Cultivation of Papaya ;Carica papaya L.
Papaya is a very fast growing fruit crop and is grown in tropical and sub-tropical regions of the country. It is ranked the fifth most important fruit crop of the Nation. It is popular because its cultivation is easy, gives quick returns and adapts itself to diverse soil and climatic conditions.
Benefits of Papaya Fruit ;
Besides, the ripe fruit is very refreshing, high in nutritive values and is prized for its medicinal properties. Papain a protein digestible enzyme is found in white latex mainly from the immature fruits. It is said to be beneficial for the treatment of ulcer, diphtheria and even cancer besides being used for clarification of beer, tanning industry and manufacture of chewing gum.
papaya fruit is a good source of folate, Vitamin A, vitamin B, vitamin C magnesium, copper, pantothenic acid and fibre. One medium-size papaya has an approximately 120 gms. of calories, 30 gms of carbohydrate and 2 gms of proteins.
It is believed to be grown in about 97,000 hectares land with an average production of 5,520.63 1000 MT in various states in India like Bihar, Assam, Gujarat, Maharashtra, Tamil Nadu, Andhra Pradesh, Rajasthan, U.P., Karnataka, Chhattisgarh and Orissa.
Agro- Climatic Conditions Requirements for Papaya Cultivation ;
It can grow under dry conditions and can tolerate fairly extremes of temperature except for frost. However, it grows and fruits well in summer temperatures ranging from 37 to 43°C and winter temperatures of not below 12 – 14°C. The occurrence of too low temperatures and frost are limiting factors of its cultivation in north India.
Even though the tree is adapted to a wide range of soils, it grows best in the loamy soils. It does not tolerate water standing around the trunks nor will its roots live in water-logged soils. Soils with a pH range of 5.5 to 7 are very suitable for papaya cultivation. under the high humid and low-temperature condition fruit of papaya losses its sweetness. A warm and dry condition are required for ripening of Papaya fruit
Selection of Papaya varieties ;
Due to uncontrolled pollination and sexual multiplication, the varieties do not remain pure and give rise to variations both in tree and fruit characteristics. Some of the commercially grown varieties are –
State
|
Varieties
|
Andhra Pradesh
|
Honey Dew, Coorg Honey Dew, Washington, Solo, Co-1,Co-2, Co-3, Sunrise Solo, Taiwan , Arka Surya , Arka Prabhanath
|
Jharkhand & Bihar
|
Ranchi selection, Honey Dew, Pusa Delicious, Pusa Nanha, Pusa Majesty, Pusa Gaint
|
Karnataka & Kerala
|
Coorg Honey Dew, Coorg Green, Pusa Delicious, Pusa Nanha, Sunrise Solo , CO -3 , CO-4 , Arka Surya
|
West Bengal
|
Ranchi selection, Honey Dew, Washington, Coorg Green
|
Orissa & CG
|
Pusa Delicious, Pusa Nanha, Ranchi selection, Honey Dew, Washington, Coorg Green
|
Papaya Propagation;
The papaya plant is normally unisexual. The plant bears male, female and hermaphrodite (with male and female flowers on the same tree) and some other complex forms separately. Male flowers hang in long peduncles and are much smaller than female. The rudimentary pistils function in rare cases, leading to the development of small fruits which are of very little value. Thus, male trees are sometimes seen bearing small fruits.
Diseases of Papaya;
Foot Rot of Papaya (Pythium aphanidermatum ) ;
Footrot of papaya can be observed as water-soaked patches on the stem near the Ground Surface. These patches grow very rapidly and subsequently girdle the stem which causes the rotting of the tissues. Such type of affected plants can withstand strong wind and topple over and die. Under the mild attack of this disease, only one side of the stem rots and the plants remain stunted. Though fruit is not formed even if formed they are shrivelled and malformed in shape and size. Gradually the papaya plant dies under the influence of this disease.
Control; Apply Trichoderma viridi 15 gm /plant around the root zone, circular irrigation should be given, drenched the soil with copper oxychloride @ 2-3 gm /lit of water at the 15 days interval
Anthracnose of Papaya Plant:Colletotrichum gloeosporioides ;
Papaya anthracnose disease commonly appears on green immature fruits.symptoms of this disease are apparent in the form of brown to black depressed spots on the fruits. The basic symptoms are water-soaked, Brown sunken spots on the fruit surface of the papaya plant. which later on enlarge to form a water-soaked lesion on the fruit surface.
Control: Apply Spray of Copper Oxychloride (3 g/litre of water) /Carbendazim (1 g/litre of water) / Thiophanate Methyl (1 g/litre of water) at 15 days interval effectively controls the disease. Fruits for exports should be subjected to hot water treatment or fungicidal wax treatment.
Powdery Mildew (Odium Indicum, Odium caricae) :
High humidity (80-85%) and a temperature range of 24-26°C are the favourable condition for Powdery mildew in Papaya plant. its symptoms can be visualized on the foliage and pods in the form of white spots which later on enlarge and cover the entire leaf area. The Severely infected leaves may become chlorotic and distorted before falling. the size of the affected fruit became small and malformed.
Control: As the disease symptoms visualized the dusting Sulphur @30 g/10 litres of water / spraying Calixin 75 EC @5 ml/10 litres of water at 15 days interval helps to control the disease.
Leaf- Blight (Corynespora cassiicola):
This is a severe disease of papaya leaves. it first appears as small, discoloured lesions, which are irregularly scattered on the leaves.later on These spots become irregular in shape and increase in size, and appear brown to grey in colour. A light yellow zone surrounds the spots. Many lesions coalesce to cover large areas of the Papya leaf and in severe infections, the whole leaf of papaya plant dies. it causes a considerable reduction in the papaya yield.
Control; a spray of Dithane M-45 (0.2%) as soon the symptoms appears
Papaya Mosaic:
papaya mosaic may occur in all age groups but it is more serious on young plants. This disease is transmitted by the Aphids. Symptoms appear on the top younger leaves of the papaya plants. The size of leaves reduced and show blister-like patches of dark-green tissue, with an alternating the yellowish-green lamina. The fruits are borne due to this disease plants develop a water-soaked lesion with a solid spot in the centre. The shape of such fruits is becoming elongated and reduced in size.
Control: Removal and destruction of affected plant reduce the chance of disease spread. By controlling the population of aphid the losses in yield may be recovered. Spraying of Carbofuran (1 kg a.i./ha) at the time of seeds sowing 2-3 foliar sprays of Phosphamidon (0.05%) at an interval of 10 days starting from 15-20 days after sowing can effectively check the population of aphids.
Papaya Ring Spot Virus:
This viral disease is spread from plant to plant by aphids. The early visible symptoms on papaya are yellowing and vein-clearing of the young leaves. Subsequently, a very conspicuous yellow mottling of the leaves occurs and sometimes severe blistering and leaf distortion can also occur. Dark-greeny streaks and rings can also be seen in the leafstalks and stems of the papaya plant. Vigour of trees and fruit set is usually stunted depending on the age of the plant when infected. The quality of the fruit
( flavour ) is also adversely affected.
Control: Early detection and prompt removal of infected plants can stop the spread of the disease. Spraying of Carbofuran (1 kg a.i./ha) in the nursery bed at the time of sowing of the papaya seeds and 2-3 foliar sprays of Phosphamidon (0.05%) at an interval of 10 days starting from 15-20 days after sowing can control the Aphid populations
Pest of Papaya Plants;
Papaya mealybug (Paracoccus marginatus) ;
Mealybugs have a wide host range which often tended by ants which farm them for their sugary honeydew secretions. Flattened oval to round disc-like insect covered in cottony substances found the on papaya plant which causes chlorosis, stunted plant growth and leaf deformation, Due to the early leaf and fruit drop insects attract ants Due to which insect colony is formed which may also be associated with the growth of sooty mold due to fungal colonisation of sugary honeydew excreted by the insect.
Control; Mealybugs can be controlled by their natural enemies such as lady beetles but most commonly controlled using chemicals.
Spraying of neem oil (1 to 2%) or Fish Oil Rosin Soap (25g/litre of water) or by the use of chemical like profenophos 50 EC, chlorpyriphos 20 EC, buprofezin 25 EC, thiomethoxam 25 WG and imidacloprid 17.8 SL.
Scale insects (White peach scale);
Mating of adult scale insects retains their eggs inside the body until they hatch.
Scale insects damaged by continuous feeding the branches and fruit and injecting toxins into the plant.
Under the heavy infestation , gumming may occur on the bark and twigs or entire branches can be damaged; insects are flattened discs, or “scales” with no visible legs; scales insects produce a white waxy coating which later on turns in black.
Control; Papaya plant can be sprayed with certain horticultural oils which effectively kill scales without affecting the natural enemies.