Artocarpus heterophyllus Lamk

Artocarpus heterophyllus Lamk

Family

Moraceae

Synonyms

Artocarpus philippensis Lamk, Artocarpus brasiliensis Gomez, Artocarpus maxima Blanco, Artocarpus integer (Thunb.) Merr.

Vernacular Names

Malaysia Nangka.
English Jackfruit, jack.
Indonesia Nangka, nongko (Javanese).
Papua New Guinea Kapiak.
Philippines Langka.
Burma Peignai.
Cambodia Khnaôr.
Laos Miiz, miiz hnang.
Thailand Khanun (central), makmi (north-eastern), banun (Chiang Mai).
Vietnam Mit.
French Jacquier.

Geographical Distributions

Artocarpus heterophyllus is most probably indigenous and in the past grew wild in the rainforests of the Western Ghats, India. Since time immemorial it has been cultivated; it was introduced and became naturalised in many parts of the tropics, particularly in the Southeast Asian region.

Description

A. heterophyllus is a medium-sized, evergreen, monoecious tree up to 20(-30) m tall and 80(-200) cm in diametre, with all living parts exude viscid, white latex when injured. Its bark is rough to somewhat scaly and dark grey to greyish-brown. The crown is dense and conical when young but becomes rounded or spreading in older trees. The new shoots, twigs and leaves are usually hairless but occasionally short-haired and scabrid. The stipules are ovate-acute, measuring 1.5-8 cm x 0.5-3 cm, deciduous and leave annular scars on the twigs.

The leaves are thin leathery, obovate-elliptic to elliptic, measuring 5-25 cm x 3.5-12 cm, broadest at or above the middle, with a wedge-shaped base, entire margin or in young plants often with 1-2 pairs of lobes, which are rounded or blunt with short apex and pointed tip. The leaves are dark green and shiny above but dull and pale green underneath. The petiole is 1.5-4 cm long, shallowly grooved on the adaxial side and sparsely hairy.

The inflorescences are solitary, also borne axillary on special lateral, short leafy shoots which arise from older branches and main trunk. The male flower heads are barrel-shaped or ellipsoid, dark green, 3-8 cm long and 1-3 cm across, composed of sterile and fertile flowers which are closely embedded in a central core (receptacle) and with stalk 1.5-3.5 cm long and 0.5-1.0 cm thick, bearing annular ring near the distal end. The sterile male flowers are with solid perianth while fertile male flowers are with tubular, bilobed, 1-1.5 mm long perianth and 1-2mm long stamen. The female heads are borne singly or in pairs and distal to the position of male heads. They are cylindrical or oblong, dark green, 5-15 cm long and 3-4.5 cm across, with a distinct annulus at the top end of the stout stalk, subtended by a spathaceous, deciduous bract and 5-8 cm long. The female flowers are with tubular perianths which are fused at both ends and projecting as 3- to 7-angled, blunt or pointed, minute pyramidal protuberances with spathulate or ligulate styles and stigmas on top.

The fruit (syncarp) is barrel- or pear-shaped, measuring 30-100 cm x 25-50 cm and with short pyramidal protuberances or warts. Its stalk is 5-10 cm long and 1-1.5 cm thick. The rind is about 1cm thick, together with the central core (receptacle) inseparable from the waxy, firm or soft, golden yellow and fleshy perianths which surround the seeds.

The seeds are numerous, oblong-ellipsoid, measuring 2-4 cm x 1.5-2.5 cm, enclosed by horny endocarps and sub-gelatinous exocarps. The testa is thin leathery and the embryo is with ventral radicle, fleshy cotyledons and unequal. The endosperm is very small or absent.

Ecology / Cultivation

In its original habitats, A. heterophyllus was apparently found mainly in evergreen forests at altitudes of 400-1200 m. The tree extends into much drier and cooler climates than A. altilis (Parkinson) Fosberg and A. integer. It fruits up to latitudes 30oN and S in frost-free areas and bears good crops at 25°N and S of the equator. However, A. hetrophyllus thrives in warm and humid climates below 1000 m altitude. In fact, it has poor tolerance towards cold, drought and flood, but has moderate wind and salinity tolerance. The annual rainfall for optimal growth should be 1500 mm or more and dry season should not be too prominent. The tree can grow on different types of soil but performs best on deep, well-drained, alluvial, sandy or clay loam soils with pH 6.0-7.5.

Line Drawing / Photograph

BOT00211

References

  1. Plant Resources of South-East Asia No.2: Edible fruits and nuts .