14 AROIDEANA Vol. 13, No. 1-4

Germination of1Yphonodorum lindleyanum at Brisbane, Australia

Dorothy E. Shaw Pathology Branch Department of Primary Industries Meiers Road Indooroopilly, Q 4068 Australia

The giant Madagascar swamp aroid, shaped leaves. Later lanceolate leaf Typhonodorum lindleyanum Schott, has blades gradually form until finally, like­ been successfully grown in an artificial wise gradually, the sagittate or arrow­ lake at the Mt. Coot-tha Botanic Gardens head-shaped adult leaves are produced. near Brisbane. have flowered and Engler included drawings of two germi­ produced fruit and new plants have been nating seedlings, one with four cata­ established from the germinated seed­ phylls (early leaf forms) and one with lings. As early literature may not be five cataphylls and one leaf with blade. readily available to some readers, a brief Ridley (930) stated that the one­ account of germination is given below. seeded and viviparous fruits of T. lindley­ anum were eaten by the locals. He also Some Early literature stated that after floating, the young plant was eventually stranded in the mud. This large aquatic aroid, up to 3-4 m Tillich (985) included a drawing of one high, with emergent stems and leaves, germinated seed with three young and has been recorded in Madagascar and on the neighboring islands of Mauritius, the three older cataphylls, and some young Comoro Islands, and Zanzibar in East roots in his short account in German. (Engler, 1915). A detailed descrip­ In his key of the aroids, Nicolson tion of the plants and floral parts (in Latin (982) gave the ovules as 1 (rarely 2) with German comments) and with illus­ orthotropous (the orientation of the trations was given by Engler. He de­ ovule in the ovary in an upright position scribed the berry or fruit as large (about from the placenta where it is attached to 2.5 em long), one-seeded and viviparous, the maternal tissue), the seeds as without that is, with the plumule or shoot devel­ endosperm and a very large embryo. oped within the seed while still attached French (986) described ovules and their to the parent plant, and with a large well-developed vascular system. 'haustorial' process at the base. After flowering, the upright peduncle of the ~sent~tions inflorescence gradually turns down­ wards, exhibiting positive geotropism, so As I needed to obtain seedlings of T. that it becomes goose-necked. The fruit lindleyanum for a pathology study, the (already with curved shoot inside) falls Curator of the Botanic Gardens gave into the water as the tip of the spathal permission for the collection of the fruit chamber opens and releases them. The and also provided a small skiff and a staff fruit remain floating on their sides for member as rower to enable me to reach some time. the Typhonodorum growing in the lake After the fruit has anchored into a in May 1988. The group consisted of substrate (swamp bank or whatever) the seven plants with 11 pseudostems and seedling produces some narrow awl- some infructescences (Fig. 1). Fig. l. Typhonodorum lindleyanum growing in a lake at Mt. Coot-tha Botanic Gardens in Brisbane. 16 AROIDEANA Vol. 13, No. 1-4

2 eM 2 3 -

5 -2 eM

-2 eM 6 Fig. 2. T lindleyanum infructescence. Fig. 3. T lindleyanum infructescence, cut open to show the position of the viviparous fruit which would later drop downwards into the water. Fig. 4. Yell owish fruit of T lindleyanum with coats and dark brown fruit without coats fl oating on their sides in a deep beaker of water. Fig. 5. Four fruit of T lindleyanum. Fig. 6. Four fru it showing the emerging, previously curved plumules. DOROTHY E. SHAW, 1990 17

Fig. 7. Four seedlings of T lindleyanum 39 days after sowing. Fig. 8. Roots of one seedling 39 days after sowing. Fig. 9. Two lots of seedlings of T lindleyanum, one lot grown in damp soil and the other in water-logged soil , 9.5 weeks after sowing. Fig. 10. Roots of the seedlings shown in Fig. 9. 18 AROIDEANA Vol. 13, No. 1-4

The oldest infructescences were al­ of the young seedlings again lacked root ready pointing downwards on curved hairs. Microscopic examination of the peduncles. One detached infructescence roots of one of these plants after growing is shown in Fig. 2 and one cut to reveal in an outside pond for 14 months also the enclosed whitish fruit in Fig. 3. showed hairlessness. Roots from the The fruit of some of the infructes­ plants shown in Fig. 11 were also exam­ cences had already fallen into the water ined microscopically 30 months after and were floating around the plants and sowing when they were 2.5 m high and between the water lily leaves. Some of were also found to be without root hairs. the fruit with the outer coat still intact (now pale yellow) and some with the Comments coat rotted off are both shown floating on their sides in a 19 cm deep beaker of The roots of the seedlings and of water (Fig. 4). Four of the latter fruit are plants up to 30 months old lacked root shown in Fig. 5 and four others with their hairs. Although no root hairs are shown plumules emerging from their former in the drawings of Engler (1915) or Tillich (1985), this fact is not mentioned curved position in Fig. 6. Eighteen of the fruit were sown on by either author, even though Tillich, for example, mentioned the hairlessness of their sides in a shallow dish of potting roots of other plants. Another aquatic mix (hereafter called 'soil') partially cov­ aroid, Pistia stratiotes 1., also lacks root ered with water on 17 May 1988. The hairs (Schwarz 1883; Tillich 1985; and plumules were negatively geotropic, ris­ Shaw, personal observation). Mature ing into the air. Four of the seedlings are plants of T. lindleyanum in their natural shown in Fig. 7, taken 39 days after habitat may also lack root hairs, and if sowing in the tray. A close-up of the roots this has not been investigated already, of one of them is shown in Fig. 8. The needs to be determined. main roots had a reddish pigment near T. lindleyanum grows in great profu­ the base of the plant shading into white sion in swamps and marshes near Tamat­ towards the tip. The lateral roots issued ave (18· 10' S latitude) and in the lower at right angles to the main roots and were reaches of rivers on the east coast of white and translucent (Fig. 8). When Madagascar facing the Indian Ocean, as examined microscopically, neither the shown in illustrations such as those of main roots nor the laterals had root hairs. Rue, Bouliere & Harroy (1957) and Graf The seedlings were grown on in food (1981, 1982), although it is said to extend jars, nine of them in soil kept damp and to 900 m altitude (Croat (1988)1990). It nine maintained with water above the also grows on the Comoro Islands (about soil surface. Both lots were about 55 cm 12· S) and Zanzibar (6· 19' S) which are above soil level 9.5 weeks later (Fig. 9). much further north. It has been culti­ The roots, washed free from soil, are vated outdoors in the Botanic Gardens at shown in Fig. 10, and those from both Rio de Janeiro (22· 53' S), as illustrated by damp and waterlogged soil were still Graf (1982) in color. The plant has also without root hairs. been growing outside at Brisbane (2T Some of the plants were grown on by 30' S) which is slightly colder than even a grower with suitable facilities and were Rio de Janeiro, as well as in the warmer nearly 2 m above soil level in July 1989, geodesic dome at the Mt. Coot-tha Bo­ that is, 14 months after sowing (Fig. 11). tanic Gardens (Shaw 1987). A further collection of infructescences Seedlings at Brisbane, however, was made by a Gardens staff member in grown in an outside pond were smaller September 1989 and the germination of (about 1 m high) at 14 months than those this material followed the same pattern grown the previous year in the glass­ as previously. The main and lateral roots house (as shown in Fig. 11). Those Fig. 11. Plants of T. lindleyanum (originally shown in Fig. 9) 14 months after growth in a glasshouse. 20 AROIDEANA Vol. 13, No. 1-4 grown in the glasshouse had reached Laboratory, U. K., for botanical advice nearly 2 m high in the same time. and the Director, Plant Patholog; Bown (988) described T. lindley­ Branch, for facilities during this study. D ~mum and mentioned that in many ways it resembles the American ' the literature Cited latter, however, is only knee-high an'd its staminodes (sterile stamens) are joined Bown, D. 1988. Aroids. Plants of the Arum Family. London: Century. 256 together, whereas they are free in T. pp. (p. 97). lindleyanum. Also, the three dimensional Croat, T. B. (988) 1990. Ecology and Life organization of vascular bundles in the Forms of . Aroideana 11:4- ovules in Typhonodorum and Peltandra are different: in Typhonodorum about six 55. Engler, A. 1915. Araceae. Philodendroi­ bundles are symmetrically arranged deae-Anubiadeae, Aglaonemateae, around the circumference of the chalaza Dieffenbachieae, Zantedeschieae (the basal region of the ovule), whereas Typhonodoreae, Peltandreae. Heft the bundles occur in the dorsal region of 64:1- 80. (pp. 69-71) Peltandra (French 1986). Bown (988) French,]. C. 1986. Ovular vasculature in discussed Grayum's (984) suggestion Araceae. Bot. Gaz. 147:478-495. that Typhonodorum and Peltandra may have had the same ancestor in Africa Graf, A. B. 1981. Tropica 2nd Edition. East Rutherford, USA: Roehrs Co. before the continents drifted apart after 1136 pp. (p. 127) populations of the plants had spread into 1982. Exotica Interna­ what is now Asia and Europe and then tional Series 4. Library Edition Vol. 1. across to North America. In this scenario those that remained on the mainland of 2560 pp. (pp. 295, 303). Africa later became extinct during the Grayum, M. H. 1984. Palynology and Phylogeny of the Araceae. University ages of drought, leaving survivors in of Massachusetts Ph.D. Thesis. 852 North America and on islands east of pp. Ann Arbor, Michigan: University Africa. These separate populations con­ Microfilm International xxiii. (Not tinued to evolve: those in North America seen, cited by Bown 1988). becoming Peltandra and the Madagas­ Nicolson, D. H. 1982. Translation of can dynasty forming the monotypic Ty­ Engler's Classification of Araceae phonodorum. with updating. Aroideana 5:67-88. Not many private gardens have grow­ Ridley, H .. N. 1930. The Dispersal of ing areas large enough to contain a pond Plants Throughout the World. or lake suitable for the growth of this Ashford, U. K.: L. Reeve & Co. Ltd. giant aquatic aroid. In large gardens, however, the plants are spectacular items 712 pp. (pp. 235-236). Rue, A. de la, F. Bourliere &]. P. Harroy. in the landscape. It is also, of course, of great interest from a botanical and evolu­ 1957. The Tropics. London: George tionary point of view. G. Harrap & Co. Ltd. 208 pp. (p. 79). Schwarz, F. 1883. Die Wurzelhaare der Acknowledgements Pflanzen. Unters. Bot. Inst. Tubinger (Pfeffer, W.) 1:135-188 (p. 167). I wish to thank Mr. R. D. McKinnon Shaw, D. E. 1987. The Two Botanic Curator of the Mt. Coot-tha Botani~ Gardens in Brisbane, Australia, and Gardens for permission to sample the Their Aroids. Aroideana 10:4-15 plants; Messrs. ]. Gilby and A. D. Rains­ (Fig. 7). forth, Gardens staff members, for assis­ Tillich, H.-]. 1985. Keimlingsbau und tance in collecting; Mr. E. Frazer for help Verwandtschaftliche Beziechungen in root sampling; Ms. M. Gregory, Jodrell der Araceae. Gleditschia 13:63-73.