khubakalam :
Morphology:
Annual or biennial herbs, glabrous or sparsely pubescent near the base with simple trichomes, about 15-80 cm tall, not scapose. Rootstocks taproot. Stem erect, ascending, simple or divaricately branched, pubescent at the base and glabrous above. Basal leaves in rosulate or not, obovate-oblanceolate to oblong in outline, about 3-15 x 1.5-6 cm across, margins runcinate-pinnatifid to pinnatipartite, with 3-7 linear lanceolate-oblong lobes on each side, terminal lobe slightly bigger than the lateral ones, lobe margins dentate or lobed, pubescent on the margins and beneath, petiole about 1-4 cm long, cauline leaves gradually smaller, similar to basal but linear, margins 1-3 lobed or entire, petiole short to subsessile. Inflorescence raceme corymbs, 30-80 flowered, elongated in fruit, up to 25 cm long in fruit, ebracteate. Flowers bisexual, yellow, pedicel erect or reflexed, divaricate, slender, much narrower than the fruit, about 6-12 mm long, sepals 4, erect or spreading, linear oblong, cucullate, margin membranous, inner lateral pair base sometimes subsaccate, about 2-2.5 mm long, petals 4, obovate-obovate, margins entire, apex obtuse, about 2.5-3.5 x 1-1.5 mm across, claw distinct, suequalling or slightly shorter than sepals. Stamens 6, tetradynamous, filaments yellowish, not dilated near the base, about 2-4 mm long, anthers ovate-oblong, apex obtuse, about 0.5-0.8 mm long, nectar glands 4 confluent, usually subtending the bases of stamens, median glands present. Ovary superior, linear subcylindrical, bicarpellary, ovules 40-90. Fruit siliqua, dehiscent, linear subcylindrical, about 30-50 x 0.8-1.2 mm across, younger fruits overtopping the flowers, terete, erect or slightly curved inwards, valves prominent midvein, valves glabrous to torulose, replum rounded, septum complete, style subclavate or subelongate, about 0.3-0.5 mm long, stigma capitate, bilobed. Seeds uniseriate, brown, plump, oblong-ovoid, about 0.8-1 mm long, not winged, minutely reticulate, not mucilaginous when soaked, cotyledons obliquely incumbent.
Histology:
T.S. of seed shows seed coat with six layers, outermost a single layer of epidermis of rectangular, flattened and thin walled cells ranging from 30 to 50 n in length containing colourless, concentrically striated mucilage; a two-cell deep layer of parenchymatous cells, a single row of sclerenchymatous cells with their radial and inner tangential walls thickened, a single-cell layer of pigment, a single cell layer of aleurone grains, followed by crushed parenchymatous cells; cotyledons contain aleurone grains and oil globules; embryo folded; starch absent.
