Durian

A large evergreen tree, 25–50 m tall, with a straight trunk and dense crown. The simple alternate leaves are dark glossy green above and covered beneath with brownish stellate scales. Flowers are borne in clusters of 3–30 on old branches (cauliflory); each flower is 5–7 cm, white to cream, opens at night with a strong scent, and is pollinated mainly by nectar bats. The fruit is large, oblong to nearly round, up to 30 cm long and 1–3 kg; the thick rind (5–6 mm) is densely covered with sharp pyramidal spines and splits into five segments when ripe. The aril (flesh) is pale yellow to orange, richly sweet, creamy and smooth; each segment holds one or two large flattened seeds, edible when cooked.

The durian belongs to genus Durio (mallow family, formerly Bombacaceae) with about 30 species, at least nine of which yield edible fruit; Durio zibethinus is native to Borneo and Sumatra and is the only species traded internationally. Thailand has over 300 named cultivars and Malaysia about 100 (1987); famous ones include Monthong (Thailand) and Musang King (Malaysia). The fruit's characteristic odour comes from volatile sulfur compounds such as ethanethiol and may linger for days, so some hotels and public transport in Singapore and Bangkok ban it. In Vietnam, durians are grown mainly in Tiền Giang (Cái Bè), Bến Tre, Đồng Nai, Bình Phước and Lâm Đồng; grafted trees bear after 4–5 years, and Vietnam is a major durian exporter to China.