Ocimum gratissimum L.

M. Thulin et al. Flora of Somalia, Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Morphology General Habit

Perennial herb with a woody base, 0.4–2.5 m tall, with simple or rarely also some branched hairs

Morphology Leaves

Leaves petiolate; blade elliptic or ovate to broadly ovate, up to 30–150 × 20–85 mm, apex acute, acuminate or obtuse, base cuneate or attenuate, margin serrate

Morphology Reproductive morphology Inflorescences

Inflorescence lax or dense; bracts becoming downwards-pointing, deciduous after anthesis

Morphology Reproductive morphology Fruits Fruiting calyx

Fruiting calyx mostly ± downwards-pointing, 5–6 mm long, closed by the lower lobes being pressed against the upper lobe; upper lobe widest near the apex, 3–4 mm broad, narrowly cuneate at the base; lateral lobes subulate at apex; lower lobes connate to an emarginate lip

Morphology Reproductive morphology Flowers Corolla

Corolla 3–5 mm long, greenish, dull white or pale yellowish

Morphology Reproductive morphology Flowers Androecium Stamens

Anterior stamens c. 1 mm longer than the lower lip of the corolla

Morphology Reproductive morphology Fruits

Nutlets c. 1.5 × 1.5 mm, glabrous, minutely tuberculate, hardly producing mucilage when wet.

Note

Paton (1992) divided O. gratissimum into two subspecies. The description above refers to subsp. gratissimum, the only subspecies known from Somalia.

Lamiaceae (Labiatae), A.J. Paton, G. Bramley, O. Ryding, R.M. Polhill, Y.B. Harvey, M. Iwarsson, F. Willis, P.B. Phillipson, K. Balkwill, C.W. Lukhoba, D.F. Otieno, & R.M. Harley. Flora of Tropical East Africa. 2009

Type

Neotype, chosen by Paton, loc. cit. (1992) – specimen probably a later addition to Linnean Herbarium: cultivated in Uppsala, originally from India, Linnean Herbarium 749.2 (LINN!, neo.)

Morphology General Habit

Aromatic perennial herb 0.6–2.5 m tall

Morphology Stem

Stems erect, rounded-quadrangular, much branched, often striate, woody at base with epidermis often peeling in strips; glabrous or with scattered patent hairs below, becoming pubescent at nodes and on the inflorescence-axis, or pubescent with ± retrorse and patent hairs becoming hoary or tomentose on the inflorescence axis

Morphology Leaves

Leaf blades often darker above, elliptic or ovate to broadly ovate, 1.5–15 × 1–8.5 cm, serrate, apex obtuse, acute or acuminate, base cuneate or attenuate, indumentum of scattered short hairs mostly confined to veins beneath, or lower surface pubescent with upper glabrous or pubescent overall, sometimes tomentose beneath; petiole 5–30 mm long, glandular-punctate or not

Morphology Reproductive morphology Inflorescences

Inflorescence lax or dense (calyces of adjacent verticils touching or verticils ± 1 cm apart); bracts erect above forming a small green terminal coma, becoming downward-pointing and deciduous towards base, ovate or narrowly ovate, 3–12 × 1–7 mm, acuminate, sometimes cucullate; pedicels 3–4 mm long, spreading or ascending, slightly curved, ± flattened

Morphology Reproductive morphology Flowers Calyx

Calyx horizontal, ± downward-pointing or strongly reflexed against the inflorescence axis, 2–3 mm long at anthesis, pubescent, hoary or tomentose, with sessile glands or not; posterior lip large, rounded at tip, decurrent, teeth of anterior lip lanceolate, acuminate, teeth of lateral lobes bristle-pointed; fruiting calyx 6–8 mm long, tube closed, posterior lip accrescent, rounded or obtuse and wider at tip, decurrent, median lobes of anterior lip pressed against the posterior lip, teeth of the lateral lobes level with, or lower than, the underside of the anterior lip, sometimes spreading; indumentum pubescent, hoary or tomentose with sessile glands or not

Morphology Reproductive morphology Flowers Corolla

Corolla greeny or dull white or pale yellow, 3–4 mm long; tube straight, funnel-shaped, scarcely exceeding the calyx tube

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens exserted 1 mm from corolla, posterior with a flattened, hairy or subglabrous appendage near base

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary glabrous

Morphology Reproductive morphology Fruits

Nutlets brown, ± spherical, 1.5 mm in diameter, minutely tuberculate, producing a small amount of mucilage when wet

Figures

Fig 22: 7, 8, p 139

Note

(on the species as a whole). O. gratissimum forms a polymorphic complex in Africa. Subsp. iringense is easily recognised by its strongly reflexed fruiting calyces. Within subsp. gratissimum, var. macrophyllum is delimited from var. gratissimum by the combination of a lax inflorescence and sparse indumentum. This delimitation is supported by reference to Indian material where the discontinuity between the two varieties of subsp. gratissimum is upheld and the fact that var. macrophyllum has a limited geographical distribution in East Africa. Var. macrophyllum may have been introduced either from or to India and spread throughout Africa by cultivation. Cultivated Labiatae often tend to be glabrous as a result of selection by man. However, it is also possible that it may have arisen from var. gratissimum several times in response to environmental factors. Thus varietal rank is preferred to subspecific. See also Vieira, R., Grayer, R.J., Paton, A., and Simon, J.E. (2001) – Genetic diversity of Ocimum gratissimum L. based on volatile oil contents, flavonoids and RAPD markers. Biochemical Systematics and Ecology 29: 287–304. Forms exist in Uganda and Tanzania that correspond to var. macrophyllum in leaf and calyx indumentum and in having a lax inflorescence, but with a stem indumentum similar to var. gratissimum. These forms are similar to the type of O. gratissimum. There is no discontinuity that can separate these forms from the more densely hairy to tomentose forms previously referred to as O. urticifolium. Nor is there any morphological or ecological discontinuity separating forms with dense, wide, robust inflorescences (previously referred to as O. trichodon) from specimens with narrower inflorescences ( O. urticifolium). Thus within var. gratissimum inflorescence structure and stem, leaf and calyx indumentum form a continuum of variation. Two varieties based on the types of O. gratissimum and either O. urticifolium or O. trichodon could be recognised as there are large morphological differences between the extremes of this continuum. There are also supporting differences in leaf epidermis structure (Olowokudejo & Pereira-Shateolu in Phytomorphology 38: 147 (1988)) and chromosome number (Morton in J.L.S. 58: 231 (1962)). However, the practical difficulties of dividing and recognising the divisions of this continuum and the interbreeding between members of this complex reported by Khosta in J. Pl. Anat. Morphol. 3: 157 (1986) make this undesirable.

Bernal, R., Gradstein, S.R. & Celis, M. (eds.). 2015. Catálogo de plantas y líquenes de Colombia. Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Bogotá. http://catalogoplantasdecolombia.unal.edu.co

Distribution

Cultivada en Colombia; Alt. 300 - 1600 m.; Amazonia, Andes, Pacífico, Valle del Cauca.

Morphology General Habit

Hierba, subarbusto