Pandanus (PROSEA Fibres)

Plant Resources of South-East Asia
Introduction

List of species

Pandanus Parkinson

Protologue: J. voy. South Seas: 46 (1773).

Family: Pandanaceae

Chromosome number: x= 30;P. furcatus,P. odoratissimus: 2n= 60

Major species and synonyms

Pandanus atrocarpus Griffith, Not. pl. asiat. 3: 160 (1851), synonym: P. caricosus auct. non Sprengel.

Pandanus furcatus Roxb., Hort. bengal.: 71 (1814), synonyms: Rykia furcata (Roxb.) De Vriese (1854), Pandanus houlletii Carr. (1868). Note: some authors consider P. houlletii to be a separate species.

Pandanus kaida Kurz, J. As. soc. beng. 38(2): 148 (1869), synonyms: P. siamensis Williams (1904), P. forceps Martelli (1905).

Pandanus odoratissimus L.f., Suppl. pl.: 64 (1782, excl. syn. Keura Forsskal), synonyms: P. fascicularis Lamk (1783), P. sabotan Blanco (1837), P. tectorius auct. non Parkinson.

Pandanus tectorius Parkinson, J. voy. South Seas: 46 (1773) [ex Z. (J.P. du Roi), Der Naturforscher 4: 250 (1774)], synonyms: P. bagea Miquel (1855), P. robinsonii Merrill (1917), P. veitchii hort.

Vernacular names

General: pandan, pandanus, screwpine (En).

P. atrocarpus : Indonesia: mengkuang, bengkuang (Malay)
Malaysia: mengkuang, bengkuang, pandan duri.

P. furcatus : Indonesia: bengkuang (Malay), pandan kowang (Javanese), harashas (Sundanese)
Malaysia: mengkuang hutan, pandan hutan
Thailand: kiang paa, kiang luang (northern), keng-luang.

P. kaida : Malaysia: mengkuang
Thailand: toei (general), toei saan suea (Bangkok)
Thailand: toei (general), toei saan suea (Bangkok)
Vietnam: dửa (general), giửa dại (Ha Son Binh).

P. odoratissimus : Indonesia: pandan laut (Malay, Sundanese), pandan pasir (Javanese)
Philippines: sabotan, sibutan (Tagalog), parauan (Gaddang)
Cambodia: rumche:k (general)
Laos: (do:k) ke:d (Louang Prabang)
Thailand: kaaraket, toei thale, lam chiak (central)
Vietnam: giửa (dửa) dại (Ha Nam Ninh).

P. tectorius : Indonesia: pandan pudak (general)
Thailand: kaaraket, kaaraket daang, lam chiak nuu (Bangkok).

Origin and geographic distribution

Pandanus contains about 700 species and is found from West Africa eastward through Madagascar, the Indian Ocean Islands, South and South-East Asia, southern China, Taiwan, Japan and Australia into the Pacific. Here it reaches its northern outpost in Hawaii, and its eastern and southern outposts in Pitcairn and Henderson Islands. Many endemic species exist. Pandanus is cultivated in other parts of the tropics and indoors in more temperate regions.

P. atrocarpus is common in Peninsular Malaysia, Singapore, Sumatra and Bangka. P. furcatus is found in India, Sri Lanka, Nepal, Burma (Myanmar), and in Peninsular Malaysia and Indonesia (Java, Sumatra) if P. houlletii is considered as a synonym. P. kaida probably originates from South-East Asia, or perhaps from India or Sri Lanka. It is not known for certain as a wild plant, but is widely cultivated from India and Sri Lanka to the eastern perimeter of continental Asia (Malaysia to China). P. kaida is often confused with P. odoratissimus or P. tectorius , but it is generally not found along beaches or even outside cultivation. P. odoratissimus is widely distributed on the Indo-Malaysian coasts from India and Sri Lanka throughout South-East Asia to Taiwan, the Ryukyu Islands and Micronesia. It is the predominant wild Pandanus of the sandy coasts in Malesia, but it is also often cultivated in the interior. P. tectorius is widespread in the Pacific Islands, particularly Polynesia and Melanesia, extending north to the Hawaiian Islands, and west to Australia, New Guinea, the Moluccas and the Philippines. In this vast area and elsewhere in the tropics, P. tectorius is also often cultivated. P. tectorius is closely related to P. odoratissimus and the two species may be regarded as Melanesian-Pacific-Australasian and West Malesian vicariants, respectively.

Uses

Pandanus leaves, usually reduced to strips, are used for weaving a range of articles, from small handbags and containers to large floor mats or light interior wall panels. All long-leaved Pandanus spp. are potential sources of weaving material. The leaves also serve for thatching. The leaves, stems or prop roots may be retted to obtain fibres which are used for twine and ropes. Epidermal strips sometimes serve as substitutes for cigarette paper. Unfortunately it has been customary to ascribe the main littoral and cultivated Pandanus spp. to a single species, either P. odoratissimus or P. tectorius and it is often difficult to separate the recorded uses of these two species in literature sources. The leaves of P. odoratissimus and P. tectorius are made into hats, mats, sacks, cordage, baskets, umbrellas and other articles. In the Philippines "sabotan fibre" from the leaves of P. odoratissimus is used for the manufacture of, for example, the strong and durable "sabotan hats", high quality sleeping mats, hammocks, cushions, bags, slippers and picture frames. The leaves also serve for thatching. On Guam they have been used to make sails. Beaten prop roots are used as brushes for painting and whitewashing, and the roots serve for binding. The leaves are said to be good paper-making material. The large, very tough leaves of P. atrocarpus are used extensively in Peninsular Malaysia and Indonesia (Sumatra, Bangka) for the production of durable mats, including waterproof mats ("kajangs") to cover carts and boats. Cut into finer ribbons, they are made into hats. On Bangka the leaves have been used to make sails. P. atrocarpus also serves for thatching. P. furcatus is used for matting, for instance in Indonesia, Malaysia and Burma (Myanmar). Woven, untrimmed leaves have been made into covers for quivers in Malaysia. The leaves of P. kaida are woven into products such as mats, hats, baskets and sacks. In certain regions it is also used for the construction of houses.

Pandanus has a range of other uses. In India (mainly Orissa) and Sri Lanka the flavourings and perfumes "kewda (keora) attar", "kewda water" and "kewda oil" ("rooh kewda") are prepared from the fragrant male inflorescences of P. odoratissimus . The most important use of kewda attar is in tobacco preparations, but it also serves to flavour betel, and to scent clothes, bouquets, lotions, cosmetics, soaps, hair oils and incense sticks. Kewda attar and kewda water are both used for flavouring food, sweets, syrups and soft drinks. Kewda oil is not produced in large quantities. In Indonesia the male inflorescences of P. odoratissimus are used to scent clothes, in the preparation of fragrant oils and in ceremonies. P. tectorius var. laevis Warb. is planted in Indonesia for its fragrant inflorescences, but the odour is less long-lasting than that of P. odoratissimus . In the Andaman and Nicobar Islands the leaves of P. odoratissimus are used as cigars and the inflorescences as a substitute for tobacco. P. odoratissimus and P. tectorius have edible seeds and the pulp is also consumed after the calcium oxalate has been removed by cooking. The soft and sweet edible fruits of P. furcatus taste like overripe pineapple. The young top leaves of P. furcatus are believed to be an antidote for poisoning and are used, after roasting over a fire, against cough, whereas the leaf sap is taken against diarrhoea and dysentery. In Papua New Guinea (New Ireland) the bark of P. tectorius is scraped into a wild ginger leaf, water is added, and the solution is squeezed into a cup and drunk to sedate mental patients. In Vietnam and Cambodia the roots of P. odoratissimus are considered diuretic. P. odoratissimus is used in living fences, coastal windbreaks and is planted for soil stabilization. The wood of P. furcatus is used in Burma (Myanmar) to make floats for fishing nets. Several Pandanus spp., especially cultivated forms of P. tectorius , are grown worldwide as ornamentals for their attractive yellow and green striped leaves, indoors in temperate regions and outdoors in the tropics.

Production and international trade

In South-East Asia Pandanus spp. are usually household or village plants and not produced commercially, though products such as bags, hats and mats may enter the local economy, especially in the trade of tourist items. Woven products made of P. odoratissimus in the Philippines, however, cater to the export market. In the first half of the 20th Century large quantities of pandan hats (more than 11 million in 1925) were exported from Java. Because use is mainly local, it is hard to estimate present production.

On a monetary basis, the most important Pandanus products are kewda attar and kewda water. The demand has increased strongly since the early 1980s, due to the popularity of scented tobacco products. It is estimated that about 35 million inflorescences (about 3500 t), obtained from about 5000 ha of wild P. odoratissimus in Orissa (India), are processed annually to produce kewda attar and kewda water. Kewda oil is not produced on a commercial scale. The male inflorescences of P. odoratissimus are sold in markets in Java and Bali for high prices.

Properties

The suitability of the Pandanus leaf for weaving is due to its anatomy: the veins run parallel along the length of the leaves, whereas the transverse, connecting veins are relatively weak. The strips get their strength mainly from the upper epidermis and the hypoderm below it. Material from P. atrocarpus is flexible and strong and can be distinguished from that of other Pandanus spp. by its light yellow colour. For the production of mats from P. atrocarpus , longer, older, but still green leaves are preferred, because the younger leaves are less supple. Material from P. furcatus is greenish and less supple but more durable than that of P. atrocarpus . In South-East Asia, particularly in Peninsular Malaysia, and probably also elsewhere in South-East Asia and in India and Sri Lanka, P. kaida is the preferred Pandanus species, because of its excellent fibre quality and utility. The leaves of P. odoratissimus are quite thick and stiff.

The characteristic aroma of kewda oil is due to 2-phenylethyl methyl ether, which is the major constituent (66-85%). Another major constituent is terpinen-4-ol (9-21%). The oil is considered to have stimulant and antispasmodic properties. Root extracts of P. odoratissimus have shown anti-oxidative activity. Pericarp flesh of P. tectorius contains per 100 g edible portion: water 80 g, protein 0.4 g, fat 0.3 g, carbohydrates 19 g, fibre 0.3 g.

Adulterations and substitutes

Cyperaceae such as Scirpodendron ghaeri (Gaertn.) Merr. are used as lower-quality substitutes for Pandanus .

Description

Dioecious, evergreen, often palm-like trees or shrubs with an erect to decumbent stem, usually with rigid prop roots descending from leaf axils (or scars when leaves have fallen). Stem often branched in a trichotomous or dichotomous pattern, often knobbly or prickly, with manifest leaf scars; bark thin, often green just below the epidermis. Leaves arranged in 3 spiral rows, usually amplexicaul, linear and undivided, usually M-shaped in cross-section, usually with prickles along the margins and the underside of the midrib, in some species leaf apex on the upper surface on each side of the midrib with a sharp fold which can be prickly (prickles present or absent on strict species basis), longitudinal parallel veins numerous, leaves often somewhat pale, sometimes very glaucous beneath, sometimes variegated with achlorophyllous bands (mutant forms often perpetuated as horticultural forms), some mutant forms with unarmed leaves. Male inflorescence bracteate, usually spicate, number of spikes usually more numerous than in female inflorescences and arranged in racemes, bracts mostly white to cream or yellow, sometimes orange to purplish; spikes consisting of perianthless, strictly unisexual flowers, each flower a cluster of stamens (staminal phalange), pollen mostly white to yellowish, often scented. Female inflorescence either a globose to cylindrical head (cephalium), or a spike of such heads, upper bracts early caducous; each head consisting of either a mass of unilocular and uniovulate carpels ripening as drupes or a mass of 2- to many-celled carpels (carpellate phalange) (the stone of each ripened carpel containing 2 to many seed chambers); style absent; stigmas always distinct on the apex of each carpel. Fruit a monodrupe or a syncarpous polydrupe resembling a pineapple, ripening to yellow, orange, red, or occasionally purplish-red, the exocarp of each carpel firm to fleshy, upper mesocarp often cavernose and containing a viscid fluid or gel, lower mesocarp always fibrous and fleshy, endocarp bony; in polydrupes the carpels (and endocarps) are fused from base to almost the apex or to about middle level of the upper mesocarp. Seed fusiform or obovoid, with thin and membranous seedcoat, containing endosperm, always retained within a thin to massive thick bony endocarp; germination within the fruit.

P. atrocarpus . A massive, branched tree, stem 10-20 m × 15 cm, thorny. Leaves up to 6 m × 10-15 cm, keel and margin thorny. Male inflorescence 60 cm or longer; bracts white, lowest about 30 cm long; spikes 10-15 cm long, stamens free, filaments conical, very short, anthers much longer. Female inflorescence 90-120 cm long with woody, 3-angled peduncle 2.5 cm in diameter; heads 3-4, ovoid, 15 cm × 6 cm. Syncarp with drupes 2.5 cm long, free part conical angular, dark brown, stigma short conical-spiny, 3 mm long; mesocarp 3 mm wide, endocarp 1 cm long.

P. furcatus . A very variable, usually unbranched tree, 4-12 m tall, trunk 15-17 cm in diameter with persistent leaf bases, usually with prop roots. Leaves 2-6 m × 4-14 cm, at base dark purplish-brown, margins and underside of midrib armed with sharp prickles; longitudinal veins conspicuous, particularly at underside. Male inflorescence pendulous, 50-120 cm long, spikes 15-20 cm long. Female inflorescence pendulous on an up to 80 cm long, bracteate peduncle; head solitary, cylindrical-trigonous, 23 cm × 12 cm; styles simple or forked (lower ones), 5-6 mm long. Syncarp 20-60 cm × 8-15 cm, yellow, fragrant, fleshy, with 29 drupes in a longitudinal row and 39 drupes around the circumference; carpels 2.5-5 cm long, 5-7-angular.

P. kaida . A tree with an erect trunk 2-4 m tall, branched above with few short basal prop roots, but in cultivation usually shrub-like and kept short. Leaves 2-4 m × 6-9 cm, margins and underside midrib stoutly armed, apex long flagelliform, coriaceous, stiff, parallel veins 120-130. Male inflorescence a large raceme of spikes; each spike 8-11 cm × 3 cm, subtended by a white bract; spike composed of numerous, densely crowded, staminal phalanges 7-8 mm long, each one bearing an umbel of 12-25 white stamens. Female inflorescence with peduncle 40-50 cm long, bearing 1-3(-7) spicately arranged cephalia each one subtended by a bract; cephalia ellipsoid, up to 23 cm × 15 cm, composed of numerous, 1-4-celled carpellate phalanges; phalange 5-7-angled pyramidal, 45-50 mm × 10-20 mm; stigma 1-2 mm tall. Syncarp orange-red, individual carpels barely distinguishable; upper mesocarp 10-15 mm long, cavernose (as many chambers as carpels), lower mesocarp fibrous-fleshy, endocarp 12-15 mm long, bony, wall 1-2 mm thick, red-brown. Seed 8-10 mm long.

P. odoratissimus . A coarsely branched tree, 12-14 m tall with open crown; trunk erect or more or less decumbent, up to 20 cm in diameter, grey, near the base with prop roots. Adult leaves usually 20-30 times longer than wide, up to 3 m × 9 cm, margins and dorsal midrib armed with usually forwardly directed, very sharp prickles 5-10 mm long, apex gradually narrowed to an elongated flagella; youngest leaves erect, older ones drooping from the midpoint, glaucous, parallel veins 40-160 but not prominent. Male inflorescence 30-60 cm long, usually with 5-11 spikes 5-10 cm long; bracts less than 30 cm long; phalanges 10-15 mm long, bearing 19-26 stamens with filaments 0.5-2 mm and anthers 2-3.5 mm long with 0.5 mm long pointed apex. Female inflorescence usually with one single head on peduncle 10-30 cm long; bracts subfleshy, navicular with prickly midrib and margins; head globose to ellipsoid, 15-20(-30) cm × 12-18(-20) cm, containing (26-)50-70(-143) carpellate phalanges (and each cluster pentagonal or hexagonal); phalanges 3-8 cm × 2-5 cm, composed of 4-10 concentrically arranged, fused carpels; stigma U- or V-shaped. Syncarp drooping, orange-red, carpel clusters free from each other but tightly crowded, endocarp red-brown. Seed fusiform to obovoid, 10-12 mm long, with white, soft endosperm.

P. tectorius . A pyramidal branched tree up to 8 m tall, with prickly prop roots up to 1 m long; trunk with brown to grey bark. Leaves 1-1.7 m × 6-8 cm, margins with backward directed prickles, apex gradually narrowed to an elongate flagella; midrib at underside also bearing similar prickles except in lower fifth; longitudinal veins 120-150 per leaf. Male inflorescence spicate with a raceme of about 6 spikes, each one subtended by a white, fragrant, navicular bract; spike cylindrical, 4-11 cm × 2 cm, composed of numerous staminal phalanges, each with a sterile base, upper part densely covered with about 18 stamens of which the basifixed anthers are longer than the filaments and end in a small point. Female inflorescence a solitary head, pendulous, subglobose-ellipsoid, obscurely trigonous, about 17 cm × 14 cm, composed of about 108 carpellate phalanges; phalanges 5 cm × 3-4 cm, 5-6-angled, 5-7-celled, apical 15 mm free. Syncarp with upper mesocarp of fruiting carpels cavernose-medullose-fibrous, about 12 mm long, lower mesocarp fibrous-fleshy, about 20 mm long; endocarp 2-3 mm thick, bony, red-brown.

Growth and development

The natural propagation, dispersal, growth and development of many Pandanus species are not known. Growth of cuttings is often rapid, with establishment of a modest trunk (20-30 cm) and a rosette of large leaves in 3 years. Seed germination is often very slow. Seeds germinate within the bony endocarp with the seedlings exiting via the germination tube at the base of the drupe. Seedlings tend to produce erect trunks, while plants grown from cuttings may be permanently decumbent. Trees raised from cuttings bear fruits 2-3 years earlier than trees raised from seed. As a monocotyledon, Pandanus lacks secondary thickening-growth by means of a vascular cambium, but it is unusual because it is often branched. Flowering is very short (one day), and when depleted of pollen the inflorescence decays within 3-4 days. In general, male plants are rare and much smaller than female plants, and in sexual propagation pollination is mainly by wind but possibly also by small insects. In several species, e.g. P. dubius Sprengel, P. furcatus , P. odoratissimus and P. tectorius , female trees grown far from their native populations produce viable seed, which appear to be apomictic. P. tectorius is a facultative apomict, with asexual reproduction occurring in the absence of pollination. P. kaida plants in Peninsular Malaysia are apparently all staminate, though they seldom flower. Pandanus syncarps are usually dispersed by birds, mammals or water currents.

In P. odoratissimus planted for kewda products in India, flowering of male plants starts 3-4 years after planting of cuttings or suckers. The inflorescences mature in about 2 weeks and a fully grown male tree produces 30-40 inflorescences per year. Syncarps of P. odoratissimus can be dispersed by currents because they are buoyant due to the drupes' fibrous mesocarp and the empty space around the seeds. However, germination is reduced by immersion in sea water.

P. tectorius develops according to Stone's model, characterized by continuous growth of the meristem of the orthotropic trunk, which produces orthotropic branches either continuously or diffusely, and with further branches developing sympodially below terminal inflorescences. Pollination in P. tectorius is by wind. The buoyant syncarps of P. tectorius are mainly dispersed by means of sea currents, but dispersal by crabs, birds and flying foxes has also been reported. P. tectorius displays a wide variety of fruit shapes and sizes. In swamp populations of P. tectorius in Fiji, plant ages were estimated on the basis of leaf production, stem and branch growth and the number and spacing of leaf and peduncle scars. The following growth and development patterns were deduced from these estimates: a semiprostrate juvenile phase of 4.5-9 years is followed by erect trunk growth for about 5-12 years and a flowering phase lasting 40 years or more. Male plants form about 30 branches and flower annually, whereas female plants form about 15 branches and flower biannually. Each syncarp has about 75 phalanges, each containing up to 8 embryos but the modal number is 2.

Other botanical information

Together with Freycinetia Gaudich. and Sararanga Hemsley, Pandanus forms the palaeotropical plant family Pandanaceae which comprises 800-900 species. Pandanus is the largest genus and its infrageneric classification is still in progress. It has been tentatively divided into 8 subgenera, each of which with one or more sections. P. tectorius is the type species of the genus Pandanus and, together with P. odoratissimus , it is classified in subgenus Pandanus , section Pandanus ; P. atrocarpus is placed in subgenus Acrostigma , section Acrostigma ; P. furcatus is placed in subgenus Rykia , section Rykia ; and P. kaida belongs to subgenus Rykia , section Kaida .

According to some taxonomists, P. odoratissimus is included in P. tectorius but here the view of B.C. Stone is followed that they are separate species. The two species probably hybridize where they meet. P. odoratissimus is rather variable and many varieties and forms have been distinguished. It is notable for its often very large leaf spines, which are generally white or very pale, whereas the leaf spines of P. tectorius tend to be fairly small and green. There seems to be, however, a mutant spineless form of P. odoratissimus which is very difficult to distinguish from the spineless P. tectorius var. laevis , and the two may be used in the same manner. P. tectorius is also highly variable and it seems better to consider it as a still unravelled complex. Numerous names have been used to describe the variability within the complex, which has resulted in numerous species names for local populations which have been selectively grown and developed into more or less distinct cultivars, varieties or forms. The best known of these in South-East Asia is P. tectorius var. laevis (synonyms: P. inermis Reinw., P. laevis Kunth, and P. spurius Miquel), known as "pudak" or "putat" and distinguished by its spineless leaves. Its leaves are somewhat more fragile and less durable than those of other cultivars and are employed for finer goods. Other cultivars of P. tectorius include the forms known in horticulture as " P. baptistii " (leaves unarmed and variegated), " P. sanderi " (leaves armed, yellow-striped), " P. variegatus " (leaves armed, variegated with white) and " P. veitchii " (leaves armed, white-striped). These four forms can probably be grouped under " P. tectorius var. sanderi hort".

Other important South-East Asian Pandanus spp. include P. brosimos Merr. & Perry, P. conoideus Lamk and P. leram Jones ex Fontana, all three valued especially for their edible fruits or seeds, and P. amaryllifolius Roxb., the leaves of which are mainly used for food flavouring. In Burma (Myanmar) the dry drupes or phalanges of P. scopula Warb. are used as small brushes, after the exocarp has sloughed off or decayed, leaving the basal mesocarp fibres.

Ecology

P. atrocarpus is found in edges of woods in lowland swamps, often together with Pholidocarpus Blume palms. P. furcatus is a forest species, occurring in humid, shaded sites. In India it can form dense impenetrable thickets; in Java it is locally abundant but scattered, from sea-level up to 1700 m altitude. P. kaida is cultivated in humid tropical regions, at low altitudes and in monsoon zones. P. odoratissimus and P. tectorius have similar ecological requirements. They are found on sandy beaches, in littoral thickets, on the edges of brackish marshes and mangroves and inland along watercourses at low altitudes. Rainfall should be high. They can grow on a wide range of soils, but heavy, poorly drained loams are not suitable.

Propagation and planting

Pandanus is usually propagated vegetatively by sucker shoots (axillary branches detached as plantlets), stem segments or full-sized stems. Cleanly removed from the leaf axils, the sucker shoots can be planted straight away or rooted first in a sandy medium. Alternatively, stems with slightly developed prop roots are cut, the leaf crown trimmed but not cut off, and the cuttings inserted obliquely in the medium. Pandanus may also be propagated by seed, but seeds should be soaked for 24 hours before planting. Seedlings develop more rapidly from previously weathered drupes or syncarps, which suggests that removal of the exocarp and perhaps scarification of the outer endocarp may accelerate germination. Germination may take several months or even a year for some Pandanus spp. The recommended planting distance for P. odoratissimus in the Philippines is 2 m × 2 m, with suckers 40-45 cm tall planted out in holes 20-25 cm deep and 15-20 wide. However, Pandanus is seldom grown in regularly spaced stands, and domestic plantings tend to consist of a few plants intermixed with other species. A typical Malaysian homestead may have a dozen small plants of P. amaryllifolius , a few clumps of P. kaida Kurz, a single decorative plant of one of the variegated Pandanus forms, and if near the sea, some possibly wild or semiwild clumps of P. tectorius or P. odoratissimus . In Java pandans are also planted in fields, in hedges around fields and homesteads, and along roads, usually at a spacing of 1-2.5 m. In the Philippines Pandanus is intercropped with coconut palms.

Husbandry

In Indonesia some weeding may be done in the first year after planting Pandanus , but usually husbandry is minimal. In the Philippines it is recommended that plantations of P. odoratissimus be weeded every 3 months during the first year after planting and every 6 months during the second and third year, and that organic fertilizer be applied. It is also recommended that dead material be removed to prevent fire, and that old or unproductive trunks and branches be thinned or cut to promote the growth and development of axillary shoots.

Diseases and pests

Few diseases and pests afflict Pandanus and these seem most evident amongst cultivated plants and least among wild ones. In P. odoratissimus in India a leaf blight caused by Alternaria alternata (synonym: Alternaria tenuis ) has been recorded. The fungus covers large spots, which turn black, and perforations may appear, leading to premature defoliation and scanty flowering. A leaf blight caused by Botryodiplodia theobromae has also been recorded in India, the symptoms being yellowing of older leaves from the tip to the middle and the occurrence of coalescing yellow patches leading to leaf shedding.

Predation by large insects may lead to early leaf fall. Leaf miners do some damage, and occasionally large beetle larvae which consume the seed may be encountered in the endocarp chamber.

Harvesting

In Tangerang (West Java) harvesting of P. odoratissimus and P. tectorius usually starts when plants are 2.5-3 years old, when the leaves are 0.75-1.5 m long. When the plants are about 10 years old, leaf production and quality decrease and they are usually replaced. In Tasikmalaya (West Java), however, trees reportedly remain in use for 60 years without loss of quality. In the Philippines leaf harvesting of P. odoratissimus starts at 3 years after planting. Here it is recommended that 8-10 leaves per branch per month be harvested and that good quality, middle-aged, uniformly light green leaves be selected. In India the male inflorescences of P. odoratissimus are simply plucked by breaking them off using a hook attached to a stick.

Yield

No information exists on leaf or fibre yields of Pandanus . In India mature P. odoratissimus plants produce approximately 15-40 male inflorescences per plant per year. From 1000 inflorescences about 18 kg of kewda water is obtained, whereas about 100 000 inflorescences are needed to produce 1 kg of kewda oil, as the oil yield is only 0.03%.

Handling after harvest

For the production of weaving material from P. odoratissimus and P. tectorius a leaf is usually cut, dried slightly, and the marginal spines, where present, are removed. The leaves are then split into two by removing the midrib, and the halves are cut into strips. These strips are then made supple by pulling them over a bamboo, or by rolling or beating. Then they may be soaked in water, after which they are bleached in the sun. They may be dyed, often with simple stains such as crystal violet, resulting in colourful and multicoloured articles. In Tangerang leaves intended for finer work are cut off and the spines and midrib are removed. A pile is made of 25-30 leaves which are subsequently cut to equal length and made into strips. Water is expressed from these strips by means of a piece of bamboo. The strips are bundled, boiled for about an hour, placed in, preferably running, water for about 12 hours and dried. Leaves intended for coarser work are usually not boiled, but only pounded and dried. In Tasikmalaya the spiny leaf margins are removed first and the leaf strips are split off, until only the midrib with some thick leaf material remains. The strips are boiled, placed in running water, and spread in the sun for drying and bleaching. For the preparation of "sabotan fibre" from P. odoratissimus in the Philippines the spiny margins and midribs are removed, after which the leaves are divided into strips. This may be done with a device called a "sizer", made of 6 or more sharp blades mounted on a wooden plane and spaced 0.5 cm apart. Excess water is removed by drawing the strips tightly around a piece of wood or by a device called a "pounder", in which the strips are pressed between 2 wooden planes and gradually pulled through. After this the pounded strips should be air-dried for a day in a shaded place and bleached in the sun to produce a uniform white colour. The strips should not be sun-dried immediately after pounding, because this would result in discolouring. Finally the strips are sorted according to length and tied in bundles of 600-800 strips. To obtain weaving material from the leaves of P. atrocarpus on Bangka, the spines are removed by moving a sharp knife against the direction of the spines. After removing the tip, the leaves are made supple over a fire, pulled flat, folded, beaten and cut into strips of the desired width. These strips are tied together in bundles of 10, beaten, soaked, dried and trimmed, after which they are ready for weaving. Elsewhere, the leaves are simply dried in the sun before they are divided into strips. For the production of mats, the leaves of P. atrocarpus are dried over a low fire, placed in the sun for bleaching, and tacked together with split bamboo. Weaving material from the leaves of P. furcatus is prepared in the same way as that of P. atrocarpus .

Kewda attar is prepared from P. odoratissimus by distilling the ripe inflorescences for 4-5 hours. Prior to distillation, the bracts are removed from the fresh inflorescences. About 500-1000 inflorescences, each cut into 3-4 pieces, are put in a large copper still pot and water is added (60 l per 1000 inflorescences). The vapour is absorbed in sandalwood oil. Several grades are prepared depending on the number of inflorescences distilled per kg sandalwood oil, normally 1000-10 000, but sometimes up to 100 000. For cheaper grades, refined liquid paraffin ("white oil") is sometimes used instead of sandalwood oil. It is not only cheaper, but also absorbs more kewda aroma per inflorescence than sandalwood oil. However, the aroma retention is worse. Ripe, cream-coloured inflorescences give higher perfume yields of better quality than immature ones. Kewda water is obtained by simply distilling the inflorescences in water only. Kewda oil is very soluble in water and cannot be separated from the distillate by ordinary physical means. It may be prepared by extracting the flowers with a solvent, precipitating the fatty matter with alcohol and distilling the absolute under reduced pressure.

Genetic resources and breeding

Pandanaceae are well known for their general endemism which is sometimes very narrow; thus many species are threatened with extinction. Habitat destruction and collection of fruits and leaves from the wild for economic exploitation endanger many Pandanus spp. Germplasm collection is needed. Plantations are recommended for economic exploitation of the most useful Pandanus spp. The only breeding activities carried out so far have been by local selection, which has led to the establishment of numerous local cultivars.

Prospects

Pandanus spp. will remain primarily household or village plants with domestic and local barter value in Malesia, though a small cash market has developed for articles destined for sale to tourists. Ingenuity in discovering new uses for Pandanus fibres, fruits, seeds and flavourings could enhance their value. Their use as a windbreak and soil conservation plant in coastal regions may offer prospects. The prospects for P. odoratissimus as a source of kewda products in India are promising.

Literature

Cox, P.A., 1990. Pollination and the evolution of breeding systems in Pandanaceae. Annals of the Missouri Botanical Garden 77(4): 816-840.
Doydora, U., 1997. Pandan farming for fiber production. Workshop to Produce an Information Kit on Sustainable Livelihood Options for the Philippines, Silang, Cavite, the Philippines, 25 August 5 September 1997. Sustainable Livelihood Options for the Philippines 1: Upland Ecosystem (an information kit). Department of Environment and Natural Resources & International Institute of Rural Reconstruction. Diliman, Quezon City, the Philippines). pp. 4856.
Dutta, P.K., Saxena, H.O. & Brahmam, M., 1987. Kewda perfume industry in India. Economic Botany 41(3): 403-410.
Hofstede, H.W., 1925. Het pandanblad als grondstof voor de pandanhoedenindustrie op Java [The pandan leaf as raw material for the pandan hat industry on Java]. Doctorate thesis, Technical University Delft, the Netherlands. 101 pp.
Stone, B.C., 1974. Towards an improved infrageneric classification in Pandanus (Pandanaceae). Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 94(4): 459-540.
Stone, B.C., 1978. Revisio Pandanacearum. Part 1. Pandanus subgenera Coronata Martelli and Acrostigma (Kurz) Stone, Flora Malesiana, Precursores. Federation Museums Journal 23 (New Series): 1-73.
Stone, B.C., 1981. Pandanaceae. In: Dassanayake. M.D. & Fosberg, F.R. (Editors): A revised handbook to the flora of Ceylon. Vol. 3. Amerind Publishing Co., New Delhi, India. pp. 293-320.
Stone, B.C., 1983. Pandanaceae. In: Leroy, J.-F. (Editor): Flore du Cambodge, du Laos et du Viêt-nam [Flora of Cambodia, Laos and Vietnam]. Vol. 20. Muséum National d'Histoire Naturelle, Paris, France. pp. 3-48.
Stone, B.C., 1991. Pandanus Parkinson. In: Verheij, E.W.M. & Coronel, R.E. (Editors): Plant resources of South-East Asia No 2. Edible fruits and nuts. Pudoc, Wageningen, the Netherlands. pp. 240-243.
Stone, B.C., 1994. A note on Pandanus (Pandanaceae) in Taiwan. Botanical Bulletin of Academia Sinica 35(2): 129-131.

Authors

M. Brink & P.C.M. Jansen