Agroforestree Database

Local names:
 Arabic (fafay,babaya), Bengali (pappaiya,papeya), Burmese (thimbaw), Creole (papayer,papaye), English (bisexual pawpaw,pawpaw tree,melon tree,papaya), Filipino (papaya,lapaya,kapaya), French (papailler,papaye,papayer), German (papaya,melonenbraum), Hindi

Carica papaya is an evergreen, tree-like herb, 2-10 m tall, usually unbranched, although sometimes branched due to injury, containing white latex in all parts. Stem cylindrical, 10-30 cm in diameter, hollow with prominent leaf scars and spongy-fibrous tissue. Has an extensive rooting system.

Leaves spirally arranged, clustered near apex of trunk; petiole up to 1 m long, hollow, greenish or purplish-green; lamina orbicular, 25-75 cm in diameter, palmate, deeply 7-lobed, glabrous, prominently veined; lobes deeply and broadly toothed. 

Flowers tiny, yellow, funnel-shaped, solitary or clustered in the leaf axils, of 3 types; female flowers 3-5 cm long, large functional pistil, no stamens, ovoid-shaped ovary; male flowers on long hanging panicles, with 10 stamens in 2 rows, gynoecium absent except for a pistillode; hermaphrodite flowers larger than males, 5-carpellate ovary; occurrence depends on the season or age of the tree.

Fruits large, cylindrical, with fleshy orange pulp, hollow berry, thin yellowish skin when ripe, varied. Fruits formed from female flowers are oblong, spherical, pear-shaped; from hermaphrodite flowers, long, obovoid or pyriform. Seeds numerous, small, black, round, covered with gelatinous aril. Small latex vessels extend throughout the tree and are particularly abundant in fruit that has reached full size but has not yet begun to ripen.

The generic name is from the Latin ‘carica’, meaning ‘edible fig’, on account of the similarity of the leaves.

Ecology

C. papaya grows satisfactorily in a wide range of areas from the equatorial tropics to temperate latitudes. However, it must be grown in warm, sunny sites sheltered from wind; preferably below 1500 m. Strong winds are detrimental, particularly on soils that cannot make up for large transpiration loss. C. papaya is not frost hardy; exposure to frost or cold wind usually results in leaf damage and subsequent death of the tree. Roots are very sensitive to waterlogging, and even short periods of flooding can kill the plant.

Native range
Costa Rica, Mexico, United States of America

Tree management

Weeds must be controlled, especially during the initial stages of establishment. Herbicides, hand weeding, mulching and use of cover crops are some of the practical methods used in the control of weeds. Even though fairly resistant to drought, C. papaya requires a constant water supply. C. papaya is very responsive to fertilizers, and yield can be significantly improved by proper fertilization. Control of pH is also very important. Fruit production begins within a year of planting and is continuous thereafter. C. papaya produces 30-150 fruits/year. As the fruit is formed in the leaf axils, plants must be kept growing continuously for maximum yield. Mature trees may be rejuvenated by cutting back to 30 cm above the ground. The latex should be tapped at least once a week.

Seeds have orthodox storage behaviour; viability can be maintained for up to 3 years in hermetic air-dry storage at 12 deg. C. There are 300-700 seeds in each fruit and approximately 20 000 seeds/kg.

C. papaya grows satisfactorily in a wide range of areas from the equatorial tropics to temperate latitudes. However, it must be grown in warm, sunny sites sheltered from wind; preferably below 1500 m. Strong winds are detrimental, particularly on soils that cannot make up for large transpiration loss. C. papaya is not frost hardy; exposure to frost or cold wind usually results in leaf damage and subsequent death of the tree. Roots are very sensitive to waterlogging, and even short periods of flooding can kill the plant.

C. papaya is usually grown from seed, which germinates in 2-4 weeks under favourable conditions. Gelatinous covering is removed by rubbing the seed on cloth or a sheet of rubber. The seed is washed and dried on paper out of the sun. Often seedlings are raised in nurseries using flats with sterilized potting soil, placed in partial shade when seeds are sown. After 2 weeks, the seedlings are moved into full sunlight and a week later transferred to pots. Direct sowing in bottomless pots eliminates some transplanting problems. Seedlings are planted out in the field 6-8 weeks later at a density of 1000-2000 plants/ha with recommended spacing of 2.5-3 x 2-3 m, or 4.5 x 2 m where machinery is used. Direct sowing in the desired field is a simpler method; however seeds should be protected from pests such as ants. Since there is no reliable method of determining sex in papaya until 1st flowering occurs, at least 4-5 seedlings should be planted per planting hole.

Vegetative propagation is possible but rarely practised. Because the scarcity of scion material from mother plants makes it expensive, it is reserved only for experimental purposes. The top of the tree is broken off to induce development of shoots, which can then be used for cleft grafting or making cuttings.

  Ripe papaya is a favourite breakfast and dessert fruit that is available year-round. It can be used to make fruits salads, refreshing drinks, jam, jelly, marmalade, candies and crystallized fruit. Green fruit is pickled or cooked as vegetable or as a substitute for applesauce. About 60% of the ripe fruit is edible. The approximate content per 100 g edible portion is water 86.6 g, protein 0.5 g, fat 0.3 g, carbohydrates 12.1 g, fibre 0.7 g, ash 0.5 g, potassium 204 mg, calcium 34 mg, phosphorus 11 mg, iron 1 mg, sodium 3 mg, vitamin A 450 mg, vitamin C 74 mg, thiamine 0.03 mg, niacin 0.5 mg, and riboflavin 0.04 mg. The energy value is 200 kJ/100 g. Major sugars are sucrose (48.3%), glucose (29.8%) and fructose (21.9%). In Java, a sweetmeat is made from the flowers. Young leaves are sometimes eaten.

Medicine:  Carapine, an alkaloid present in papaya, can be used as a heart depressant, amoebicide and diuretic. The fruit and juice are eaten for gastrointestinal ailments; a fresh leaf poultice is used to treat sores. The fresh root with sugarcane alcohol can be taken orally or as a massage to soothe rheumatism. A flower decoction is taken orally for coughs, bronchitis, asthma and chest colds. In some countries, the seeds are used as an abortifacient and vermifuge.

Latex or rubber:  In some countries, C. papaya is grown in sizeable plantations for the extraction of papain, a proteolytic enzyme present in the latex, collected mainly from green fruit. Papain has varied uses in beverage, food and pharmaceutical industr