Sisymbrium orientale L.

Sisymbrium species are annual, biennial or perennial herbs, glabrous or pubescent with simple trichomes, not scapose. Rootstocks taproot. Stem usually erect, subprostrate or decumbent, ascending, simple or branched distally. Basal leaves rosulate or not, obovate-lanceolate to oblong in outline, margin lyrate pinnatifid to pinnatisect, rarely entire, apex acuminate, petiolate, cauline leaves gradually smaller, similar to basal, petiole short to sessile. Inflorescence racemes, many flowered, considerably elongated in fruit, ebracteate, rarely bracteate. Flowers bisexual, yellow, white, pink, purple, pedicel erect or reflexed, divaricate, slender or thick, ascending, sepals 4, erect or spreading, linear ovate-oblong, margin membranous, inner lateral pair base sometimes subsaccate, petals 4, obovate-oblanceolate to spathulate, margins entire, apex obtuse or emarginate, claw distinct, usually almost equal or slightly longer than sepals. Stamens 6 rarely 4, tetradynamous, filaments not dilated near the base, anthers ovate-oblong, apex obtuse rarely apiculate, nectar glands 4 confluent, usually subtending the bases of stamens, median glands present. Ovary superior, linear subcylindrical, bicarpellary, ovules 10-160. Fruit siliqua, dehiscent, linear cylindrical, sessile or rarely shortly stipitate, terete or latiseptate, smooth or torulose, valves prominent midvein and obscure marginal veins, valves chartaceous to leathery, replum rounded, septum complete, style subclavate or cylindric, stigma capitate, bilobed, lobes not decurrent. Seeds uniseriate, brown, plump, oblong-ovoid, not winged, minutely reticulate, not mucilaginous when soaked, cotyledons obliquely incumbent.

Sisymbrium species flowers are complete, bisexual, i.e., with functional male (androecium) and female (gynoecium), including stamens, carpels and ovary. Pollination is entomophilous i.e., by insects, or cleistogamy i.e., by self or allogamy i.e., by cross pollination. Flowering/Fruiting: April—August.

Seeds may be dispersed by autochory i.e., self dispersal, anemochory i.e., wind dispersal, zoochory i.e., dispersal by birds or animals, anthropochory i.e., dispersal by humans.

Annual herbs, glabrous or pubescent with simple trichomes, about 20-75 cm tall, not scapose. Rootstocks taproot. Stem erect, ascending, simple or branched distally above, usually pubescent near the base. Basal leaves in rosulate, obovate-oblanceolate to broadly oblanceolate in outline, about 3-8 x 2-4 cm across, margins runcinate-pinnatipartite to subentire, with 2-5 linear lanceolate-oblong lobes on each side, terminal lobe slightly bigger than the lateral ones lobe margins coarsely dentate to entire, midrib impressed above and prominent beneath, glabrous above and pubescent beneath, petiole about 1-5 cm long, cauline leaves gradually smaller, similar to basal with 1-2 lobes on each side, lateral lobes linear lanceolate, terminal lobe usually hastate, petiole short to subsessile. Inflorescence racemes, 15-20 flowered, elongated in fruit, ebracteate. Flowers bisexual, yellow, pedicel erect, divaricate, slender later almost as thick as the fruit, pubescent, about 4-7 mm long, sepals 4, erect or spreading, linear oblong, margin membranous, inner lateral pair base sometimes subsaccate, pubescent outside, yellowish, about 4-5.5 x 1-2 mm across, petals 4, spathulate, margins entire, apex obtuse or subemarginate, about 6-9 x 2.5-4 mm across, claw distinct, usually almost sub equal to sepals. Stamens 6, tetradynamous, filaments not dilated near the base, about 5-8 mm long, anthers ovate-oblong, apex obtuse, about 1-2 mm long. Ovary superior, linear subcylindrical, bicarpellary, ovules 60-100. Fruit siliqua, dehiscent, linear subcylindrical, about 60-100 x 1-1.5 mm across, terete, erect or slightly curved, valves with prominent midvein, valves glabrous or pubescent, septum complete, style subclavate, about 1-3 mm long, stigma capitate, bilobed. Seeds 40-50 in each locule, brown, plump, ellipsoid or narrow oblong-ovoid, about 1-1.5 mm long, not winged, minutely reticulate, not mucilaginous when soaked, cotyledons obliquely incumbent.

Sisymbrium species are susceptible to various insect pests, virus, mildews and moulds.

Rocky places, crevices and waste places, altitude 2700-3200 m.

Not evaluated (IUCN).

Used in folk medicine.