Unit – 10
Cultivation Practices of Papaya
PAPAYA (Carica papaya)
Introduction
Papaya (Carica papaya L.) is an important fruit crop throughout the tropical and sub-
tropical countries. It is an almost herbaceous (succulently soft-wooded), typically
unbranched small tree in the family caricaceae. Papaya is one of the most important tropical and sub-tropical short gestation fruit crops and cultivated from the terai to mid hills of Nepal.
Composition and uses
It is rich source of vitamin A and minerals. Ripe papaya is eaten fresh as breakfast and
dessert fruit. It is made into fruit salad or juice and can be processed as jelly,
marmalade, candies and crystallized fruits. Green fruits are pickled or cooked as
vegetable.
Origin and distribution
It’s origin is considered to be lowlands of central America and southern Mexico,
possibly West Indies (Caribbean). It is found throughout the tropical and subtropical
world; in protected culture in cool subtropical regions.
Variety
1. Pusa delicious
This is good variety to fruit yield and quality. It is gynodioceous variety with cent
percent productive plants having excellent fruit taste coupled with good flavour and
orange flesh colour.
2. Pusa majesty
This is variety with high productivity and better keeping quality of ripe fruit. This is
also gynodioceous variety with rich source of papain. This variety is also resistant to
papaya nematode.
3.Pusa giant
This is a vigorous dioecious variety with good size of fruits. The plants are sturdy and
tolerant to strong winds and storms and fruit is most suitable for tutti- fruity and petha.
4. Pusa dwarf
This variety is chiefly characterised by dwarf stature of plane with good fruit yield.
Fruits are of medium size with oval shape which is preferred by consumers.
5. Pusa nanha (mutant dwarf)
This is extremely dioecious mutant dwarf variety suitable for kitchen gardening, pot
and roof cultivation. This variety is ideal for high density orcharding.
6. Washington
The plants are vigorous, stem and leaf stalks are with purple tinge, fruits are medium
to large, round to ovate, sweet, pulp orange colour with good flavour.
Climate and soil
It is tropical fruit. It can be grown commercially at the altitude of 1000 masl. The optimum temperature required for is proper growth and development lies between 200°c-270°c. The annual rainfall required for its cultivation is 1000- 2000 mm. A well drained sandy loam soil having high organic matter is suitable for its cultivation. The pH of the soil should be 6-7. Under water stagnated conditions and in soils with poor
drainage foot rot disease may cause heavy mortality. Hence, heavy soils should be
avoided as papayas cannot withstand water stagnation for more than 48 hours.
Area and production
Area (ha): 1457; productive area (ha): 1011; production (mt): 12912; productivity
(mt/ha): 13
Propagation and planting
It is propagated by seed. Seeds are sown in polybag or directly sown in a well prepared
nursery bed at 15cm x 20cm spacing. The seedling become ready for transplanting
when plant attain height of 15-20cm and have 4-5 leaves. The pit size of 1-1.5 cubic
feet should be dug at 1.8 x 1.8m or at 2.4 x 2.4m apart and filled with top soil mixedwith 5 kg of FYM, 100 grams of neem cake and 40 grams of super phosphate and
planting is done during monsoon season.
Irrigation
Irrigation is required at 5-6 days interval in summer and 10-15 days interval in winter
by adopting ring method.
Manure and fertilizer
The recommended dose of compost, nitrogen, phosphorus and potassium should be:
Compost: 25kg per plant per year
Nitrogen: Phosphorus: Potassium: 400:250:400 g/plant/year.
The fertilizer application is done in 2 splits; one in Shrawan/Bhadra and other split in
Falgun.
Training and pruning
Papaya trees do not need pruning because their main growing point is terminal. Select
one or two of the most vigorous side shoots and remove the others to facilitate growth
and fruiting of the remaining shoots. After fruiting, prune the plant to 12 inches from
the ground. When new shoots appear, select the strongest as the new leader and cut
back the others.
Intercropping
No intercrop should be taken when flowering and fruiting starts. Intercropping of leguminous crop after non leguminous one, shallow-rooted crops after non-
leguminous one and shallow-rooted crops after deep rooted ones are gainful.
Intercultural operations
Deep hoeing is recommended during the first year to check weed growth. Weeding
should be done on regular basis especially around the plants. Application of
fluchloralin or alachlorin or butachlorine (2.0 gm/ha.) is done. As pre-emergence
herbicide two months after transplanting can effectively control the weeds for a period of four months. Earthing up is done before or after the onset of monsoon to avoid water-logging and also to help the plants to stand erect.
Flowering and pollination
Papaya pollination is a bit of a mystery. Horticulturists believe it is usually carried out by insects or the wind, although they are not exactly sure how it works. In some cases,
hand pollination may be needed to ensure proper fruit set.
The gender of a papaya plant can be determined by its flower male, female, or bisexual.
To make sure you obtain at least a few fruit-bearing plants (females), plant several
clumps of seedlings, and then thin them down to a single female or bisexual plant after they start flowering (5 to 6 months of age). Female plants can be identified by their
flowers location (they appear along the trunk) and by the presence of a miniature
papaya fruit inside the base of the flower petals. Bisexual flowers look similar to
female flowers, but the miniature papayas inside the base of their petal is surrounding
by male stamen. If no bisexual plants are present, one male plant is needed for every
8 to 10 females.
Fruit growth and development
Fruit growth shows two major phases. The first phase of rapid growth lasts about 80
days after flower opening, while the second phase is apparent just before fruit maturity.
Flesh color is white in immature fruit to a pale orange-yellow, salmon pink, or red
depending upon cultivar in ripe fruit. Total fruit starch declines during the first 80 days
of fruit development. Sugars begin to accumulate only during the last 28 to 42 days of fruit development. Fruit development usually takes 130 to 160 days from anthesis in the tropics and can be extended to 190 to 270 days in the cooler subtropics.
Insect pest of papaya
1. Aphid (Aphis gossypii, A. citricola and A. crassivora)
Adult and nymph suck the sap from tender leaves and shoots.
The plant becomes unproductive when aphids attack.
It also transmits several viral diseases like Papaya Ringspot Virus (PRSV).
Control:
Adopt clean cultivation
Spray imidachloprid 0.006 % and mineral oil 1% alternately forthnight.
2. Scale insect (Aspidiotus spp. and Aonidiella orientalis)
Adult and nymph suck the sap from leaves and tender part.
Yellow discoloration is seen on the affected part.
Later on the infected part dry out and yield is reduced.
Control:
Adopt clean cultivation
Pruning affected plant parts is sufficient to check the spread of scales.
Spray delfin @ 2ml/lit of water
3. Mites (Tetranychus cinnabarinus and Brevipalpus phoenicis)
They make white spots on ripe fruits and also affect the leaves.
Control:
A spray of dicofol 0.05% on the underside of leaves during summer
brings about good control if the infestation is treated early.
Release of the predatory mite, Amblyseius spp. also mitigates the
problem.
Spray sulphur dust @ 0.6g/lit of water.
Disease of papaya
Collar rot ( stem rot)
Causal organism: fungus
S.n.: Pythium aphanidermatum
Symptoms:
Water soaked patches appear on the colar region of the plant.
Later on the patches appear in large size and cause rotting of tissue. The pant
fall and die in severe condition.
Control:
Avoid water logging condition in field
Uproot and destroy the affected plant
Application of Trichoderma viridae (15 g/plant) mixed in well-decomposed FYM should be applied around the root zone of the plants at the time of planting.
At the initial stage, scrap the infected part and apply Bordeaux paste.
Anthracnose
Causal organism: fungus
S.n :Colletotrichum gloeosporioides
Symptoms:
Small black spots appear on the leaves and fruits.
The spots increase in size, penetrating and rotting the internal flesh.
The affected leaves fall pre-maturely.
Control:
Collect and destroy infected leaves and fruits.
The fruits should be harvested as soon as they mature.
Spaying with Copper Oxychloride (3 g/litre of water) or Carbendazim (1 g/litre of water) at 15 days interval effectively controls the disease.
Leaf curl
Causal organism: Leaf Curl Virus
Vector: White fly (Bemisia tabaci)
Symptoms:
Curling and bending of leaves takes place which cause reduction in the leaves
size.
The leaf margin rolled downward and the affected leaves become zigzag.
Later on defoliation takes place.
Control:
Collect and destroy the infected part of the plant.
Removal and destruction of the affected plants is the only control measure to reduce the spread of the disease.
Checking the population of white flies also can reduce the infection
severity.
Powdery Mildew
Casual organism: (Oidium caricae and Laveillula taaurica)
Symptoms:
On the underside of diseased leaves are found patches of whitish powderymaterial, which
On the upper surface, leaves at the infection side show blotches of yellow or
pale green usually near the veins, surrounded by normally coloured tissue.
Early less conspicuous symptoms consist as pale yellow spots near the veins.
Control:
The systemic fungicides like Bavistin (0.1%) at monthly intervals are
much more effective.
Physiological disorder
Green, slightly sunken areas on ripe yellow fruit are caused by scratch injury when
fruit were still green. Unsightly skin freckles (small, brown, slightly raised areas) that
are more common on the side of the fruit exposed to the sun is seasonal, developing
when rainfall and low temperatures occur 2 months before harvest. Premature ripening
of fruit, referred to as “soft fruit,” is related to low calcium content. This condition is
more common following periods of heavy rainfall 2 to 3 months before harvest.
Sunken, dry, brownish-grey areas are caused by mites feeding on skin during early
fruit growth.
Stage of maturity
Fruits are harvested when they are of full size, light green in colour with tinge of yellow at apical end. On ripening, fruits of certain varieties turn yellow while some of them remain green. When the latex ceases to be milky and become watery, the fruits are
suitable for harvesting.
Harvesting methods
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 plumber’s helper to snap the papaya from the stem. The fruit is caught
before it falls to the ground.
Yield
A young tree yields about 70-120 fruits per plant up to 4 years. Later becomes
unproductive after 4 years
Grading
Fruits are graded on the basis of their weight, size and color.
Packaging
Bamboo baskets with banana leaves as lining material are used for carrying the
produce from farm to local market.
Transport
Rough handling of boxes/cartons during loading/unloading should be avoided. Over
loading should be avoided. To reduce bruising, good shock absorbers should be used.
Storage
Fruits are highly perishable in nature. They can be stored for a period of 1- 3 weeks at
a temperature of 10-130°C and 85-90% relative humidity.
THE END