Journal of Threatened Taxa | www.threatenedtaxa.org | 26 October 2023 | 15(10): 24086–24091

ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print)

https://doi.org/10.11609/jott.8544.15.10.24086-24091

#8544 | Received 21 May 2023 | Final received 10 September 2023 | Finally accepted 01 October 2023

Ocimum gratissimum L. ssp. gratissimum var. macrophyllum Briq. (Lamiaceae: Nepetoideae: Ocimeae) a new record from northeastern India

Mamita Kalita¹, Nilakshee Devi^{2 &} Diganta Narzary³

^1,2,3 Department of Botany, Gauhati University, Jalukbari, Guwahati, Assam 781014, India.

¹mamita.bot@gmail.com (corresponding author), ²devinilakshee@gmail.com, ³d_narzary@gauhati.ac.in

Editor: K. Haridasan, Palakkad, Kerala, India. Date of publication: 26 October 2023 (online & print)

Citation: Kalita, M., N. Devi & D. Narzary (2023). Ocimum gratissimum L. ssp. gratissimum var. macrophyllum Briq. (Lamiaceae: Nepetoideae: Ocimeae) a new record from northeastern India. Journal of Threatened Taxa 15(10): 24086–24091. https://doi.org/10.11609/jott.8544.15.10.24086-24091

Copyright: © Kalita et al. 2023. Creative Commons Attribution 4.0 International License. JoTT allows unrestricted use, reproduction, and distribution of this article in any medium by providing adequate credit to the author(s) and the source of publication.

Funding: None.

Competing interests: The authors declare no competing interests.

Author details: MAMITA KALITA specializes in angiosperm taxonomy and currently working as assistant professor in the Department of Botany, Digboi College, Assam. She is pursuing her doctoral degree under the guidance of Prof. Nilakshee Devi and Dr. Diganta Narzary from the Department of Botany, Gauhati University, Guwahati, Assam. PROF. NILAKSHEE DEVI is a full time faculty in the Department of Botany, Gauhati University, Guwahati, Assam. She has 15 years of teaching experience and her research expertise includes plant taxonomy, palynology, ethnobotany, medicinal plants and phytochemistry. DR. DIGANTA NARZARY is a full time associate professor in the Department of Botany, Gauhati University, Guwahati, Assam. He is actively teaching botany and microbiology subjects and doing research in the area of plant and microbial systematics, metagenomics, ethnic food microbiology and other applied microbiology aspects.

Author contributions: ND and DN conceptualized and supervised the research work; MK did the field and laboratory works, and drafted the manuscript. ND and DN finalized the manuscript, and MK communicated to the Journal.

Acknowledgements: The authors are thankful to herbarium curators/officers of herbaria, such as ASSAM, ARUN, CAL, and GUBH.

Abstract: The genus Ocimum means fragrant-lipped, characterized by the presence of the upper lobe of the calyx, which is large and decurrent. Ocimum gratissimum L. is conventionally known as Clove Basil due to its foliage which smells like cloves. The present study reports the extant distribution of O. gratissimum L. ssp. gratissimum var. macrophyllum Briq. across northeastern India. It is a new distribution record for the flora of Assam and northeastern India. A comprehensive description along with photographs, taxonomic notes, and diagnostic keys has been provided to aid identification.

Keywords: Assam, distribution, flora, keys, lipped, taxonomy.

Introduction

Commonly known as ‘Tulsi’ in Hindi and ‘Toolakhi’ in Assamese, ‘Basil’ (Empress of all herbs) descended from the greek word ‘Basileus’ which means royal, and ‘Ocimum’ from ‘okimon’ which purports an aromatic herb. Ocimum L. is chiefly an ‘East Indian’ genus (Bentham 1832). The primary centre of origin is Africa, Tropical Asia, and Central and South America, while India is the secondary centre (Pushpangadan & Sobti 1982). According to APG IV, Ocimum gratissimum is a member of the tribe Ocimeae Dumort., subfamily Nepetoideae Burnett in the mint family Lamiaceae Martinov (Stevens 2001 onwards). The specific epithet ‘gratissimum’ explains an exaggerated expression of pleasantness due to the aroma of the species. The species have a more substantial degree of fragrance than other Ocimum L. species (Roxburgh 1832). O. gratissimum has two accepted sub-specific taxa, O. gratissimum ssp. gratissimum and O. gratissimum ssp. iringense Ayob. ex Paton. The latter subspecies is confined to Tanzania, while ssp. gratissimum is native to the tropical and sub-tropical old world. The variety macrophyllum was first acknowledged by Briquet (1894) affirming the distribution of var. macrophyllum in India Orientalis. According to Ryding (2000), var. macrophyllum is widespread in the tropics from India to western Africa. The var. macrophyllum got introduced from or to India and later disseminated through African cultivation. The variety was acknowledged by Paton (1992) while investigating Ocimum L. in Africa. He found a few forms of O. gratissimum in Uganda and Tanzania, corresponding to var. macrophyllum in having lax inflorescence, calyx, and leaf indumentum. The distinction of the varieties based on morphological characteristics conceals the facts acquired from genetic and secondary product variation. Such high degree variation is found in var. gratissimum against var. macrophyllum (Vieira et al. 2001). The var. macrophyllum is recognized by glabrous or pubescent leaves (hairs scattered over lower nerves) and hairy inflorescence (Albuquerque & Andrade 1998). While revising the tribe Ocimeae Dumort., Suddee et al. (2005) distinguished both varieties of O. gratissimum ssp. gratissimum (var. gratissimum and var. macrophyllum) and their distribution from India. The var. macrophyllum might have arisen from var. gratissimum in response to environmental constrain (Paton et al. 2009).

The Indian subcontinent is acknowledged by ssp. gratissimum. The var. macrophyllum is treated within ssp. gratissimum and reported earlier from different states of India, except Himachal Pradesh, Jammu & Kashmir, Uttarakhand, and northeastern India. In the present study, the variety macrophyllum is being reported for the first time from Assam.

Materials and Methods

The specimens of the var. macrophyllum were collected from Jorhat district of Assam during our field survey conducted in 2019–22. Field photographs and GPS locations were recorded using a digital camera. The micro-morphological features were investigated on living specimens using a Labomed CZM4 stereo zoom binocular microscope. Further, photo plates were prepared using Adobe Photoshop 7.0. The variety was identified by consulting regional and national herbaria, such as ARUN, ASSAM, CAL, and GUBH, and through relevant literature (Floras, Journals, Revisions, and Synopsis). The microfilms of herbarium specimens from online databases BSI-IVH, G, JSTOR, KEW, LINN, MNHN, MO, and NY were also consulted for identification. The new distributional record of the variety was confirmed through research articles and literary works such as checklist, flora, and floristic records of northeastern India, along with physical verification of herbarium records held by ARUN, ASSAM, CAL, and GUBH. The morphological affirmations were correlated with lectotype G00018935 and photographs acquired from MNHN (Image 1). The common and vernacular names are given in English (E), Hindi (H), and Assamese (A).

Taxonomic treatment

Ocimum gratissimum L. ssp. gratissimum var. macrophyllum Briq.

Bull. Herb. Boissier 2: 120.1894; Paton in Kew Bulletin. 47: 417.1992; Paton, Harley & Harley in Holm & Hiltunen, Basil: Ocimum. 25.1999; Ryding in Fl. Somalia 3: 341.2006.

Type: Lectotype (LT): G00018935, Madagascar, Bourbon, Boivin L.H. LT present in Conservatoire et Jardin botaniques de la Ville de Genève (G) and photo of type in K!

Description: Perennial shrubs, 1.5–2 m tall; Stem erect, much branched, woody at the base, rounded quadrangular, glabrous; Leaves 6–12 × 4.5–7 cm in size, serrate, surface smooth, hairs restricted to veins beneath, apex acuminate, multicostate divergent reticulate venation; Petiole 1.5–4 cm long, slender; Inflorescence 15–22 cm long, lax, axis glabrescent, verticils 0.8–1.2 cm apart; Bracts 3–4 × 1.8–2.5 mm, green, ovate with broad base, caducous, apex acute, base cordate, sub sessile or sessile, margin ciliate, pubescent on both sides; Pedicels 3–3.5 mm long, pubescent, spreading, recurved; Calyx 2–3.2 × 2–3.5 mm, slightly downwards pointing against the inflorescence axis, green, slightly purplish at tips, posterior lip rounded, wider at tip, acute apex, decurrent on tube, anterior lip shorter than posterior, two hooked lateral curved teeth (uncinate lip) slightly lower than the two median teeth, median lobes of anterior lip pressed against posterior one in fruiting calyx, throat closed, tube with patent hairs or without; Corolla 4–5.5 × 2–3 mm, light pastel yellow, barely exceeding the calyx, lobes obscurely crenate, minute hairs at back, posterior lip oblong and comparatively shorter than anterior lip, lobes are equal in length, anterior lip boat shaped, tube straight, puberulous outside, glabrous inside; Stamens 4.5–5 mm, occasionally equal in length with anterior stamens, posterior pair having tufts of hairs at base (barbate filament base); Gynoecium 6.5–8 mm, two equal lobes, curled bifid stigma, ovary more or less globose; Nutlets 1.8–2.2 × 1.5–2 mm, ivory in colour, brown at maturity, sub globose, minutely tuberculate, producing mucilage when wet (Image 2).

Flowering and Fruiting: It was observed in July.

Common names: African Basil, Clove Basil, East Indian Basil, Russian Basil, Shrubby Basil, Tree Basil, Wild Basil, Tea Bush (E), Ban Tulsi, Jangli Tulsi, Vriadha Tulsi, Mali Tulsi, Ram Toolsee (H) and Ram toolakhi (A).

Key to the Infra-specifics of Ocimum gratissimum L.

1. Flower verticils 1–1.5 cm apart, not strongly reflexed towards the inflorescence axis; flowering and fruiting calyces recurved .................................. .............................. O. gratissimum ssp. gratissimum

2. Inflorescence 10–13 cm long, dense, axis softly pubescent; leaves pubescent on both sides; calyx horizontal or slightly upward pointing ……............... ............................... O. gratissimum var. gratissimum

2. Inflorescence 15–22 cm long, lax, axis glabrescent; hairs restricted to veins beneath; calyx downward pointing ….…..... O. gratissimum var. macrophyllum

1. Flower verticils 0.7–1.0 cm apart, strongly reflexed towards the inflorescence axis; flowering and fruiting calyces decurved ...................................................................... O. gratissimum ssp. iringense

Specimen examined

Africa: Réunion. Boivin, L.H. -21.1216E , 55.5380S. O. gratissimum L. var. macrophyllum Briq. Herbarium Genavense (G), Lectotype (G00018935!). Madagascar: L.J. Dorr, 24.ii.1985. Original material? of O. gratissimum var. macrophyllum Briq. MO-694055! Coll.No.3779. Verified by Paton, 1998. Bangladesh: Flora of Chittagong hill tracts, Dr. King’s Collector, viii.1886, Herb. Hort. Bot. Calcuttensis, CAL 351774! CAL 351775! India, Andhra Pradesh: Godavari, M.S. Ramaswami, 13.viii.1914, CAL 351792! Coll.No.1682; East Godavari, Daragatta, M. Mohanan, 17.xii.1993, altitude 550m, BSID0005839! Coll.No.100749. Assam: Flora of North Cachar, Haflong, William Craib, 17.viii.1908, Herb. Hort. Bot. Calcuttensis, CAL 351776! Koliapani, N. Kalita & S. Haque, 20.v.2001, ARUN000012603! and 16.xii.2008, ARUN000012604! Karnataka: Flora of North Kanara, W.A Talbot, 1889, CAL 351800! Coll.No.1935; Coorg, Mercara, B.C Banerjee, 31.x.1976, CAL 0000008663! Coll.No.11686. Kerala: Flora of Travancore, Quilon, M. Rama Rao, 13.viii.1913, CAL 351785! Coll.No.2252; Kozhikode, Kapad Shore, T.A. Rao, 09.xi.1972, CAL 11412! Coll.No.9839. Lakshadeep: Chetlat Island, B.M. Wadhwa, 28.ii.1959, CAL 6616! CAL 6617! Coll.No.49132. Manipur: Flora of Munneypore, Irang, C.B. Clarke, 27.xi.1885, CAL 351777! Flora of Manipur, Bishenpur, A. Meebold, xi.1907, No accession number. Odisha: Ganjam, Rocky hill Gopalpur, D. Prain, 1889, CAL 351793! Ramgiri, G.V. Subba Rao 19.xii.1962, ASSAM 36069! ASSAM 36070! Tamil Nadu: Coimbatore, Bolampatti Valley, C.E.C. Fisher, 22.ix.1900, altitude 1600m, CAL 351790! Coll.No.2205; AlagarKoil reserve forest, S. R. Srinivasan, 20.x.1988, altitude 300 m, BSID0012445! Coll.No.89407. Telangana: Khammam, Perantappally Forest, Pappikonda Hills, R. Chandrasekaran, 19.ii.1994, altitude 250 m, BSID0005841! Coll.No.98988; Borapuram (Mahabubnagar), B. Sadasivaiah & S. Khadar Basha, 04.xi.2008, altitude 615 m, BSID0005843! Coll.No.32360. Tripura: Rajnagar, B.K. Huidrom, 26.viii.1995, ASSAM 57229! Assam: Jorhat, Near Hoollongapar Gibbon sanctuary, 26.6785654N 94.3555723E, altitude 93 m, 21.vii.2019, Mamita Kalita, Coll.No. 63 (JHOG02).

Taxonomic note

The variety epithet `macrophyllum᾽ is a Greek word which intent large-sized leaves of the specimen. Earlier, five varieties of ssp. gratissimum, have been recognized, one by Hooker (1885) and the rest four by Briquet (1894, 1898). Hooker (1885) reduced O. suave Willd. to a variety of O. gratissimum var. suavis, and distinct the variety from O. gratissimum in leaf pubescence. Briquet (1894) established three varieties, viz., macrophyllum, mascarenarum, hildebrandtii, and later subdentatum in 1898. However, only a single variety (macrophyllum) is acknowledged, and the others are accepted as synonyms. Morton (1962) found insufficient evidence for establishing intermediates of O. gratissimum. He considered O. suave and O. gratissimum as different species based on chromosome number, 2n = 64 and 2n = 40, 48, respectively. Similar chromosome numbers (2n = 64) were obtained by Darlington & Wylie (1955) from the Indian material of O. gratissimum. Also, differences based on leaf epidermal characteristics were analyzed by Olowokudejo & Pereira-Shateolu (1988). Khosla (1995) found O. suave contrasting from O. viride Willd. and O. gratissimum. Based on taxonomic and genetic relationships, he further concluded their origin from a common ancestor. Currently, both O. suave and O. viride exists as a synonym of O. gratissimum ssp. gratissimum. The var. macrophyllum is definite from var. gratissimum in having lax inflorescence and sparse indumentum. This incarceration is held up by referencing Indian material, where the discontinuity between the two varieties is also supported. The consulted herbarium specimens ARUN000012603, ARUN000012604, CAL 351776 pertaining to Assam and CAL 351777, ASSAM 57229 of Manipur and Tripura, respectively, are identified as Ocimum gratissimum. However, these specimens were found morphologically dissimilar from the variety described in the present study. Thus, it led to an establishment of new distribution record for the var. macrophyllum in northeastern India.

Discussion

The species O. gratissimum popularly known as scent leaf, has potential bioactive compounds such as polyphenols and flavonoids. The var. macrophyllum is undoubtedly similar to clove basil, which may serve as an alternative to drugs. The variety can also make its appearance as a new medicinal plant. O. gratissimum L. ssp. gratissimum var. macrophyllum Briq. is a new distributional record for northeastern India and Assam. The investigations of var. macrophyllum are similar to the description given by Paton (1992) while revising the tribe Ocimeae in Africa. The present study has provided comprehensive data on the odoriferous specimen’s diagnosis, distribution, elucidation, and taxonomic status.

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References

Albuquerque, U.P. & L.H.C. Andrade (1998). El género Ocimum L. (Lamiaceae) en el Nordeste del Brasil. Anales del Jardín Botánico de Madrid 56(1): 43–64. https://doi.org/10.3989/ajbm.1998.v56.i1.219

Bentham, G. (1832). Labiatarum Genera Et Species. James Ridgway and Sons, London, 1 pp.

Briquet, J. (1894). Fragmenta Monographiae Labiatarum, pp. 120. In: Boissier, A.L.H. Bulletin De L’Herbier Boissier. Genève Imprimerie Romet Boulevard De Plainpalais 2: 736 pp.

Briquet, J. (1898). Annuaire du Conservatoire et du Jardin Botaniques de Genève. Conservatoire Botanique Genève, 2: 242 pp.

Darlington, C.D. & A.P. Wylie (1955). Chromosome Atlas of Flowering Plants. George Allen and Unwin Limited, London, 328 pp.

Hooker, J.D. (1885). The Flora of British India. Reeve and Company Limited, Ashford, Kent. 4: 609 pp.

Khosla, M.K. (1995). Study of Inter-relationship, phylogeny, and evolutionary tendencies in genus Ocimum. Indian Journal of Genetics and Plant Breeding 55(1): 71–83.

Morton, J.K. (1962). Cytotaxonomic studies on the West African Labiatae. Botanical Journal of the Linnean Society 58(372): 231–283. https://doi.org/10.1111/j.1095-8339.1962.tb00896.x

Olowokudejo, J.D. & O. Pereira-Shateolu (1988). Taxonomic value of epidermal characters in the genus Ocimum (Lamiaceae). Phytomorphology 38(2–3): 147–158.

Paton, A.J. (1992). A synopsis of Ocimum L. (Labiatae) in Africa. Kew Bulletin 47(3): 403–435. https://doi.org/10.2307/4110571

Paton, A. J., 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 (2009). Lamiaceae (Labiatae), pp. 137–174. In: Beentje, H.J., S.A. Ghazanfar & R.M. Polhill (eds.). Flora of Tropical East Africa (FTEA). East African Governments by Royal Botanic Gardens, Kew, UK, 436 pp.

Pushpangadan, P. & S.N. Sobti (1982). Cytogenetical Studies in the Genus Ocimum L. Origin of O. americanum, cytotaxonomical and experimental proof. Cytologia 47(3–4): 575–583. https://doi.org/10.1508/cytologia.47.575

Roxburgh, W. & W. Carey (1832). Flora Indica, or Descriptions of Indian Plants. Serampore, Printed for W. Thacker and Company Calcutta, Parbury, Allen and Company, London. 3: 17pp. https://doi.org/10.5962/bhl.title.590

Ryding, O. (2000). Lamiaceae (Labiatae), pp. 341. In: Thulin, M. Flora Somalia. Kew Richmond, Royal Botanic Gardens, UK, 626pp.

Suddee, S., A.J. Paton & J.A.N. Parnell (2005). Taxonomic Revision of Tribe Ocimeae Dumort. (Lamiaceae) in Continental South East Asia III. Ociminae. Kew Bulletin 60(1): 3–75.

Stevens, P.F. (2001 onwards). Angiosperm Phylogeny Website, Version 14. http://www.mobot.org/MOBOT/research/APweb/ Electronic version accessed on 20 April 2023.

Vieira, R.F., R.J. Grayer, A. Paton & J.E. Simon (2001). Genetic diversity of O. gratissimum L. based on volatile oil constituents, flavonoids and RAPD markers. Biochemical Systematics and Ecology 29(3): 287–304. https://doi.org/10.1016/S0305-1978(00)00062-4