Title: Pharmacognostic studies of Siegesbeckia orientalis Linn.

Objective: To determine Pharmacognostical standards of Siegesbeckia orientalis Linn.

Material and Methods: The microscopical studies were performed by free hand as well as microtomed sections as per method prescribed by Johansen (1940). Microchemical tests for cell contents and cell wall structure were performed according to Trease and Evans (1978).Isolated elements were studied after maceration with chromic acid or by simple teasing of tissues. Behaviour of the powdered drug on treatment with different chemical reagents was noted as per Siddique et al. (1989). The photomicrographs pertaining to histological characters were taken with help of Olympus PM-6 (Japan).

Result: Morphological characters: herbaceous, stiff, erect, branched, and tinged with purple colour stem; leaves opposite, triangular ovate, acute or acuminate. Microscopy: stem of more or less circular outline with many narrow ridges and furrows. In the ridge portion, pericyclic sclerenchymatous cells in groups are present below the collenchyma. Growth of secondary xylem is comparatively more under the ridges. Pith is hollow; root with wide secondary xylem and 2-3 seriate medullary rays, pith is absent; leaf with protuberated midrib and smooth lamina, anomocytic stomata on lower epidermis, simple conical trichomes and gland cells on both epidermises. Conjoint, collateral vascular bundles at the regular interval in the central portion of lamina; petiole with one median large and two lateral smaller conjoint, collateral vascular bundles.

Conclusion: Diagnostic characteristics as observed during studies may be taken as pharmacopoeial standards for raw dug.

Published in: J. Econ. Taxon. Bot. Vol.24 No.1 PP. 161-170. (2000), pp 161-170.