A Note on the Floral Morphology of Aconitum heterophyllum Wall. (Ranunculaceae) - An Important Temperate Medicinal Plant

Abstract

Aconitum heterophyllum Wall. (Ranunculaceae), commonly known as Atish, is an important endangered (IUCN, 1993) temperate medicinal plant (Fig.1) distributed between 2400 and 4500 m amsl in temperate and alpine regions of the Himalaya. Distribution and morphology of this species has been extensively documented by various workers from time to time (Hooker and Thomson, 1872; Collett, 1902; Kirtikar& Basu 1975; Blatter, 1984; Polunin & Stainton, 1984; Prajapati et al., 2007 and Nautial et al., 2009). However, its floral description especially perianth as described by these workers appears to be incomplete. Its perianth has been described as (i) “Raceme many flowered, helmet shortly beaked……flowers more than 1 inch long, bright blue, greenish blue with purple veins. Helmet half as high as long†(Hooker & Thomson, 1872), (ii) “Flowers 1 in. long, dull green-blue with purple veins; helmet pointed in front, top rounded; lateral sepals as long as the helmet†(Collett, 1902), (iii) “sepals more or less blue or violet, rarely whitish, with dark conspicuous veins, finely pubescent or glabrous; upper sepal almost vavicular obliquely erect, shortly or obscurely beaked, 18-20 mm. high and as long from tip to base, widest (8-9 mm.) above the middle, lateral margin sinous, lateral sepal very oblique and broadly obovate with dark tips, 14-20 mm. long, 12-20 mm broad, not clawed; lower sepals elliptic, obtuse or subacute, 8-10 mm long; nectaries glabrous, extinguisher-shaped; claw erect, 16-18 mm. long, hood short (up to 4 mm.) and very wide, more or less gibbous above, lip very short and broad, obtusely 2-lobed or entire†(Kirtikar & Basu, 1975), (iv) “More than 1 inch long flower, dull green purple or dull green-blue with dark purple veins. Sepals 5, petal like, erect, the upper one (helmet) pointed in front, top rounded; lateral sepals as long as the helmet†(Blatter, 1984), (v) “Flowers 2.5-3 cm, usually in lax spike-like cluster with very variable bracts which are either small linear, small ovate, or large ovate and enclosing the lower part of the flower and fruit. hood rounded, broader than long†(Polunin & Stainton, 1984), (vi) “flowers are 2.5 cm long, helmet shaped, bright, blue or greenish-blue with pale veins†(Prajapati et al., 2007), vii) “Sepals more or less greenish blue with purplish veins, rarely whitish, glabrous, upper sepals almost navicular, obliquely erect and lateral sepals are very oblique and broadly ovate with dark tips†(Nautial et al., 2009).

Critical appraisal of these reports reveals that very little has been mentioned about its petals or their modification. This creates confusion especially when comparing it with other species of Aconitum L. Hence a need was felt to study its floral morphology discreetly. Flowers of this species were sourced from Rohtang area of district Kullu (2800 to 3000 m amsl), Himachal Pradesh, India.