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The most widely known economic products of theAnnonaceae family in the tropics are its edible fruits, especially the fruits of the genusAnnona (custard apple). One of the most important of these isAnnona reticulata (West Indian bullock’s-heart), which is well adapted to hot climates and produces fruit only three years after planting. The common name is suggestive of the round-to-heart-shaped appearance and size of the fruit, which may be up to 12 cm (5 inches) in diameter and length when ripe. When the fruit is ripe and the yellow-brown skin has begun to blacken, its white to cream-coloured pulp becomes sweet and aromatic, and it resemblesice cream when chilled.

Annona squamosa (sweetsop, or sugar apple), although native to northernSouth America,Central America, and the Caribbean region, is even more widelycultivated and highly esteemed inIndia and Pakistan. The conical fruits break into segments when ripe and expose a cream-coloured sweet pulp in which dark brown glossy seeds are embedded. Among the natives of the tropics, the sugar appletree is reputed to be of medical value. Tea made from the roots is highly purgative, while that made from the leaves is a mild laxative and is also considered to have a general tonic effect on thedigestive tract. Poultices of the leaves are used in dressing infected wounds.

Thecherimoya is the fruit of a rather small tree,Annona cherimola, which is native to the cool (but frost-free) mountain valleys of Peru and Ecuador. Although it is grown in southern Florida, it does not produce fruit well there because of the high humidity; it is currently commercially grown on a small scale in southern California. The fruits, however, are quite perishable and ferment readily. Like the sugar apple, it is now established in the Old World tropics. Although the fruit does not break into segments when ripe the way that the sugar apple does, the flesh is of a more creamy consistency (it contains up to 18 percent sugar) and has fewer seeds. Under ideal conditions, the fruit mayattain a large size, weighing up to 7 kg (16 pounds).

Annona muricata (soursop, or guanabana) also is native to the American tropics; it probably originated in Brazil or theAntilles. In a commercial setting, it must be pollinated by hand. The fruit weighs between 1.3 and 3.6 kg (3 to 8 pounds) and reaches 15 to 20 cm (6 to 8 inches) in length. It is tapering and heart-shaped, and the green skin is covered with spiny protuberances. The aromatic flesh, white and somewhat fibrous, is strained to make custards and ice cream; the acidulous juice is usuallyextracted to make a refreshing drink, which has been described as a combination of the flavours of strawberries, pineapples, and cinnamon. The fruit is approximately 12 percent sugar, mostlyglucose, and is a good source ofniacin,riboflavin, andvitamin C. The black seeds contain toxins that have a purported use locally as a repellent against parasites. The hybridAnnona squamosa ×cherimola (atemoya) apparently originated in Central America and the Antilles; the fruit contains some of the best features of both parents. Extracts of the root and leaves have a laxative effect, and poultices of the leaves are used to dress infected wounds.Annona glabra (alligator, or pond, apple) grows plentifully in the FloridaEverglades and on theFlorida Keys, where its fruits have been described as “edible but not very palatable.” The tree’s prime use in Florida is as a rootstock forA. reticulata andA. squamosa when the soil is deep and sandy.

Other species ofAnnona that produce comparativelyinferior fruit but are eaten locally includeA. montana (mountain soursop), from theWest Indies and South America;A. longiflora, from Mexico;A. paludosa, from Brazil;A. testudinea, from Honduras;A. nutans, from Paraguay;A. senegalensis, from East and West Africa; andA. diversifolia (ilama), which was first cultivated long ago by theAztecs of Mexico.

Two species ofRollinia (R. mucosa andR. pulchrinervis) have edible fruits that reach 10 cm (4 inches) in length and bear some resemblance to those of the soursop, except that the spines are softer and more blunt.Rollinia mucosa is a large tree native to the West Indies and northern South America, whereasR. pulchrinervis is native to theAmazon River basin. Both species are referred to by the common namebiriba, and both are widely cultivated, particularly throughout Brazil, for their delicious fruits.

Asimina triloba (pawpaw) is native to easternNorth America and produces edible fruits of various sizes, colours, and palatabilities. (Carica papaya, orpapaya, of the family Caricaceae, is also sometimes known as pawpaw.) Two general types ofAsimina triloba have been observed: large, yellow-fruited, highly flavoured, and early-ripening; and relatively small, white-fleshed, mild-flavoured, and late-ripening. A number of selected clones (groups of plants of identical genetic makeup that are vegetative divisions of one plant),propagated by grafting, are cultivated, principally in southern Pennsylvania, Ohio, Illinois, and Indiana (where the yellowish fruits are referred to asIndiana bananas). Analcoholic beverage may be made from the fruit.

Chemicals

Cananga odorata (ylang-ylang) ranges from the tropical parts of eastern India through Malaysia to the Philippines. The name of theplant, which means “flower of flowers,” derives from the exceedingly delicate and evanescent fragrance of the yellowish green, bell-shaped flowers. The fragrance is highly valued in the manufacture of perfumes.Ylang-ylang, or cananga, oil is derived by simple distillation from the petals of fully opened flowers. Although the tree blossoms throughout the year, the flowers picked in May or Juneyield the highest amounts of cananga oil. Long known to the peoples ofEast Asia, this oil first reached Europe about 1864.

In the upper Amazon region, Indian tribes use an extract from the treeUnonopsis veneficiorum to tip their poison blowgun darts and arrows; this substance has a similar paralyzing effect on humans and other animals to that caused bycurare, which is obtained from the genusStrychnos of the familyLoganiaceae.