Palaquium

Gutta Percha ( Palaquium gutta )

The Guttaperchabäume ( Palaquium ) are a species-rich plant genus of the family of Sapotengewächse ( Sapotaceae ). They are widespread in the tropics of Southeast Asia and northern Australia. The most familiar type is the Gutta Percha ( Palaquium gutta ), whose dried- milk juice is the important raw material gutta-percha.

Description

Palaquium species grow as evergreen trees and reach depending on plant height 5-30 meters, in part, in sizes up to 1 meter. They contain milky sap (latex). The alternate and distichous or arranged or several together standing leaves are simple, leathery and 8 to 25 cm long. On the top they are glossy green on the underside often yellow or gray-green. The small to very large stipules fall off early.

The flowers appear singly or in groups together along the branches, or in short terminal inflorescences. Are conspicuous bracts at the base of Blütenstandsschäfte. There are two circles with a total of usually six (four to seven) sepals present. There are four to six petals present. The standing in two or three circuits in total, usually 12 to 18 ( 8 to 36 ) fertile stamens are inserted into the corolla tube. The stamens are long. In contrast to other genera of the family no staminodes are present. Most six ( five to eleven) carpels are fused into a hairy superior ovaries. The carpel only a anatrope, hanging ovule is present.

3 to 7 cm wide elongated to ellipsoidal berry contains one to four seeds. Scar covers half of the surface of the seed.

Dissemination

The Palaquium species are widespread in the tropics of Southeast Asia and northern Australia. The occurrence rich north to Taiwan, south to the Malay Peninsula and east to the Solomon Islands.

System

The genus Palaquium 1837 set by Francisco Manuel Blanco in Flora de Filipinas, p 403. 1903 was set as the lectotype Palaquium lanceolatum Blanco. Synonyms for Palaquium Blanco are: Croixia Pierre, Dichopsis Thwaites, Galactoxylon Pierre, trust Bella Pierre. The genus belongs to the tribe Palaquium Sapoteae in the subfamily Sapotoideae in the Sapotaceae family.

There are about 110 Palaquium species ( selection):

  • Palaquium amboinense Burck
  • Palaquium burckii H.J.Lam
  • Palaquium calophyllum ( Teijsm. & Binn. ) Pierre: Syn: Isonandra calophylla Teijsm. & Binn.
  • Palaquium formosanum Hay.
  • Gutta Percha ( Palaquium gutta ) ( Hook. ) Baill. Syn.. Isonandra gutta Hook, Isonandra gutta oblongifolia var de Vriese, Palaquium oblongifolium ( Burck ) Burck
  • Palaquium hexandrum ( Griff. ) Baill.
  • Palaquium leiocarpum Boerl.
  • Palaquium luzoniense ( Fern. - Vill. ) S.Vidal: syn: Dichopsis luzoniensis Fern. - Vill.
  • Palaquium maingayi ( C.B.Clarke ) King & Gamble
  • Palaquium obovatum ( Griff. ) Engl
  • Palaquium philippense ( Perr. ) CBRob. Syn: Chrysophyllum philippense Perr.
  • Palaquium polyandrum C.B.Rob.
  • Palaquium ridleyi King & Gamble
  • Palaquium rostratum ( Miq. ) Burck
  • Palaquium stellate King & Gamble

Use

The gutta-percha, the dried milk of the Guttaperchabaumes ( Palaquium gutta ), is an important raw material, which was formerly used for cable insulation and is still used among other things as filling material in dentistry.

The berries are edible in several species.

Many species of the genus also provide a valuable wood.

Swell

  • Shugang Li & TD Pennington: Sapotaceae in the Flora of China, Volume 15, p 206: Palaquium - Online. ( Description section )
Asterids Ovary (botany) Agricultural Research Service
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