Volume 6 > Part 3 > Year 1997 > Page 182 > Cruciferae > Rorippa

1. Rorippa nasturtium-aquaticum (L.) Hayekwfo-0000398907

Sched. Fl. Stir. Excicc. 3–4, 22. 1902; Jonsell in Fl. Mal. 1, 10: 555. 1988.

Accepted Name : Nasturtium officinale W.T.Aiton
R.Br., in Ait., Kew ed. 2, 4: 110. 1812; Hook.f. & Thoms. In Fl. Br. Ind. 1: 133. 1872; Kanjilal et al., Fl. Assam 1: 70. 1935; Back. & Back. F., Fl. Java 1: 191. 1963; Guo Rong-lin in Fl. Reipubl. Pop. Sin. 33: 311, plate 87, figs. 1–4. 1987.

Description : Glabrous perennial. Stems sturdy, procumbent at base then ascending, hollow, up to ca 100 cm. often rooting at lower nodes. Leaves dark green, clearly pinnate with 3–5 pairs of obovate-orbicular leaflets; upper leaves with short amplexicaul auricles. Petals white, ca 5 by 2 mm. Fruiting pedicels spreading, deflexed or ascending, ca 10 mm. Siliqua straight or curved, ca 15 by 2 mm. Seeds clearly arranged in 2 rows in each loculus; seeds reddish-brown, finely reticulate.

Thailand : [no herbarium specimens have been seen]

Distribution : Native in Europe and Asia, introduced and cultivated in many other parts of the world.

Ecology : In or alongside running fresh water.

Uses: Young shoots are eaten raw as a salad plant.

Notes: Watercress is quite widely grown in SE Asia, usually at higher altitudes; in the tropics it rarely flowers. Although no specimens from our area have been seen, the presence of the species in most adjoining countries suggest that it is also in Thailand. Many authors have regarded, or still regard, this species as in Nasturtium, but as for example Al-Shehbaz (1988) has pointed out when the world-wide situation is reviewed the case for its retention as an independent genus is untenable.