Introduction to papaya flower and fruit drop, causes, control methods: Papaya (Carica Papaya L.) has become a popular fruit due to its fast growth, high yield, long fruiting period and high nutrient value as well. Papaya can be a highly profitable crop now. Papaya is a common man’s fruit is also known as a melon tree, papaw or papita. Papaya is an excellent source of vitamin ‘A’ and has a good amount of vitamin ‘C’, minerals (Fe, Ca and P) and carbohydrates. In this article we also discuss below topics;
- Why Papaya flowers falling off
- How do Papayas reduce fruit drop
- Control of flower drop in Papaya plant
- Papaya seed germination
- Pests and diseases affected by Papaya trees
- Papaya propagation
- Control of fruit drop in a Papaya tree
- Flower drop causes in a Papaya tree
- Effective control method of Papaya fruit and flower drop
A step by step guide to Papaya flower and fruit drop
If you are planning for commercial papaya farming, you must be aware of causes of papaya fruit and flower drop. Papaya flower has high nutritional value. The Papaya flowers have been used to control several ailments by our forefathers. After the consumption of Papaya flowers, a significant change has been seen in the levels of insulin in diabetic patients. Papaya flowers can stabilize high blood pressure; prevent heart diseases and many other ailments. After the consumption of the Papaya flowers, patients noticed a remarkable improvement in themselves. These flowers have Vitamin A, C, E and folate with anti-oxidant properties that prevent cholesterol and oxidation.
In case if you miss this: Management of Plant Viral Diseases and Control Methods.
Conditions for Papaya cultivation
Papaya is a tropical and very sensitive to frost. Optimum temperature is 25 to 30°C and a minimum of 16° C. The suitable pH level is between 6 and 6.5. The well-drained soil or sandy loam soil with adequate organic matter is most important for the Papaya cultivation. In high rainfall area, if drainage is poor and roots are continuously drenched for 24 to 48 hours, it causes the death of the plants. Sticky and calcareous soils are not good as rainwater could accumulate in the soil even only for a few hours.
- Propagation – Papaya fruit is commercially propagated through seeds. Seeds used for raising seedlings must be fresh as their viability is lost in about 45 days. The seed must be rubbed with wood ash to remove the mucilaginous coating to facilitate good germination. Papaya seed germination can take 3 to 5 weeks. Then the seeds want to be dried and dusted with fungicide to avoid damping-off, a common disease of seedlings. Seeds soaking for 24 hrs in distilled water after removal from storage will improve the seed germination rate. The seeds must be sown in the second week of January to February to escape the frost damage at the time of fruiting. Generally, 400g seed or 250 g hybrid seeds are sufficient to raise the seedling for one hectare.
- Seed germination – The optimum temperature range is 21 – 27° C, and of radical emergence is 19 – 29 °C and it takes 1 to 4 weeks from sowing to emerge depending on the temperature. The seed can be treated with Thiram (TMTD) W.P. before sowing to control the fungus diseases at the young plant stage.
- Sowing method – It can be sown directly, but normally, it is better to be seeded to raise seedlings and then transplanted.
- Spacing between plants – A 40 to 60 cm high bed is required if the soil is not well-drained. Normally, the distance between rows is about 2 to 2.5 m, and 2 m between plants (or 3m x 3m when grown at sloping land, or 2.7 m of the distance between beds for the tractor practice). The total number of Papaya plants for each hectare is about 2,000 to 2, 5000. In the case of eradication of virus-infected plants later, the distance between plants at the beginning of planting maybe 1.2-1.5 m.
- Manure and Fertilizer – Papaya plant is a heavy feeder and responds well to fertilizers. Application of 200g each of N, P and K per plant in addition to 25 kg FYM in split doses during the first, third, fifth and seventh month after planting resulted in higher Papaya fruit yield.
- Irrigation – Adequate watering is necessary, to ward off drought and frost, weekly in summer and biweekly in the winter season. The summer irrigation in Papaya is followed by earthing up. Waterlogging, in any case, should not be allowed the Papaya plants must not come in contact with water by placing 20 to 30 cm of the earth all round of young plants.
- Environmental temperature and Relative Humidity factors are usually out of the grower’s control. Light exposure of the trees is beyond practically supplying. To protect the Papaya plants from high winds the physical wind barriers can be made all along the borders without affecting the required air to pass. The controllable things possible practically, the disease and pest management can be monitored for avoiding the flower drop and get maximum yield. Proper balanced nutrient management may help to get good flower health and better fruit setting in Papaya crop.
- Papaya harvesting occurs at different times depending on the purpose of the harvest, but in general starts after ‘color break,’ which is the time when the fruit starts to turn from green to yellow color at the blossom end. Although ripe Papayas of different plant varieties range in color from yellow to orange or red, all are green before ripening and are referred to as green Papayas. For export purposes, Papayas are harvested from color break to one-fourth yellow. For local markets, harvesting is normally done when the fruit is one-half to three-fourths yellow. Fruits picked one-fourth to full yellow are sweeter than those picked green to one-fourth yellow because Papayas do not increase in sweetness after picking.
Papaya diseases and their control
The disease causes severe damage to plant leaves. The disease first appears as small, discolored lesions, which are irregularly scattered on the plant leaves. These spots become irregular in shape, and then increase in size, and appear brown to grey. And a light yellow zone surrounds the spots. Several lesions coalesce to cover large areas of the plant leaf and in severe infections, the whole leaf dies. A considerable reduction in the fruit yield is observed.
Control – Leaf – blight disease can be controlled by spraying of Dithane M-45 (0.2%) starting from the appearance of the disease symptoms.
Damping-Off is a disease of young seedlings. Lesions are seen on the plant stem at or just above soil level. The stem becomes watery and shrinks, followed by the death of the Papaya plant.
Control – Well-drained soil must be used for planting and the crop should not be excessively irrigated. Before sowing the seeds must be treated with the fungal culture of Trichoderma viride (3-4 g/kg of seed) or Captan (3 g/kg of seed) to protect the newly emerging seedlings.
The disease attacks the plants of all age groups but is most serious in young plants. The aphids are responsible for transmitting the Papaya Mosaic disease. The disease symptoms appear on the top young leaves of the Papaya plants. The infected plants show a marked reduction in plant growth.
Control – Good field sanitation such as removal and destruction of affected Papaya plants reduce the spread of the disease. Losses can be minimized controlling the population of aphid.
Leaf Curl of Papaya
Leaf curl disease is transmitted by the vector whitefly. Severe curling, crinkling and deformation of the plant leaf characterize the disease. Mostly the young plant leaves are affected. The affected plants show a stunted growth with reducing Papaya fruit yield.
Control – Removal, and destruction of the affected plants is the control measure to reduce the spread of the disease. Checking the population of whiteflies can reduce infection severity.
Reasons for Papaya fruit and flower drop causes and controlling procedure
Possible causes and control of flower drop in Papaya plant
Temperature and relative humidity [RH] – The environmental temperature and RH particularly microclimate near and around flowers must be in the range of 20°C to 33°C and 70 % to 85 % respectively. Lesser and higher than the range affects the pollination, fertilization of Papaya fruits and flowers drop off with forming to the fruit. Chemical growth regulators can sometimes help overcome low-temperature effect but the fruit developed will be seedless or could be of poor quality.
You should not miss Medicinal Plants Contract Farming and Advantages.
Lack or excess of nitrogen [N] fertility – Low and high dose of nitrogen can cause flower drop. The toxicity can be the direct effect of flower abortion. Ammoniacal nitrogen at even medium level has got an indirect effect on flower and fruit set. Indirectly ammoniacal nitrogen triggers regular viral infections which also result in Papaya flower dropping. Manganese micro-nutrient spray on high nitrogen doses may manage viral infections on plants.
Lack of water and excessive moisture can affect flower development, pollination, fertilization, and fruit set. Uneven water supply to the Papaya plants or trees induces stress leading to uneven flowering and fruit set.
Reduced or extended light exposure has an adverse effect and may affect Papaya flower development, pollination, fertilization, and fruit set.
Excessive wind naturally causes physical damage and pollens to swipe off leading to poor pollination and fertilization in plants.
Insect damage, particularly by the flower feeders, fruit feeders and probably by chewing type insects, will affect the Papaya flower health.
Causes and control of Papaya fruit drop
Early fruit drop in Papaya has several causes. These are the common reasons for fruit drop on Papaya trees;
Natural fruit drop in Papaya – If Papaya fruit is falling off when it is small, about the size of golf balls, the Papaya fruit drop is probably natural. A female Papaya plant drops fruit from flowers that were not pollinated. It is a natural process, while an unpollinated flower fails to develop into a fruit.
Naturally, the unfertilized flower drops the fruit in a Papaya tree. It occurs when fruits are small (i.e., about the size of a golf ball). The Papaya tree naturally drops fruit from flowers that were not pollinated. You’ll know this has occurred if the Papaya fruit is small, about the size of a golf ball.
Water issues – Some of the causes of Papaya fruit drop mainly involve cultural care. Papaya plants like water but not too much. Give these tropical plants too little and water stress can cause fruit drop in Papaya. If trees get too much water, you’ll see your Papaya dropping fruit as well. If the growing area is flooded, that explains why Papaya fruit is falling off. Keep the soil constantly moist but not wet.
Excess or too little water causes fruit drop in the Papaya plant. A fine line exists between irrigating a tree too much and too little. The Papaya tree doesn’t tolerate flooding or drought and will drop its fruit when the water supply fluctuates between extremes. It is susceptible to root rot in the winter if it’s given too much water.
Insufficient water – The tree needs an adequate supply of moisture in the soil to keep it growing vigorously all the time. If the amount of rainfall or water is given in irrigations is insufficient, the tree can cease flowering altogether. All but the uppermost leaves fall, and the trunk grows thinner and thinner at the top. In the time it can lose all its leaves and stop growing entirely.
With inadequate soil moisture, the tree cannot absorb enough water and the mineral nutrients dissolved in it, for good plant growth. With prolonged dryness, much of the root system can die, carrying the rest of the tree with it. The preventive is to keep the Papaya tree amply supplied with water at all times. The symptoms which characterize insufficient water quantity are similar to those from other causes that affect the root system adversely.
Pests – If Papaya fruit gets attacked by Papaya fruit fly larva, they will likely yellow and fall to the ground. The adult fruit flies look like wasps, but the larva is worm-like maggots that hatch from eggs injected into small green fruit. The hatched larva eats the inside of the fruit. As they mature, and they eat their way out of the Papaya fruit, which falls to the ground. You can avoid this problem by tying a paper bag around each Papaya fruit.
Fruit fly damage – Fruit flies larvae infect the Papaya tree. The infected Papaya fruits turn yellow and drop prematurely. Fruit infected with Papaya fruit fly larva will turn yellow and drop from the Papaya tree prematurely. Small and wasp-like, the Papaya fruit fly is yellow with black color markings. The larva resembles other typical fly maggots and the female fruit fly injects 10 or more eggs into small green fruit. When hatched, the larvae munch on the Papaya seeds and interior fruit pulp. Near maturity, and they eat their way out, drop to the ground and pupate in the soil. The best method to avoid fruit fly damage is to wrap a paper bag around the Papaya fruit and tie a string around the opening to secure it to the branch.
Phytophthora blight – The infected Papaya fruits shrivel up before dropping to the ground. If the Papaya shrivels up before falling to the ground, suspect a type of blight, and caused by species in the Phytophthora genus. Symptoms appear quickly as the Papaya tree turns brown and wilts. The entire tree can collapse in just a few days. Water-soaked lesions on the Papaya fruit, followed by white fungal growth indicate this disease. It can be controlled with the application of copper hydroxide-mancozeb fungicide spray when the fruit set begins.
Suspect Phytophthora blight if your fruit shrivels before it falls to the ground. The fruit will have water-soaked lesions and fungal growth but more than the fruit will be affected. The Papaya tree foliage brown and wilts, sometimes resulting in the collapse of the tree. Prevent this kind of problem by applying copper hydroxide-mancozeb fungicide spray at the fruit set.
Some questions about Papaya cultivation
You may also like the Stevia Farming in Polyhouse, Cultivation Practices.
Why did some Papaya plants fail to fruit?
Papaya trees in home gardens sometimes fail to fruit. This is not because the Papaya plant is unhealthy or undergrowth stress. It is a natural abortion of a female flower that had not been pollinated and then failed to develop into a fruit.
How do you keep a Papaya tree small?
To shorten a Papaya tree simply cut the top inch off of your Papaya tree. You should do this every time your tree grows about 5 inches. In young seedlings, this will affect a thicker trunk and older trees; it will result in more branches growing out the side rather than upwards growth.
What is the best fertilizer for Papaya?
Regular fertilizer applications with a balanced, all-purpose fertilizer help support proper Papaya growth and fruit development. For the best results, use a 14-14-14 product starting in the third month after planting Papaya. Use 4 ounces of 14-14-14 per Papaya tree, once every 4 weeks.
Why does Papaya leaves turning yellow?
Papaya lethal yellowing is a disease mainly caused by Papaya lethal yellowing virus (PLYV). The symptoms are characterized by progressive leaf yellowing and greenish circular spots on the Papaya fruits.
How long does a Papaya tree live?
The plant won’t survive frost and affected by shade, drought, and wind. Both indoor container Papayas and that grown outside generally are replaced after 4 to 5 years. Some Papaya trees can live longer than that if not uprooted, but fruit production and ornamental value decline after about four years.
Conclusion of Papaya fruit and flower drop
Well, proper control of Papaya fruit and flower drop will result in best fruit yield and quality produce. You may also check the Growing Dwarf Papaya from Seeds.