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GENERAL
CROP INFORMATION
This summary was prepared from publications by
Chia, C. L. et. al. and Tripton, T. V., et. al.
FAMILY: Caricaceae
SCIENTIFIC NAME: Carica papaya L.
ORIGIN: American tropical lowlands
DESCRIPTION
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Papaya is a short-lived perennial growing to 30 ft (9.14
m) high. Its hollow, herbaceous stem is usually
unbranched. The deeply lobed, palmate leaves are borne on
long, hollow petioles emerging from the stem apex.
Flowers occur in leaf axils. Older leaves die and fall as
the tree grows.
Papaya flowers are fragrant and have five cream-white to
yellow-orange petals 1 to 2 in (2.5 to 5.1 cm) long. The
stigmatic surfaces are pale green, and the stamens are
bright yellow.
Papaya fruits are smooth skinned. They vary widely in
size and shape, depending on variety and type of plant.
Hermaphrodite plants of commercial 'Solo' varieties in
Hawaii usually produce fruits that are pear shaped and
weigh approximately 12 to 30 oz (340 to 851 g). Female
plants of 'Solo' varieties produce round fruits. Other
papaya varieties produce variously shaped fruits, which
may weigh up to 20 lb (9.1 kg). The fruits usually
contain many seeds surrounded by a smooth yellow to
orange-red flesh that is sweet in good varieties.
Flower type. Flower type is determined by the presence or
absence of functional stamens (male parts) and stigma and
ovary (female parts). Within varieties, flower type is
usually identified by flower size and shape.
Female flowers are relatively large and rounded at the
base. They have a stigma but lack stamens. They generally
must receive pollen in order to set fruit. Pollen can be
carried by wind or by insects.
Male flowers are thin and tubular. They have perfect
structure (i.e., they contain both male and female
organs), but the small, vestigial ovary is nonfunctional.
Male flowers are usually borne on a long flower stalk
(peduncle).
Hermaphrodite flowers are intermediate between female and
male flowers in size and shape. They are less bulbous
than female flowers, but not as thin as male flowers.
They have perfect structure with functional stigma and
stamens and usually are self-pollinating.
Plant type. Three types of plants are recognized based on
flower type: female, hermaphrodite, and male.
Female plants always produce female flowers. If no male
or hermaphrodite plants are nearby to provide pollen,
female plants usually fail to set fruit. Unpollinated
female plants occasionally set parthenocarpic fruits,
lacking seeds.
Male plants are distinguished by their long flower stalks
bearing many flowers. Usually they do not produce fruit,
but on rare occasions there is female expression in the
flowers, and they may set fruits .
Hermaphrodite plants may have male flowers, hermaphrodite
flowers, or both, depending on environmental conditions
and the time of year. Hot, dry weather may cause
suppression of the ovary and the production of
female-sterile (i.e., male) flowers. This accounts for
occasional seasonal failure of hermaphrodite plants to
set fruit. Male flowers on hermaphrodite plants are borne
on short peduncles.
Hermaphrodite plants tend to produce selfpollinated
seeds, which result in relatively uniform progenies.
Seeds from hermaphrodite plants of 'Solo' varieties
characteristically produce one-third female and
two-thirds hermaphrodite plants, but no male plants are
produced.
Although hermaphrodite and female plants have similar
fruit texture and quality, female plants may be less
productive, and the round female fruits are marketed only
in small quantities in Hawaii as direct sales from
growers to consumers. Female plants are removed from
commercial orchards as soon as they can be distinguished
at flowering. In home gardens, female plants may be kept
if hermaphrodite or male plants are nearby to serve as a
pollen source.
VARIETIES Back To: Menu Bar
The 'Solo' variety is valued for its productivity,
uniform fruit shape and size, and excellent fruit
quality. 'Solo' strains are predominantly self-pollinated
and thus are highly inbred and uniform.
Three 'Solo'-type varieties are grown commercially in
Hawaii. The most important is 'Kapoho', which has
yellow-orange flesh and fruits that weigh 12 to 22 oz,
considered an ideal size for export. 'Kapoho' is adapted
to the Puna district of the island of Hawaii, where
approximately 90 percent of the state's papayas are
grown. The 'Sunrise' variety, commercially grown
primarily on Kauai, has reddish-orange flesh and larger
fruit than 'Kapoho'. 'Sunrise' is grown and marketed on a
large scale overseas, but in Hawaii its production and
export are small compared to those of 'Kapoho'. The
'Waimanalo' variety, which has yellow-orange flesh and
somewhat larger fruit than other 'Solo' papayas, is grown
and marketed almost entirely on Oahu.
USES Back
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Ripe papaya is usually consumed fresh as a breakfast or
dessert fruit; it can also be processed and used in a
variety of products such as jams, fruit juices, and ice
cream. Papaya is also consumed as a dried fruit. Culled
fruits can be fed to pigs and cattle.
Papaya is an ingredient in a variety of cuisines
throughout the world. Unripe fruits and leaves are
consumed as vegetables. Papaya seeds are also used as an
ingredient in salad dressings.
Papain is a milky latex collected by making incisions in
unripe papayas. The latex is either sun-dried or
oven-dried and sold in powdered form to be used in beer
clarifiers, meat tenderizers, digestion aids, wound
debridement aids, tooth-cleaning powders, and other
products. The solo papaya is not a good
variety for papain production due to its low yield of
papain.
The papaya fruit is about 88.8% water, 9.8 %
carbohydrate, 0.8% fiber, 0.6% protein, 0.6% ash and 0.1%
fat. A 100g (3.5 oz.) serving of papaya has 39 calories,
compared to banana's 92 calories. Papayas also contain
16% more vitamin C than oranges and are a good source of
vitamin A (about half of that contained in mango).
Consumption of the fruit is reported to aid digestion
because of the papain content.
PROPAGATION Back To: Menu Bar
Papaya is grown from seed. Dry seed may be stored for a
year or more in airtight refrigerated containers. Fresh
seeds will usually germinate in 10 to 14 days.
Germination can be improved by removing the gelatinous
outer seed coat (sarcotesta) before drying.
Seeds are sown either in containers or directly in the
ground. Transplanting container-grown plants is usually
limited to areas where there is dependable rainfall or
supplemental irrigation. When direct-sowing, 10 to 15
seeds are sown 1/4 to 1/2 in (63 to 127 mm) deep in each
planting hole. To ensure adequate stands in lava lands,
approximately 0.5 cubic feet (14.16 cubic dm) of soil
should be placed in each planting hole. The soil helps to
retain fertilizer nutrients and moisture.
SOIL TYPES and
LOCATION Back To: Menu Bar
Papaya grows well on many types of soil, but they must be
adequately drained. Restricted soil drainage promotes
root diseases. Most commercial production in Hawaii is on
porous aa lava. Production on other soil types is limited
to low rainfall areas where restricted drainage is less
likely to cause problems. Heavy clay and pahoehoe lava
soils should be avoided. Soil pH near neutral (pH 6.0 to
7.0) is preferred.
Soil categories used for commercial production vary from
island to island. On Hawaii, both aa lava and soils are
used. On aa lava lands, additional soil is usually
brought in and placed in the planting hole. The soils
used for papaya on the island of Hawaii have a high
preplant phosphorus fertilizer requirement. These soils,
as well as the organic soils derived from lava, are
usually acidic, and liming may be necessary. On Kauai the
soils used for papaya usually require liming and high
levels of phosphorus fertilization. On Oahu the soils on
which papaya is grown are often poorly drained.
Papaya grows best in warm areas below 500 ft (152 m)
elevation. Fruit production and quality decline at higher
elevations, where cooler temperatures cause flower drop
and cat-faced (carpelloidic) fruits. (Carpelloidy is the
abnormal development of stamens into fleshy structures.)
Papaya can tolerate moderate winds if well rooted. Forty
to 60 in (102 to 152 cm) of rainfall evenly distributed
throughout the year is adequate for growth. With higher
rainfall, soils should be porous and well drained.
Planting on slopes or on raised hills helps to prevent
waterlogging.
CULTURAL PRACTICES
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Seedlings are thinned to five or six plants per hole six
weeks after planting. Six weeks later, three vigorous
seedlings per hole are selected, and the others are
removed by cutting them off at ground level. When flower
buds appear five to seven months after planting, the
female plants can be distinguished and removed, keeping
one hermaphroditic plant per hole. Tree spacing varies
from 5 to 7 ft (1.52 to 2.13 m) between plants in rows 8
to 11 ft (2.44 to 3.35 m) apart.
Fertilizer schedules vary with soil type, climate, and
season. The general suggestions for fertilizer
applications given here are based on commercial practices
but can be used by the home gardener. In commercial
plantings, fertilizers are either broadcast onto the soil
surface within the leaf drip zone or applied through drip
irrigation lines. In home gardens, fertilizers are
usually broadcast on the soil surface. Organic matter
mixed with the soil before planting and applied afterward
to the soil surface as mulch helps to ensure good rooting
conditions and a supply of micronutrients.
Preplant fertilizer applications. On acid soils with a pH
of less than 5.5, a preplant lime application is usually
recommended to raise the pH and provide calcium.
Dolomite, which provides both calcium and magnesium, may
be substituted for part of the lime requirement. These
soil amendments should be thoroughly mixed with the soil
in the rooting zone before planting
Phosphorus applied before planting should be thoroughly
mixed with the soil or placed in a band away from the
seeds. Application rates depend on soil type. For soils
that do not have a high phosphorus requirement, a
preplant application of 4 oz (113 g) of 0-46-0 per
planting hole is recommended.
Preplant applications of complete fertilizers are usually
not necessary when planting papaya, because the
developing seedlings can initially use nutrients stored
in the seeds. Soluble fertilizers placed in the planting
hole may burn the roots and make them susceptible to root
rots. Slow-release fertilizers generally do not burn
roots when mixed with the soil, and in commercial
practice they are applied on the soil surface when the
seeds are planted.
Postplant fertilizer applications. Moderate applications
of slow-release fertilizers are recommended during the
first few months of growth. Commercial growers apply 0.5
oz (14 g) of slow release fertilizer per hole at planting
and again six weeks later. Postplant fertilizer
applications usually begin three months after planting
with rates increasing with plant size. Maximum rates are
applied at five- to eight-week intervals after the plants
begin to flower. A typical application schedule with a
fertilizer such as 14-14-14 begins with 4 oz (113 g) per
plant per month during the third through fifth months
after planting. This rate increases to 6 oz (170 g) every
five weeks after the sixth month.
During winter months, when growth and fruit production
are slower, quantities of fertilizer applied should be
reduced. In the absence of rain or irrigation, repeated
fertilizer applications can lead to buildup of
undissolved fertilizers, which may release high
concentrations of nutrients into the root zone with the
next rainfall. Excessive N will cause excessive
vegetative growth and is also believed to contribute to
soft-fruit problems.
Papayas planted in replant fields often succumb to
diseases caused by accumulation of soil-borne pathogens.
A fallow period of three to five years may help to avoid
the replant problem. Preplant soil fumigation is an
alternative to the fallow period. On lava soils, the
"virgin soil" technique can be used. Soil is
collected from land where papayas have never been grown,
and approximately 0.5 cubic feet (14.16 cubic dm) of soil
is placed in holes that are at least 1 ft (30.5 cm) in
diameter and 4 to 6 in (10.2 to 15.2 cm) deep.
For best growth of young plants and good yields of
bearing plants, papayas should be irrigated as necessary
to supplement rainfall. When rainfall is limited,
commercial growers may apply up to 10 gal (37.851) of
water per tree per day to bearing trees. Yields can also
be increased by good weed control practices.
FERTILIZATION
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See Cultural Practices.
HARVEST and
POSTHARVEST Back To: Menu Bar
Papaya fruit should be harvested after color break - when
some yellow shows on the fruit - but before fully yellow
(about 9 to 14 months after planting). Fruit for home
consumption is best harvested when half yellow. If left
to ripen on the tree, the fruit is often damaged by fruit
flies and birds.
When papaya plants are short, fruits can be harvested by
hand while one is standing on the ground. As the plants
grow taller, harvesting aids are required. One technique
uses a modified plumbers helper to snap the papaya
from the stem. The fruit is caught before it falls to the
ground. One person can harvest about 800 to 1000 pounds
per day with this technique. Another technique involves a
platform rigged to a tractor, which lifts the workers.
This method requires flat terrain.
To be certified for shipment, fruit for export must be
harvested and packed in strict compliance with quarantine
regulations.
Harvested fruit is ripened at room temperature and
refrigerated when fully ripe. When ready to eat, fruit is
usually partially to fully yellow and slightly soft;
refrigeration can extend its storage life for several
days. In commercial situations, the storage life of
partially ripe fruit can be extended for up to two weeks
by holding it at about 50 F (10 C), but lower
temperatures may interrupt the ripening processes and
cause injury; the optimal storage temperature for fully
ripe fruit is about 36 F (2.2 C).
Papayas must be treated to kill any eggs or larvae of
fruit flies that may be present in the fruit. Treatments
include double-dip hot water treatments and vapor heat
treatments. The double-dip treatment may lose
certification for papayas destined for the U.S. mainland.
A dry heat treatment has been approved and awaits
certification.
DISEASES Back To: Menu Bar
Anthracnose and chocolate spot, Colletotrichum
gloeosporioides (fruits, petioles)
Phytophthora, Phytophthora palmivora (fruit, stem, roots)
Powdery mildew, Oidium caricae (leaves)
Black spot, Cercospora papayae (fruit)
Damping off, Pythium, Phytophthora, Rhizoctonia
(seedlings)
Wet rot, Phomopsis sp. (fruit)
Dry rot, Mycosphaerella sp. (fruit)
Watery fruit rot, Rhizopus stolonifer
Stem-end rot, Botryodiplodia theobromae, Mycosphaerella
sp., Rhizopus stolonifer, Phomopsis sp. (mature fruit)
Papaya ring spot virus (formerly referred to as papaya
mosaic)
Reniform nematodes, Rotylenchulus reniformis
Root-knot nematodes, Meloidogyne spp.
INSECTS Back To: Menu Bar
Stevens leafhopper, Empoasca stevensi
Mediterranean fruit fly, Ceratitis capitata
Melon fly, Bactrocera cucurbitae
Oriental fruit fly, B. dorsalis
MITES
Broad mite, Polyphagotarsonemus latus (seedlings, young
plants, lower surface of young leaves)
Red and black flat mite, Brevipalpus phoenicis (fruit)
Tuckerellid mites, Tuckerella ornata, T. pavoniformis
(trunks of old plants)
Carmine spider mite, Tetranychus cinnabarinus (lower
surface of mature leaves)
Citrus red mite, Panonychus citri (upper surface of
mature leaves)
Texas citrus mite, Eutetranychus banksi (upper surface of
mature leaves)
PRODUCTION Back To: Menu Bar
Papaya trees bear fruit throughout the year.
"Skips" in the fruit column caused by temporary
sterility may occur during hot, dry summer periods and
may cause fruit shortages in winter.
The plants will continue to bear for many years, but
yields usually decline as the trees age, and picking
becomes difficult. In commercial production, fields are
usually replanted or abandoned after three years.
Papayas marketed in or exported from Hawaii are regulated
by a Federal Marketing Order that sets fruit size and
quality requirements.
In the United States, Hawaii is the major producer and
supplier of papaya, with 2500 acres in 1989. It is also
estimated that there were 350 acres of papaya grown in
Dade County, Florida in 1987-1988.
The United States also imports papaya from foreign
countries. In 1989, the United States imported 6 million
lb of fresh papaya at a CIF (cost, insurance, and
freight) value of $1.1 million. Mexico was by far the
largest supplier, with 76% of the total. Other major
suppliers were the Bahamas (9.7%) and the Dominican
Republic (7.5%).
Production of papaya (fresh and processed) in Hawaii in
1989 was almost three times that in 1972. Storms affected
the production in 1979 and 1985. Poor weather, disease,
and Hurricane Iwa contributed to the decline in
production in 1982.
Most of the commercial papaya production is in Puna on
the Big Island. In 1989, about 97.4% of the papaya was
produced on the Big Island, followed by Kauai (1.3%),
Oahu (1.1%), and Maui and Molokai (0.2%).
The 1989 market supply of fresh papaya for the state of
Hawaii was 18.8 million lb. The major market was Honolulu
(78.2%), followed by the Big Island (10.1%), Maui and
Molokai (8.5%), and Kauai (3.2%).
During 1989, 44.6 million lb, or 70% of Hawaii's
production of papaya for the fresh market, was exported
out of state. The primary overseas destinations were the
US mainland (26.6 million lb), Japan (14 million lb), and
Canada (4 million lb). The major markets on the US
mainland were Los Angeles (61.4%), San Francisco (10%),
and New York City (9.4%). The average wholesale prices
for Hawaii papaya in these markets were $0.975/lb,
$1.15/lb, and $1.18./lb, respectively.
In 1992, the total farm gate value of papaya in Hawaii
was $14.4 million for the 71,300,000 lb harvested from
259 farms. A total of 55,800,000 pounds of the harvested
papaya was consumed as fresh fruit, while 15,500,000
pounds was processed. The average farm gate price of
papaya for the fresh market was 25.0 cents per pound. The
average farm gate price for processed papaya was
considerable lower at 3.0 cents per pound. The total
value of utilized production was $14,415,000.
Currently, papaya ringspot virus is a serious problem for
growers on Oahu and the Big Island. There is no cure for
the disease at this time and the only method of control
is prevention. This disease may affect papaya production
in the State of Hawaii detrimentally.
REFERENCES Back To: Menu Bar
Chia, C. L., M. S. Nishina, and D. O. Evans. 1989.
Papaya. Commodity Fact Sheet PA-3(A) Fruit. Hawaii
Cooperative Extension Service, CTAHR, University of
Hawaii.
Neal, Marie C. In Gardens of Hawaii. Hawaii: Bishop
Museum Press, 1965.
Tipton, Trace V., Kevin M. Yokoyama, Kulavit Wanitprapha,
Stuart T. Nakamoto and C. L. Chia. 1990. Papaya Economic
Fact Sheet #10. Department of Agricultural and Resource
Economics, CTAHR, University of Hawaii.
Statistics of Hawaiian Agriculture 1991. Prepared by:
Hawaii Agricultural Statistics Service, PO. Box 22159,
Honolulu, Hawaii, 96823-2159. December 1992. 105 pages.
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