- segments in indefinite whorls, of 4-5 sepals in each whorl. Stamens indefinite, carpels many, united, e.g. Nymphaea, Nuphar, Victoria, Euryale.