Pinanga (PROSEA)
Introduction |
Pinanga Blume
- Protologue: Bull. Sci. Phys. Nat. Néerlande 1: 65 (1838).
- Family: Palmae
- Chromosome number: x= 14, 16;P. coronata,P. disticha(Roxb.) Blume ex H. Wendl.: 2n= 28,P. patula: 2n= 32
Vernacular names
- Indonesia: pinang (general)
- Malaysia: pinang (general), legong (for larger species)
- Philippines: abiki (general), dasigan (Iloko), salansigang (Manobo)
- Thailand: maak
- Vietnam: cau bụi rừng.
Origin and geographic distribution
Pinanga comprises about 120 species ranging from the Himalayas and southern China to Indo-China, Thailand and the entire Malesian region. The greatest diversity is found in the per-humid areas of western Malesia.
Uses
The slender poles of Pinanga have been used as walking-sticks, spear shafts and, especially those of P. punicea , also as rafters and for walls.
Several species with attractively mottled leaves are becoming popular ornamentals. The palm cabbage (apex) of young plants is edible. The leaves are used as thatch. Young leaves of P. punicea have been used to obtain threads to weave rough textile. The kernel of several species is used for chewing, as a substitute for betel nut ( Areca catechu L.). The endosperm has been used as a dye in the batik industry. Pinanga is also applied for erosion control.
Production and international trade
Pinanga wood is used rarely and on a local scale only, as stems are usually too small.
Properties
Cortex narrow with numerous fibrous strands and occasional small vascular bundles; central cylinder with peripheral vascular bundles somewhat congested; central vascular bundles each with a well-developed fibrous phloem sheath, xylem sheathed by parenchyma only, phloem undivided, metaxylem with a single wide vessel; ground parenchyma cells somewhat transversely expanded but not lacunose; scattered fibrous strands frequent.
The wood is very strong.
Botany
Unarmed, monoecious, pleonanthic, solitary or diffusely to densely clustered, very small to medium-sized palms up to 8(-12) m tall; pole straight, slender, up to 15 cm in diameter, with conspicuous leaf scars, occasionally stilt-rooted. Leaves simple or pinnate; sheath forming a well-defined crown-shaft; petiole present or absent; leaflets 1- to several-fold, acute or lobed. Inflorescence usually borne below the leaves, protogynous, spicate or branched to 1 order; peduncular bract absent. Flowers unisexual, in spirally arranged or distichous triads or in 4 or 6 vertical rows. Male flower asymmetrical; calyx cupular with 3 often unequal lobes; petals 3, briefly joined at base, much exceeding the calyx; stamens usually 12-30, rarely 6, filaments short. Female flower globose, symmetrical, much smaller than the male one; sepals free or connate at base, imbricate, membranous; petals free, imbricate; ovary superior, 1-locular with a single ovule, stigma usually convolute, sessile or on a short style. Fruit a globose to spindle-shaped, smooth drupe. Seed usually with ruminate endosperm and basal hilum. Seedling with adjacent-ligular germination; eophyll usually bifid.
When the inflorescences of P. patula heat up, its flowers produce a musty odour and are pollinated by beetles. Seed dispersal is probably by birds.
Little is known of the botany of Pinanga . It is in need of a taxonomic revision; the last review was in 1886. It belongs to the subtribe Arecinae of the tribe Areceae within the subfamily Arecoideae .
Ecology
Pinanga is found in the understorey of primary lowland to montane rain forest, up to 2800 m altitude. Many species are found on sandstone soils, a few on limestone and ultrabasic soils. Several Pinanga species may grow sympatrically, especially in Borneo.
Silviculture Pinanga can be propagated by seed; propagation from suckers of P. coronata is difficult. Seeds of Pinanga remain viable for only 2-3 weeks and generally germinate within a few weeks after sowing. Seed of P. coronata soaked for 7 days germinates in about 13 days when kept in a polythene bag at a temperature of 35C.
Genetic resources and breeding
None of the timber-yielding Pinanga species is rare.
Prospects
Pinanga does not have any important commercial prospects.
Literature
70, 150, 163, 229, 236, 324, 430, 436, 499, 500, 785, 931, 940, 1059, 1100, 1110, 1176, 1210.