Iqra Mumtaz, Dr. Rashid Mukhtar Balal, Mujahid Ali
(Horticulture, College of Agriculture, University of Sargodha)
Pakistan is honored with different environments for the development of a variety of fruits and vegetables. The southern parts of Pakistan are suitable for citrus, mango, banana and other tropical fruits like papaya while the north and north-western parts give appropriate conditions to temperate fruits like grapes, apple, apricot etc. Papaya mostly found in tropical and sub-tropical zones of the world however in Pakistan, the area of Sindh and Punjab is rich in lavish green plantations of papaya. Seaside territories of Sindh province and Malir zone of Karachi have been developing papaya on large scale. Papaya developed in Thatta and Malir Districts of Sindh are known for their sweetness and size. Papaya fruit has a lot of love. It is honored as ‘The Fruit of Angels’ by Christopher Columbus. It is considered minor fruit in Pakistan yet have a lot of potential in Pakistan, so we should focus on its cultivation. Its leading producing countries are India, Brazil, Indonesia, Nigeria, and Mexico.
Papaya botanically known as Carica papaya has a place with family Caricaceae has turned out to be prevalent natural product because of its long fruiting period, quick development, high nutritive esteem and high return. It was originated from tropical America and as of now developed in Hawaii, Sri-Lanka, Philippines, Indonesia, South America, India, and Pakistan as business level development. While the name papaya is widely recognized, it has been corrupted to kapaya, kepaya, lapaya or tapaya in southern Asia and the East Indies. In French, it is papaye (the fruit) and papayer (the plant). Spanish-speaking people employ the names melon zapote, papayo or papayero (the plant), depending on the country. In Brazil, the usual name is mamao. When first encountered by Europeans it was quite naturally nicknamed as “tree melon. According to 2018 top papaya producing countries are India, Brazil, Indonesia, Nigeria, Mexico, Philippines respectively. Papaya spread toward the south by Indians, and all through the Caribbean with Spanish exploration. The Spanish likewise conveyed it to Europe and the Pacific Islands. By the mid-seventeenth century, papaya was distributed pantropically. Papaya was acquainted with Hawaii in the 1800s, and Hawaii remains the main state in the USA to deliver papaya monetarily. A little industry created in Florida in the initial segment of the twentieth century yet declined quickly with the introduction of viral diseases. In fact, the current decay of the Hawaiian business was caused essentially by a similar pathogen that crushed plants in Florida papaya ringspot virus; however, the disease was overcome by biotechnologists at the University of Hawaii, who inserted a gene into the ‘Sunrise’ cultivar that conferred resistance to the virus. This made the papaya the principal hereditarily altered fruit crop utilized for the human. Since 1998, a large portion of the papaya real estate in Hawaii has been changed to hereditarily modified cultivars.
Papaya is delicate, the single-stemmed tree having a height of 1-3 meter. The plants are straight having an umbrella of leaves on the top. The upper surface of leaves is dark green and lower surface is light green. Both the stem and leaves contain overflowing white smooth latex. Regularly, the species is dioecious, male and female blooms being delivered on isolated plants; however androgynous structures are known and various inconsistencies in the dissemination of the genders are normal. Male blossoms are borne in bundles on stalks 90 cm long, the blooms are funnel-shaped, around 2.5 mm long, and whitish, and the corolla is five-lobed, with 10 stamens in the throat. The female blossoms are extensively bigger, on short stalks, and regularly singular in the leaf axils, they have five fleshy petals that are joined toward the base and a substantial round and hollow predominant ovary that is delegated by five fan-formed sessile stigmas.
By and large, the fruit is melon-like, oval to almost round, to some degree pyriform, 15-50 cm long and 10-20 cm thick; weighing up to 9 kg. The skin is waxy and thin. At the point when the natural product is green and hard, it is rich in white latex. As it matures, it turns out to be light-or profound yellow and the thick mass of succulent substance winds up sweet-smelling, yellow, orange or different shades of salmon or red. It is then delicious, sweetish and to some degree like a melon, in a few kinds very musky. Seeds are peppery around 3/5 mm long, each covered with a transparent, coagulated aril. The percentage composition of typical papaya seed is (8.5 %), skin (12 %) and pulp (79.5%). Papaya can be productive for only three years and fruit size become small after 3 years.
Papaya is a tropical, plant, sensitive to frost. Optimum summer temperature ranges from 38 – 40°C and least in winter should not be beneath 5°C. Reasonable pH esteem is about 6.5 to 7.5. The depleted or sandy topsoil with sufficient organic matter is essential for the papaya growth and development. In high precipitation territory, if seepage is poor and roots are persistently doused for 24 to 48 hours, it might cause the demise of the plants. Sticky and calcareous soils are bad as rainwater may aggregate in the dirt even just for a couple of hours. In this case, higher raised bed and drainage ditch are recommended. Papaya dislikes solid, cool, dry weather. It is better to grow in sheltered but full sunshine place. Staking or windbreak can diminish the harm to plants under strong wind.
Varieties of papaya include CO1, CO2, C03…CO7, Coorg honeydew, Pusa majesty, Pusa dwarf, Red lady, Washington, sunrise solo and pusa delicious. Papaya is usually propagated by seed. Cutting or grafting methods are not feasible due to the fragile nature of stem.
Papaya is planted during spring (February-March), monsoon (June-July) and autumn (October-November). 250-300g seeds are adequate for a hectare. Seeds can be sown directly, or seedlings can be raised in beds or pots and then are transplanted into actual filed at the suitable age. Well-prepared seeds can be stored for 3 years but the percentage of germination declines with age. Dipping for 15 seconds in hot water at 158º F and then soaking for 24 hours in the distilled water after removal from storage will improve the germination rate. If germination is slow, we can spray Gibberellic acid to boost up the germination rate. Generally, 15-20 cm tall seedlings become suitable for planting in around two months. The seedlings can be brought up in nursery beds 3m long, 1m wide and in pots or polythene bags. The seeds ought to be sown 1cm down in lines, 10 cm apart and covered with fine compost of leaf mold. After seed germination when plants attain the height of almost 15-20 cm they are transplanted into the actual field. One male plant should be planted for pollinating the 10 female plants. Slightly irrigation should be done in the morning. Ring irrigation method is preferable as it prevents contact with trunk and thus prevents collar rot disease of papaya. Seedling should be protected with the polyethylene sheet. Papaya starts blooming within 4-6 months after seeding while bearing within 10-12 months.
Papaya plant needs overwhelming measurements of composts and manures. Aside from the basal dose of manure (@ 10 kg/plant) applied in the pits, 250 each of Nitrogen, P2O5 and K2O are applied for getting the high yield of papaya. Application of 200 g Nitrogen is ideal for fruit yield however papain yield increases with increment in Nitrogen up to 300 g. Lack of lime and boron has frequently been seen in papaya plantations. Spraying of 0.5%zinc sulfates (twice) and the spray of Borax (0.1%) might be finished relying on the supplement status of the soil. Fertigation would be desirable in case the plants are drip irrigated.
Papaya takes 145-165 days from flowering to fruit ripening. Harvesting for the local market in winter months, papayas might be permitted to shading genuinely a long time before picking, yet for the nearby market in summer and for shipment, just the main sign of yellow is reasonable. The natural products must be taken with incredible care to abstain from scratching of latex which recolors the fruit skin. As papaya is highly perishable it needs careful post-harvest handling. For local market, it should be stored in a single layer of straw while for distinct markets it should be packed in bamboo baskets with rice straws. To reduce post-harvest fruit losses, it is treated with heat at 110-120° F and then rinse with cold water. Wax is also applied during packing. Radiation treatment is also given to sterilize fruit fly eggs and larva in fruit intended for export. Fruits can be treated at 85°F and 100% humidity for the export purpose to reduce fruit injury.
Essential and widespread insects of papaya are papaya webworm or fruit cluster worm, aphid, papaya fruit fly, red spindle mite, stem borer, grey weevil and root-knot nematode. For controlling the insect pest, the infected plant part needed to be destroyed along with the application of prophylactic sprays of Dimetoate (0.3%) or methyl demonton (0.05%).
The main diseases are powdery mildew, anthracnose, papaya leaf curl virus, stem rot and damping off. Application of wettable sulphur (1g/liter), thiophanate methyl (1g/liter), mancozeb (2g/liter) has found to be effective for controlling diseases of papaya.
Papaya is a nutraceutical plant having an extensive variety of pharmacological exercises. The various favorable circumstances of papaya are owed because of a high substance of vitamin A, B, and C, proteolytic proteins like papain and chymopapain which have antiviral, antifungal and antibacterial properties. Papain prepared from the dried latex of its immature fruits is used in meat tenderizing, manufacture of chewing gum, cosmetics, for degumming natural silk and to give shrink resistance to wool. The possible therapeutic points of interest of eating up papaya fuse a diminished threat of coronary ailment, diabetes, coronary illness, supporting in handling, improving blood glucose control in people with diabetes, cutting down circulatory strain, and upgrading wound patching. Papaya leaves also contain cancer-fighting substances. Papaya makes our immune system strong because it contains vitamin A and vitamin C and these both are needed for the healthy immune system. Papaya can be utilized as serving of mixed greens and in other combinations. Papaya can be devoured as watermelon. Papaya is widely used as a fresh fruit and for jellies, ice-cream, pies, and as dried and crystallized fruit. Papaya is used in cosmetic industry. Dried leaves have been smoked to relieve asthma. Dried leaves are also used for making tea. The inner bark has been used for toothache relief.
Finally, it can be concluded that papaya is nutritious, healthy as well as highly profitable fruit. But papaya cultivation is not commercialized to the extent it deserves. Thus, we should try to enhance area and productivity level of papaya as papaya is highly remunerative crop and gives high return per unit area than other fruit crops. We should advise our farmers to grow papaya on large scale to earn high amount of revenue.