Artocarpus heterophyllus

Common Names: Jackfruit (English), ചക്ക (Malayalam), कटहल (Hindi), பலா (Tamil), কাঁঠাল (Bengali), Nangka (Malay/Indonesian), Langka (Tagalog), Mít (Vietnamese), ขนุน (Thai), パラミツ (Japanese), 波羅蜜/大樹菠蘿 (Chinese)
Scientific Name: Artocarpus heterophyllus Lam.
Family: Moraceae
Natural Distribution: Origin believed to be from Southwestern India (Western Ghats)
Natural Habitat: Tropical evergreen montane rainforest around 400m to 1,200m above sea level.
Description: Evergreen tree that grows to around 20m in the wild (mostly around 10m in cultivation). The leathery-glabrous dark green alternate simple leaves reach to 25cm long and 10-12cm wide (maximum). Young seedlings’ new shoots and leaves are papery and rough but as the individual matures, the leaves become glossier (or rather smoother). The rough bark is dark brownish.
Flower: The plant is monoecious but flowers are unisexual. Usually flowers just after winter (around late March in Asia). Cauliflory, pedunculated usually on mature branches. The oblong inflorescence catkin structures (male and female) emerge from bracts. Individual flowers are tiny, but the female catkins are larger than the male catkins, yellowish green in colour. Pollinated by wind and insects. 
Seeds: Oval-shaped light brown seeds are recalcitrant (must be germinated immediately or else viability is lost) and about 2.5 to 3cm. There are hundreds of seeds in one big fruit. Fruit is one of the largest in the world (is the largest tree-borne fruit), with some larger ones weighing more than 30kg. Mature fruits turn from green to rusty yellow. The fruit size varies considerably, typically around 20 to 50cm long. Exocarp (outer layer of fruit) is covered with small blunted pyramidal spikes (each spike is a carpel of a single flower) all throughout and does not inflict pain when handling with bare hands. Fruiting usually occurs in June to August in Asia, but some individuals fruit all year. 

Widely cultivated in the tropical and subtropical Africa, Americas, Asia and Australia mainly for its edible yellow sweet pulp in the fruit (each pulp contains one seed – the fruit is actually a syncarp, an aggregation of many individual true fruits). To me it has a fruity bubble-gum flavour and texture of rubber. Jackfruit are also used in some cooked dishes and the seeds can be eaten once cooked. It is perhaps the hardiest (although cold resistant, it probably cannot withstand freezing temperatures) species within the Artocarpus genus, being able to fruit in subtropical climates. Usually takes about 5-10 years to fruit from seed. The plant leaks out sticky white sap / latex when cut (leaves, stem or fruit) and sometimes the latex within the fruit makes it messy to cut it. It’s other documented uses include its timber, latex and resin. 

2018/09/15, these washed jackfruit seeds that are infected with insects. The seeds without water will dry and turn whitish (there’s actually a thin plastic-like seed coat layer that can be peeled when wet).