Articles

Ludwigia adscendens (L.) H. Hara

Ludwigia adscendens (L.) H. Hara

Family

Onagraceae

Synonyms

Jussiaea repens L., J. adscendens L.

Vernacular Names

Malaysia Tinggir bangau, inai pasir (Peninsular).
English Water primrose.
Indonesia Buang buang (Sumatran), krangking (Javanese), ganggeng landeuh (Sundanese).
Papua New Guinea Agidahano (Kutubu).
Philippines Sigang-dagat (Tagalog), gabi-gabi (Magindanao), tabagan (Ifugao).
Thailand Phak pot nam (Northern), phak phang phuai, phak phaeng phuai (Central).
Vietnam rau d[uwf]a n[uw][ows]c, rau d[uwf]a tr[aa]u, du long th[as]i.

Geographical Distributions

Ludwigia adscendens is a native of continental Asia, Sri Lanka, southern China, Japan, and also occurs throughout Southeast Asia to northern Australia. L. adscendens is introduced as a weed in tropical Africa.

 

Description

L. adscendens is a robust, prostrate or ascending herb, much branched and up to measure 60 cm tall. The floating stems are up to measure 4 m long, where the tops are above water, smooth, conspicuous aerophores on the nodes, spindle-shaped and white in colour.

The leaves are broadly oblong-elliptical in shape, with a size of measuring about 0.4-7 cm x 0.7-4 cm, narrowly wedge-shaped base, acute or obtuse apex, with 6-13 pair of veins and with a size of measure 1-2 cm long petiole.

The sepals are 5 in numbers, deltoid and they are measuring about 5-11 mm long. The 5 petals are obovate in shape, with a size of measuring 9-18 mm x 6-10 mm, rounded apex, creamy white and yellow in colour at the base. The stamens are 10 in numbers, with a size of measure 2.5 mm long filaments, single pollen and with 4-8 mm long style.

The capsule is measuring about 1.2-2.7 cm x 0.3-0.4 cm, normally smooth, thick-walled, irregularly dehiscent, conspicuously 10-ribbed and pale brown in colour.

The seeds are evident while the pedicel is 2.5-5.5 cm long. The seeds are uniseriate in each cell, ellipsoid in shape, flattened where each is firmly embedded in a cube of woody endocarp. The dark brown in colour of endocarp is fused to capsule wall.

 

Ecology / Cultivation

L. adscendens is very common in fresh water pools, swamps, fallow and planted rice fields, and in ditches, as well as occurs from sea-level up to 1600 m altitude. Plants growing under dry conditions have small, crowded leaves, are densely hairy and flower rarely.

 

Line Drawing / Photograph

Ludwigia_adscendens

References

  1. Plant Resources of South-East Asia No. 12 (2): Medicinal and poisonous plants 2.