AMORPHOPHALLUS PAEONIIFOLIUS

Species

PROTOLOGUE: Amorphophallus paeoniifolius (Dennst.) Nicolson, published in Taxon 26: 338 (1977).

Amorphophallus paeoniifolius (Dennst.) Nicolson, Taxon 26: 338 (1977). Dracontium paeoniifolium Dennst., Schlüssel Hort. Malab.: 13, 38 (1818), as 'paeoniaefolium'. Lectotype: Rheede's illustration of Mulenschena in Hortus Malabaricus 11: t. 19 (1692), designated by Nicolson, Taxon 26: 338 (1977).

SYNONYMS:

HOMOTYPIC SYNONYMS: Amorphophallus giganteus Blume in Rumphia 1: 144 (1837), nom. illeg. Arum rumphii Gaudich. in Voy. Uranie: 43 (1826), nom. illeg. Candarum hookeri Schott in H.W.Schott & S.L.Endlicher, Melet. Bot.: 17 (1832), nom. illeg. Candarum roxburghii Schott in H.W.Schott & S.L.Endlicher, Melet. Bot.: 17 (1832), nom. illeg. Candarum rumphii Schott in H.W.Schott & S.L.Endlicher, Melet. Bot.: 17 (1832), nom. illeg. Conophallus giganteus Schott ex Miq. in Fl. Ned. Ind. 3: 198 (1856), nom. illeg. Dracontium paeoniifolium Dennst. in Schlüssel Hortus Malab.: 38 (1818) Kunda verrucosa Raf. in Fl. Tellur. 2: 82 (1837), nom. illeg.

HETEROTYPIC SYNONYMS: Amorphophallus campanulatus Decne. in Nouv. Ann. Mus. Hist. Nat. 3: 366 (1834) Amorphophallus campanulatus var. blumei Prain in Bengal Pl. 2: 1109 (1903) Amorphophallus campanulatus f. darnleyensis F.M.Bailey in Queensland Agric. J., n.s., 1: 124 (1914) Amorphophallus chatty Andrews in Ill. Hort. 19: 361 (1872) Amorphophallus decurrens (Blanco) Kunth in Enum. Pl. 3: 581 (1841) Amorphophallus dixenii K.Larsen & S.S.Larsen in Reinwardtia 9: 141 (1974) Amorphophallus dubius Blume in Rumphia 1: 142 (1837) Amorphophallus gigantiflorus Hayata in Icon. Pl. Formosan. 6: 101 (1916) Amorphophallus malaccensis Ridl. in J. Straits Branch Roy. Asiat. Soc. 41: 46 (1904) Amorphophallus microappendiculatus Engl. in Notizbl. Bot. Gart. Berlin-Dahlem 8: 458 (1923) Amorphophallus paeoniifolius var. campanulatus (Roxb.) Sivad. in Taxon 32: 130 (1983) Amorphophallus rex Prain in J. Asiat. Soc. Bengal, Pt. 2, Nat. Hist. 62: 79 (1893) Amorphophallus sativus Blume in Rumphia 1: 145 (1837) Amorphophallus virosus N.E.Br. in Gard. Chron., n.s., 23: 759 (1885) Arum campanulatum Roxb. in Pl. Coromandel 3: 68 (1820) Arum decurrens Blanco in Fl. Filip.: 656 (1837) Arum phalliferum Oken in Allg. Naturgesch. 3(1): 595 (1841) Arum rumphii Oken in Allg. Naturgesch. 3(1): 595 (1841) Conophallus sativus (Blume) Schott in Prodr. Syst. Aroid.: 35 (1860) Dracontium polyphyllum G.Forst. in Pl. Esc.: 61 (1786), sensu auct. Dracontium polyphyllum Dennst. in Schlüssel Hortus Malab.: 38 (1818), nom. illeg. Dunalia artensis Montrouz. in Actes Soc. Linn. Bordeaux 26: 576 (1866) Hydrosme gigantiflora (Hayata) S.S.Ying in Mem. Coll. Agric. Natl. Taiwan Univ. 31(1): 31 (1991) Plesmonium nobile Schott in Ann. Mus. Bot. Lugduno-Batavi 1: 279 (1864) Pythion campanulatum (Roxb.) Mart. in Flora 14: 459 (1831)

DISTRIBUTION: Trop. & Subtrop. Asia to N. Australia: Andaman Islands, Assam, Bangladesh, Borneo, Cambodia, China South-Central, China Southeast, East Himalaya, Hainan, India, Java, Laos, Lesser Sunda Islands, Peninsular Malaysia, Maluku, Myanmar, New Guinea, Northern Territory, Philippines, Sri Lanka, Sulawesi, Sumatra, Taiwan, Thailand, Vietnam.

DISTRIBUTION NOTE: Introduced into: Comoros, Cook Is., Fiji, Madagascar, Marquesas, New Caledonia, Niue, Samoa, Seychelles, Society Is., Trinidad-Tobago, Vanuatu iNaturalist: Andhra Pradesh, Batangas, Cavite, Central Sulawesi, Changhua, Chhattisgarh, Chiang Mai, Chiang Rai, Chiayi City, Chon Buri, Goa State, Hải Phòng, Karnataka, Kerala, Khon Kaen, Krabi Province, Mae Hong Son, Maharashtra, Nakhon Ratchasima, Nantou, North Sulawesi, Odisha, Papua New Guinea, Phetchaburi, Pingtung, Rayong, Saraburi, Satun Province, South Sulawesi, Surat Thani, Tainan, Uttar Pradesh, West Bengal, Yunlin, Yunnan.

SPECIES DESCRIPTION:

Tuber depressed-globose. Petiole up to 1.2 m long, smooth or muricate, mottled.⁸

INFLORESCENCE:

Inflorescence short-peduncled, elongating after anthesis. Spathe broadly campanulate, c. 25 x 28 cm, convolute below and spreading above. Spadix sessile, differentiated into a basal female portion, a subturbinate or subcylindric male portion, and an apical naked sterile appendix, sessile, subglobose or elongate-conoid, wrinkled at maturity and spongy within. Ovary light purplish or pale yellowish, 2-3-locular, each locule with a single anatropous ovule; style elongate; stigma yellowish, reniform or 2-3-lobed. Male flowers creamy-yellow.⁸

PROPAGATION:

This has proven to be a most difficult species to propagate from leaf blade cuttings. Of Juniper Level Botanic Garden's 12 different trials, only one was successful. One batch of early August cuttings resulted in 27.1% rooting. Even with proper timing, this was among the most difficult species to root.

ETYMOLOGY:

From Latin, “with leaves like a peony” - paeonia plus folium. Dennstedt printed it as paeoniaefolium in 1818, and the spelling was later corrected to paeoniifolium under the rules of botanical nomenclature. He applied the name not to a plant in his hand but to a picture: Rheede's engraving of Mulenschena, plate 19 of the eleventh volume of the Hortus Indicus Malabaricus.⁹,¹⁰

NOTES:

1. The name has no conventional protologue. Dennstedt published Dracontium paeoniaefolium in 1818 through a single cross-reference in a key to Rheede's Hortus Indicus Malabaricus - the entry reads only "Mulen-Schena - Dracontium paeoniaefolium. XI. 19." The descriptive and illustrative basis of the name is therefore Rheede's own account and plate of 1692.⁹,¹⁰

2. Nicolson made the modern combination in 1977 and at the same time designated Rheede's plate 19 as the lectotype, so the type of Amorphophallus paeoniifolius is a seventeenth-century engraving rather than a herbarium specimen.²

3. ⚠ Two plates in that volume are easily confused. Plate 18 is Schena, generally taken to be the cultivated form with a smooth petiole; plate 19 is Mulenschena, the wild form with a strongly muricate petiole. The name paeoniifolius is anchored to plate 19. Because the two are so alike, the name Amorphophallus campanulatus was long used for both.⁸

4. Recognising that an earlier legitimate epithet existed for Mulenschena is what rendered Arum campanulatum Roxb. illegitimate: Roxburgh had cited Rheede's plate 19 in his own synonymy, which brought the earlier name's type into his.⁸

5. The wild and cultivated elements are treated as two varieties. In var. paeoniifolius the petiole is usually purplish brown with light pinkish blotches and strongly muricate in its basal half, the leaflet bases run strongly down the primary rachises, the appendix is elongate-conoid and taller than broad, the style is about twice the height of the ovary and the stigma is usually 2-lobed. In var. campanulatus the petiole is greenish with white blotches and smooth or nearly so, the leaflet bases do not reach the junction of the primary rachises, the appendix is subglobose and broader than tall, the style is three to four times the ovary height and the stigma is usually 3-lobed.⁸

6. It is recorded from India, Sri Lanka and the Pacific islands, and in India from almost every state.⁸

7. Ron McHatton, who grew Amorphophallus paeoniifolius in central Florida, called the species very variable in cultivation: some plants stay fairly short, while others, especially a group called “Borneo Giant,” can reach 8 to 9 feet tall. Leaflet number and petiole roughness also vary a great deal. In his plants, a group raised from seed in Florida had virtually smooth petioles, plants from China were somewhat rougher, and another group had extremely rough petioles.¹²

8. Dr. Raj Shekhar Misra of India's Central Tuber Crops Research Institute wrote in September 2009 that he grows a giant form of Amorphophallus paeoniifolius whose edible corms weigh 15 to 20 kg.¹³ In the same discussion, a grower named Derek wrote that he finds corms of the size under discussion in United Kingdom greengrocers in summer and was told the general name is suran, that he did not consider a corm 24 inches across particularly unusual, and that his own Amorphophallus paeoniifolius corms reach at least 18 inches across.¹⁴

9. Michael Pascall, growing Amorphophallus paeoniifolius outdoors in ideal wet tropical conditions with plenty of mulch and fowl manure, reported that a tuber of more than 30 cm flowered about two years after starting as a 2 cm tuber, and that a few slightly smaller tubers he had dug up and left lying around flowered as well. This is one grower's report, with no tuber weight and no planting date.¹⁵

10. Scott Hyndman of Vero Beach, Florida (USDA hardiness zone 10a), over-fertilized his large Amorphophallus paeoniifolius in a 150-gallon pot, especially while the new tuber was growing. The leaf edges turned yellow, then brown and crumbly, which he attributed to high soluble salts, and the foliage looked as though the plant was about to die. The plant nevertheless produced a healthy tuber of about 70 pounds (about 32 kg) that, as of May 5th, 2001, was about to bloom.¹⁶

STORY:

STORY TITLE: The plant whose type is a painting from 1692

Almost every plant name in this genus rests on a dried specimen in a herbarium cabinet. The elephant-foot yam rests on an engraving made in Cochin in the seventeenth century.

Between 1678 and 1693, Hendrik van Rheede, the Dutch governor of Malabar, produced the Hortus Indicus Malabaricus: twelve folio volumes describing the plants of the Kerala coast, compiled with Malayali physicians and Ezhava practitioners whose knowledge the work openly credits. Each plant was engraved at life scale and captioned in four scripts - Latin, Malayalam, Arabic and Devanagari. In volume XI, published in 1692, two plates sit side by side. Plate 18 shows Schena, the smooth-stalked yam grown in gardens. Plate 19 shows Mulenschena, the wild one, its stalk rough and studded - mulen for the prickles.

For more than a century nobody attached a formal name to either. Then in 1818 August Wilhelm Dennstedt published a slim key to Rheede's work, a book whose whole purpose was to give the vernacular names their Linnaean equivalents. Against Mulen-Schena he wrote seven words and a number: Dracontium paeoniaefolium. XI. 19. No description, no specimen, no herbarium sheet. The name was published, validly, by pointing at a picture.

That casual line turned out to have priority over everything that followed. Roxburgh's Arum campanulatum of 1819 cited Rheede's plate 19 in its own synonymy and so became illegitimate; the name Amorphophallus campanulatus, in general use for a century and a half, went the same way. In 1977 Dan Nicolson worked the chain back to its source, made the combination Amorphophallus paeoniifolius, and formally designated Rheede's plate 19 as the lectotype - fixing the identity of the most widely eaten aroid on earth to a drawing made 285 years earlier.

It is grown from Madagascar to Polynesia and across almost every state of India, and taxonomists still separate the wild plate-19 plant from the cultivated plate-18 one as two varieties. The distinction Rheede's engravers drew in 1692 - rough stalk against smooth - is the same one the key uses today.

CULTIVARS:

Amorphophallus paeoniifolius ‘Gajendra’

Amorphophallus paeoniifolius ‘Sree Athira’

Amorphophallus paeoniifolius ‘Thailand Giant’

REFERENCES:

1. Plants of the World Online, Royal Botanic Gardens, Kew — Amorphophallus paeoniifolius (Dennst.) Nicolson

2. Taxon 26: 338 (1977) — protologue.

3. Alan Galloway — Amorphophallus paeoniifolius, alangallowaybotanicals.com.

4. Wight, R. 1846. Icones Plantarum Indiae Orientalis 3: t. 782, Arum campanulatum

5. Hetterscheid, W.L.A. & Ittenbach, S. 1996. Everything you always wanted to know about Amorphophallus, but were afraid to stick your nose into!!!!! Aroideana 19: 7–131

6. Propagation of Amorphophallus by Leaf Petiole Cuttings — Juniper Level Botanic Garden

7. iNaturalist: Amorphophallus paeoniifolius