Mango tree diseases pictures

Getting to the Root of Mango’s Problems

QUESTION: I have a 3-year-old mango plant, and since last year its leaves have been shriveling and turning brown. Is there a cure for this condition?

–F.V., Montebello

ANSWER: What you describe sounds like too little water, though if the leaves first turn yellow, it could be too much water. This is always a tough call, checkable only by actually probing near the roots to see if the plant is wet or dry.

Or give the tree a gentle tug and see how well rooted into the soil it is. The roots could still be in the root ball and not in your garden soil and be drying out too fast. I killed a new citrus this way, not realizing that the root ball was going dry even though the soil around it was moist.

Advertisement

If the tree pulls right out of the ground with virtually no root, then too-frequent watering has rotted them off.

If the leaves get crinkly and the tips and edges turn brown first, it could be a nutrient deficiency or salts in the soil or water. As are citrus and avocados, mangoes are sensitive to too much boron or too little manganese, zinc and iron.

Readers shouldn’t be surprised to hear that someone is growing mangoes in a backyard. In the warmer, nearly frost-free areas, they have been grown for years.

According to David Silber, proprietor of Papaya Tree Nursery in Granada Hills, mangoes will grow where a ‘Haas’ avocado will (where temperatures seldom go below 28 degrees) and, in time, attain the size of a Valencia orange. Fruit ripens in fall in Southern California when there are very few in markets, an added bonus.

Advertisement

Don’t plant a pit from a store-bought fruit. Grown from seed, plants take up to 10 years to produce; grafted kinds produce right away, though baby fruit should be stripped off the trees until their trunks are about an inch across, measured a foot above the ground. Silber says they’ll even grow for years, and produce, in a 15-gallon container.

He sells several kinds, but his favorite is what’s called a “California variety,” named ‘Thompson.’ ‘Reliable’ is another, and he’s had good luck with ‘Edward,’ a Florida variety.

All of these fruit heavily in the Southland. There are also Philippine and Indian types (mangoes are native to India). Trees are self-fruitful, so you’ll need only one. Picked ripe off your own tree, the fruit are delicious.

Sow Bugs Don’t Harm Living Plants

Q: Those cute little roly-poly sow bugs are destroying my garden. They are killing daisies and poppies and are even eating my strawberries. What can I do?

–L.O., Simi Valley

A: Sow bugs and pill bugs (pill bugs roll up into tight little balls, sow bugs don’t) shouldn’t be harming living plants. They primarily feed on rotting or decaying matter, though they will nibble on young seedlings. If they really are doing the damage in your garden, you have an epidemic-sized problem that is probably cultural.

An excellent University of California publication called “Pests of the Garden and Small Farm,” (No. 3332, 994-8849, $30) says that sow bugs and pill bugs “get blamed for more than they do,” because they are often found on fruit or flowers that were initially damaged by some other creature. Snails, for instance, may eat the plants at night, but by morning all you see are the sow bugs feeding on the already damaged and decaying sections.

Advertisement

First check to make sure other creatures are not doing the initial damage, then look at environmental factors such as irrigating too often or some kind of chunky mulch where they can hide and breed in excess. Sow bugs are soil-dwelling crustaceans, breathing through gills and related to crayfish, and they require moist conditions. A thick mulch that keeps the soil moist encourages breeding. Watering too often also keeps the ground too moist (and may actually cause some of the initial decomposition), encouraging their activity.

Don’t spray or use poison pellets. It most likely isn’t necessary, and these little creatures actually have an important role to fill in the garden–helping old vegetable matter break down. Cut back on watering, water early in the day, encourage good air circulation in the garden and consider using another kind of mulch. Figure out how to elevate fruits lying directly on the moist ground so they do not rot.

Strawberries are particularly susceptible; mulch with black plastic or clean hay and keep it on the dry side, or put berries in little raised beds so the berry clusters can hang over the side, off the ground, and dry out.

Mango
Other Names: Manako

GENERAL CROP INFORMATION

This summary was prepared from publications by
Chia, C. L. et. al. and Wanitprapha, K., et. al..

FAMILY: Anacardiaceae
SCIENTIFIC NAME: Mangifera indica L.
ORIGIN: South and Southeast Asia

DESCRIPTION Back To: Menu Bar
Mango trees are deep-rooted, symmetrical evergreens that attain heights of 90 feet and widths of 80 feet. Mango trees have simple alternate lanceolate leaves that are 12 to 16 inches in length and yellow-green, purple, or copper in color when young. Mature leaves are leathery, glossy, and deep green in color. New leaves arise in terminal growth flushes that occur several times a year. Mature terminal branches bear pyramidal flower panicles that have several hundred white flowers that are about a 1/4 inch wide when open. Most of the flowers function as males by providing pollen, but some are bisexual and set fruit. Pollination is by flies, wasps, and bees.
The fruit weighs about 1/4 pound to 3 pounds. Fruit may be round, ovate, or obovate depending on the variety. The immature fruit has green skin that gradually turns yellow, orange, purple, red, or combinations of these colors as the fruit matures. Mature fruit has a characteristic fragrance and a smooth, thin, tough skin. The flesh of ripe mangos is pale yellow to orange. The flesh is juicy, sweet, and sometimes fibrous. Some undesirable seedlings or varieties are described as possessing a turpentine-like off-taste. The fruit has one seed that is flattened and sticks to the flesh. The seed contains one or more embryos depending on the variety or type.
VARIETIES Back To: Menu Bar
‘Ah Ping’, ‘Fairchild’, ‘Gouveia’, ‘Harders’, ‘Keitt’, ‘Momi K’, ‘Pope’, and ‘Rapoza’ are recommended mango varieties for Hawaii. All the listed varieties are productive and have superior quality fruit. They have less pronounced alternate-year bearing qualities than the more common ‘Haden’ and ‘Pirie’ varieties. All these varieties, including ‘Haden’ and ‘Pirie’, are monoembryonic and do not come true from seed. Flowering occurs from December to April, but offseason flowering is common, resulting in variable harvest times. ‘Fairchild’ is considered somewhat resistant to anthracnose and is favored for humid areas.
‘Exel’ is a high quality mango cultivar developed by the Department of Horticulture, University of Hawaii. It was selected from an open-pollinated population of ‘Irwin’ seedlings. Young ‘Exel’ trees begin to bear three to four years after transplanting into the orchard. ‘Exel’ bears fruit regularly, sets well and frequently flowers during the off season. Fruits usually mature in July and August but in some years, may mature as late as October. ‘Exel’ trees should be planted in sunny, dry areas to prevent anthracnose damage to immature fruit and flowers.
‘Exel’ fruits are ovate, 4 to 5.6 inches in length by 2.8 to 3.6 inches in width, with a short, rounded beak. The average fruit weight ranges from 14.1 to 17.6 ounces. The penduncle is set at the top of the fruit. Immature fruits are green with a purple blush. Mature fruits are yellow with a red over color on about half of the surface of the fruit. The flesh is firm, orange-yellow, juicy, sweet, and fiberless. The fruit has 18% total soluble solids. More than 90% of the fruit is edible flesh, because the fruit has a thin, flat seed.
USES Back To: Menu Bar
Mango can be eaten raw as a dessert fruit or processed to various products. Ripe fruits can be sliced and canned or processed to juice, jams, jellies, nectars and preserves. Eastern and Asian cultures use unripe mangos for pickles, chutney and relishes. In India, unripe mangos are sliced, dried, and made into powder for amchoor, a traditional Indian preparation used for cooking.
In India, flour is made from mango seeds. Seeds are also eaten during periods of food shortages. The timber is used for boats, flooring, furniture and other applications.
Raw mango consists of about 81.7% water, 17% carbohydrate, 0.5% protein, 0.3% fat, and 0.5% ash. A 100 g (3.5 oz) serving of raw mango has 65 calories and about half the vitamin C found in oranges. Mango contains more vitamin A than most fruits.
PROPAGATION Back To: Menu Bar
Monoembryonic mango varieties, like the varieties recommended for Hawaii, have single embryos of hybrid origin and do not produce true from seed. They are propagated by grafting onto seedling rootstocks. Polyembryonic mango varieties, like the so-called common or Hawaiian mango varieties, produce two or more plants of nucellar (maternal) origin from each seed. These plants are predominantly true to type, and may be grown from seed without the necessity of grafting.
Grafted trees grow more slowly than seedling trees and are often smaller. Grafted trees usually produce fruit in 3 to 5 years in dry areas, while seedling trees usually take at least five years to come into bearing. Mango trees can remain in production for 40 years or more. Inarching is sometimes done to propagate mango varieties, and older trees may be topworked. Mangos are not propagated from cuttings or by air layering because the resulting trees are weak rooted.
SOIL TYPES and LOCATION Back To: Menu Bar
Mangos can be grown on a wide range of soil types, from light sandy loams to red clay soils. Soil pH of 5.5 to 7.5 is preferred. Deep rich soils give the best production and fruit quality. Well drained soils are recommended. Moderately sloping sites are also recommended to prevent waterlogging. Deep soils without impermeable layers permits the development of deep taproots that aids in drought tolerance and wind resistance.
Mangos will grow from sea level to an elevation of about 1,500 feet in Hawaii, but mangos are most productive below 1,200 feet. Mango is best adapted to hot, dry leeward areas that receive less than 60 inches of rainfall annually, but supplemental irrigation is desirable for highest yields in those areas. Anthracnose disease often destroys both flowers and developing fruits in humid, high-rainfall areas.
Dry weather during the flowering period is best for fruit production. Wind can damage flowers and reduce yields. Mango trees should be protected from strong winds, but windbreaks that shade or compete with them should be avoided.
CULTURAL PRACTICES Back To: Menu Bar
Transplant container-grown plants promptly, before they become pot-bound, to permit good root development. Avoid transplanting plants that are flushing. Treble superphosphate (0-45-0) fertilizer should be mixed with the soil in the planting hole, but other fertilizers should not be applied until after the plants recover from transplanting shock.
Mangos are large trees and should be planted 35 to 40 feet apart. For increased early production, an extra tree may be planted in the center of a 40-foot square to be removed later. Unfortunately, however, this extra tree is seldom removed, which leads to overcrowding. Developing trees should be trained to eliminate low branches less than 2 feet from the ground, leaving three to four main branches on the trunk at different heights. The few fruits set in a tree’s first years of fruiting should be removed to speed up tree development. Pruning of well-formed older trees is usually confined to removal of dead branches. Pruning is preferably done after fruiting, before a growth flush occurs. Pruning can also be done to restrict tree size for small yards or when more than 35 trees per acre are planted. Some delay in flowering can be expected from new growth produced in response to pruning.
Young mango trees should not lack water. If rainfall is limited, irrigation water should be applied about once every two weeks during the first year, every three weeks during the second year, and once a month thereafter. Mature trees are more productive if irrigation water is withheld for at least two months before flowering. Although hot, dry weather is favorable to fruit development, supplementary irrigation between flowering and harvest is advisable for good yields.
Fertilizer may be a 1:1:1 or 1:2:2 N-P-K ratio formulation, such as 16-16-16 or 10-20-20 N-P-K. During tree establishment, phosphorus (P) is important for root development. Nitrogen (N) and potassium (K) are needed by bearing trees for good yields. Young trees should receive 0.1 to 0.2 pound of N (e.g., 1 to 2 pounds of 10-20-20 fertilizer) per year during the first year and 0.15 to 0.3 pound of N (e.g., 1.5 to 3 pounds of 10-20-20) during years two and three. The total annual amount of fertilizer should be divided into three or four applications, preferably applied before growth flushes are anticipated.
In general, bearing mango trees should receive about 1 pound of a complete fertilizer (containing N, P, and K) annually for each inch of trunk diameter measured 4 to 5 feet above ground level. Half of the fertilizer should be applied just before flowering and the rest applied after the crop is harvested. Supplemental N should be applied just before flowering rather than during fall and winter, when vegetative growth flushes rather than flowering occur. Slow-release fertilizer formulations are preferred, except for supplemental N applications, which should have rapid release. Fertilizers should be spread in a zone directly beneath the leaf drip line and, if possible, application should be followed by irrigation.
FERTILIZATION Back To: Menu Bar
See Cultural Practices
HARVEST and POSTHARVEST Back To: Menu Bar
Mango trees may remain in production for 40 years or more. Fruits are usually picked after they develop some red, orange, or yellow color. Mangos will ripen and may be picked when the flesh inside has turned yellow, regardless of exterior color. The harvest season is usually between June and September in Hawaii, depending on variety. Fruit matures three to five months after flowering.
Mangos should be picked before they are fully ripe, at which time they soften and fall. The fruit bruises easily and must be handled carefully to avoid damage. They are ripened at room temperature and then refrigerated. Mature mangos keep fairly well under refrigeration for two to three weeks at 50 to 55°F
DISEASES Back To: Menu Bar
Anthracnose, Colletotrichum gloeosporioides (flowers, fruits)
Stem-end rot (fruits)
Sooty mold (leaves and fruits)
Powdery mildew, Oidium mungiferae (flowers, leaves, young fruit)
Tip burn (leaves; associated with potassium deficiency, water stress)
INSECTS Back To: Menu Bar
Mediterranean fruit fly, Ceratitis capitata
Oriental fruit fly, Bactrocera dorsalis
Mango weevil, Cryptorhynchus mangiferae
Scales, including Ceroplastes rubens, Pseudaulacaspis cockerelli
Red-banded thrips, Selenothrips rubrocinctus
Mango blossom midge, Dasineura mangiferae
Southern green stink bug, Nezara viridula
Mango shoot caterpillar, Penicellaria jocosatrix
Black twig borer, Xylosandrus cornpactus
Mites
PRODUCTION Back To: Menu Bar
India is the world’s largest producer of mangoes. It has been estimated that there are over 1000 commercial varieties in India, where mangos are often called the “king of fruits”.
According to FAO estimates, world mango production was 33.1 billion lb in 1989. India produced 63% of the total production. Other major producers were Mexico, Pakistan, China, Indonesia, Brazil and the Philippines.
Mangos are available year-round in various import markets. Countries such as Brazil, Peru and Venezuela are major suppliers during winter while Mexico, Haiti, India and the Philippines are major suppliers during the spring and summer seasons.
Mangos are consumed primarily in the producing countries. However, mango imports in European and North American markets have increased ten-fold since 1975. Demand has also steadily increased in other areas, such as the Middle East and Japan.
Florida is the main producer of mangos in the United States. In 1990, 2800 ac of mangos were planted in Florida, of which 2500 ac were harvested. The farm value of the 19.2 million lb produced was $4.7 million. Mangos are also produced in Hawaii and Southern California.
In one decade, US imports of fresh mangos increased from 42.4 million lb in 1981 to 139.8 million lb in 1990.
In 1990, the CIF (cost, insurance and freight) value of fresh mangos imported to the US was $65.2 million. Mexico was the largest supplier, accounting for 86.3% of the volume imported, followed by Haiti (13.2%). Sixty-one percent of the fresh mango imports entered the US between June and August in 1990.
The US also imported various processed mango products at a CIF value (including guava and mangosteen) of $11.8 million in 1990. Mexico supplied about 42% of the mangos, prepared or preserved. Brazil and the Philippines together supplied more than 52% of the mango and guava pastes and purees, cooked.
American consumers seem to prefer mangos with strong red color. Color can be increased by treating mangos with ethylene in banana ripening rooms.
In 1990, the US exported 15.8 million lb of mangos, guavas and mangosteens at an FAS (free alongside ship) value of $12.2 million. The Netherlands (49% of the quantity exported), Canada (27%) and the United Kingdom ( 20%) were the major destinations.
Mangos are popular as a backyard tree in Hawaii. For commercial production, it was estimated that there were 15 bearing acres of mango trees in 1989 and an additional 15 nonbearing acres. The bearing acres are on Maui (6 acres), Kauai (6 acres) and Oahu (3 acres).
Honolulu is the major market for mangos in Hawaii. In 1989, Honolulu arrivals of fresh mangos amounted to 42,000 lb, 79% of which came from Oahu. The other 21% were from Kauai and Maui. Most of the supply arrived in Honolulu from July to October. The supply of mangos available is even larger when backyard production is considered.
In 1991, there were 40 farms that produced mango for commercial sale. On these farms, there were 2,750 trees on 65 acres of land. There were 810 trees that produced 63,900 pounds of mangos that sold for 73 cents per pound. The total value of sales for mango in 1991 was $46,600.
Fresh mangos from Hawaii are not permitted in the US mainland, Japan and various other countries due to quarantine restrictions related to fruit flies and mango seed weevil.
REFERENCES Back To: Menu Bar
Chia, C.L., R.A. Hamilton and D.O. Evans. 1988. Mango. Commodity Fact Sheet MAN-3(A). Hawaii Cooperative Extension Service, CTAHR, University of Hawaii.
Neal, Marie C. In Gardens of Hawaii. Hawaii: Bishop Museum Press, 1965.
Wanitprapha, Kulavit, Kevin M. Yokoyama, Stuart T. Nakamoto and C.L. Chia. 1991. Mango Economic Fact Sheet #16. Department of Agricultural and Resource Economics, CTAHR, University of Hawaii.
Statistic of Hawaiian Agriculture 1991. Prepared by: Hawaii Agricultural Statistics Service, P.O. Box 22159, Honolulu, Hawaii, 96823-2159. December 1992. 105 pages.

Kent Mango Leaves Are Browning

Question:

I have a Kent mango and the leaves are browning. Does anyone know what is causing this? Please see photos.

Thanks!

Hardiness Zone: 10a

Advertisement

Robert from South Texas

Answer:

Robert,

I’m sorry that I can’t tell you what the exact problem is from your pictures. What I can tell you is that mango trees tend to fall prey to certain fungal diseases. The most common is anthracnose. Unfortunately, Kent mangos happen to be a variety that is very susceptible to anthracnose. Young leaves are particularly susceptible, especially in wet conditions, but the disease also attacks flowers, twigs, and young fruit. Symptoms appear as black spots on the leaves, or sunken black lesions on the fruit.

Verticillium Wilt is another type of fungus that can attack mango trees, especially if they are planted on sites where vegetables were previously grown. This soil-borne fungus is capable of surviving in a dormant state in the soil for as long as 15 years before becoming active. The fungus blocks the vascular system in plants, which sends them into a slow decline. Symptoms include leaves wilting and dying, often only on one side of the tree. Because the dead leaves tend to remain attached, the tree develops a burnt or “fired” appearance.

Advertisement

Deficiencies in manganese and iron can also result in mango decline.

I hope this information gives you some place to start.

Good luck!
Ellen

Insect Pests Disease & Care Of Mango Trees In South Florida

The Mango Mangifera indica L. from the Anacardiaceae family closely related to the cashew, spondias, and pistachio originated from India and Southeast Asia, lets discus Insect Pests Disease & Care Of Mango Trees In South Florida.

In South Florida Mangos are grown in Dade, Lee, Palm Beach Counties and along the coastal . Around the world Mangos are grown in tropical and subtropical lowlands and coastal areas with introduced to Cape Sable Florida in 1833.

Approximately 83 percent of Florida’s mango acreage is located in Miami-Dade County Florida

Mangos are produced around the world India, Pakistan, Indonesia, Mexico, Brazil, the Philippines, Australia, South Africa, Israel, Egypt, Puerto Rico, and Hawaii.
The mango tree is an evergreen tree that can grow from 30 to 100 ft tall.

Mango Hardiness Zone in Florida
Improper Care of Mango Trees in South Florida

The most common problems with mangos in the landscape is infrequent fertilization leading to macro and micronutrient deficiencies making mango trees susceptible to diseases.

Improper irrigation overhead watering and overwatering can cause diseases of the roots and foliage.

Improper mowing of grass with line trimmers or weed whackers around mango trees causing damage to bark making it susceptible to disease.

Misdiagnosing insect damage for fungus and mistreating for diseases thinking sooty mold is a disease.

Improper pruning creating improper growth.

Insect Pests of Mango Trees in South Florida
Red-banded thrips (Selenothrips rubrocinctus)
False oleander scale (Pseudaulacaspis cockerelli)
Pyriform scale (Protopulvinaria pyriformis)
dictyospermum scale (Chrysomphalus dictyospermi)
Florida Red scale (C. aoaidum)
Mites (e.g., Paratetranychus yothersii)
Florida Thrips (e.g., Frankliniella bispinosa)
Ambrosia beetles (Xylosandrus sp.).
Mediterranean fruit fly

Mango Decline by fungal pathogens (Botryosphaeria ribis and Physalospora sp.)
Mango Malformation caused by the fungus Fusarium mangiferae Britz,

For more info See:
Mango Growing in the Florida Home Landscape
Florida Crop/Pest Management Profile: Mango
Pruning Mango Trees
Insect Management in Mango
Mango Postharvest Best Management Practices Manual

NaturePest offers natural organic pest and disease control with fertilizing for your mango and fruit trees in South Florida.

Article Headline: Insect Pests Disease & Care Of Mango Trees In South Florida Article Description: The Mango Mangifera indica L. originated from India and Southeast Asia, lets discuss the Insect Pests Disease & Care Of Mango Trees In South Florida. Author Name: Franklin Hernandez Image URL: https://naturepest.com/wp-content/uploads/2016/06/Insect-Pests-Disease-Care-Of-Mango-Trees-In-South-Florida.jpg Publisher Name: Nature Pest

Disease control for mango tress in the home landscape is usually not warranted or should not be intensive. The easiest method for avoiding disease problems is to grow anthracnose-resistant varieties, plant trees in full sun where the flowers, leaves, and fruit dry off quickly after rainfall, not to apply irrigation water to the foliage, flowers, and fruit, and to monitor the tree for disease problems during the flowering and fruiting season. 1
The two major disease problems for mango trees in the home landscape are powdery mildew and anthracnose. Both these fungal pathogens attack newly emerging panicles, flowers, and young fruit. One to two early spring applications of sulfur and copper timed to begin when the panicle is 1/2 full size and then 10 to 21 days later will greatly improve the chances for fruit set and production. Usually, protecting the panicles of flowers during development and fruit set results in good fruit production in the home landscape. 1
Homeowners should contact their local UF/IFAS Extension office for recommended control recommendations for the diseases discussed below.

Anthracnose (Fig. 1,2)
Caused by Colletotrichum gloeosporioides
Anthracnose can occur on all parts of the mango tree. Leaf infection starts as small, dark, angular to irregular spots. These often coalesce to form large necrotic areas, which may crack. Infections on the flower panicle appear as small brown or black spots which enlarge
and often coalesce to cause the death of flowers. Small fruit are rapidly invaded by the fungus once they become infected. On nearly mature or ripe fruit, black spots coalesce to cover large areas, which may be sunken. Surface “tear staining,” a phenomenon caused by spores falling from an inoculum source above the fruit, may be apparent. 2

Fig. 3 Fig. 4 Fig. 5 Fig. 6
Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11
Fig. 12 Fig. 13 Fig. 14 Fig. 15

Fig. 3,4,5,6. Anthracnose on fruit circular lesions
Fig. 7. On mature fruits “tear stain” lesions
Fig. 8. Anthracnose “tear stain” lesions cracking
Fig. 9,10,11. Anthracnose symptoms on leaves
Fig. 12,13,14. Symptoms on inflorescence and panicles
Fig. 15. Symptoms on stem
Further Reading
Mango Anthracnose (Colletotrichum gloeosporioides), University of Hawai’i at Mānoa pdf 9 pages
Anthracnose of mango: Management of the most important pre‐ and post‐harvest disease, University of Florida TREC pdf 11 pages
Powdery Mildew (Fig. 17)
Caused by the fungus Oidium mangiferae
In severe attacks, the entire blossom panicle may be involved and fruit fail to set. Infected flowers, flower stalks, and young fruit become coated with the whitish powdery growth of the pathogen and the flowers and young infected fruits are similarly coated with the white fungal growth. Younger leaves may become distorted. On older leaves and fruit, infected tissue has a purplish-brown cast, as the white growth weathers away. The infection on fruit may also appear as an irregular blotch. Affected fruit may turn brown and fall off the tree. The disease is a particular problem in cool dry years. 2

Fig. 18 Fig. 19 Fig. 20 Fig. 21

Fig. 18. Fungal mycelium and spores on leaf surface
Fig. 19,20,21. Mildew on flowers, panicles and fruit
Further Reading
Mango Powdery Mildew, University of Hawai’i at Mānoa pdf 6 pages
Scab
Caused by Elsinoe mangiferae
Scab is a pathogen of young leaves and colonization is favored in cool, wet conditions. Signs of scab on leaves are small spots on the underside of leaves, which turn from dark-brown to gray. Leaves may become distorted and twisted if the infestation is heavy. Gray lesions on twigs may also be apparent. Fruit develops irregular, gray lesions which enlarge as it matures. The lesion centers become corky and cracked, and often exhibit the velvety growth of the fungus in moist weather. 2
Alga Leaf Spot (Fig. 22)
Caused by Cephaleuros virescens
This alga commences colonization late in the summer and progresses through the winter months. Initially hard to visualize, green, yellow-green, or rust colored leaf spots up to 5 mm in size become raised and roughly circular. Stems may develop cankers where infestation is high. The alga eventually produces rust-colored “spores.” These will give rise to more algae if not controlled with copper sprays. 2

Fig. 23 Fig. 24

Fig. 23,24. Green alga (Cephaleuros virescens) Kunze on citrus
Further Reading
Cephaleuros Species, the Plant-Parasitic Green Algae, University of Hawai’i at Mānoa pdf 6 pages
Leaf Spot (Fig. 25)
Caused by Pestalotiopsis mangiferae and Phyllosticta anacardeacearum
Both of these fungi cause leaf spot in mango, but with slightly different appearances. P. mangiferae spots (Fig. 25) are gray and irregularly shaped. They may range from a few millimeters to several centimeters in diameter. P. anacardeacearum leaf spots are bleached to white in color and can be numerous on leaves. Both fungi form black dot-like reproductive structures in the lesion centers. 2

Verticillium Wilt
Caused by Verticillium alboa-trum
This soil-borne fungus is more prevalent in trees planted in historic areas of solanaceous crop production. The fungus invades water-conducting structures in the roots, causing a persistent wilt, which is often one-sided on the tree. Brown or gray streaks may be observed in the vascular tissue once the bark is peeled away. Leaves may die for lack of water but remain attached for some time. Trees also may flush out with new shoots several months after collapse, apparently recovered from the infection. 2
Disorders
Mango Decline (Fig. 26)
(presumably caused by endophytic fungus or fungi)
Research to date suggests that mango decline is caused by deficiencies of manganese and iron. These deficiencies may predispose trees to infection by fungal pathogens (Botryosphaeria ribis and Physalospora sp.), which attack shoots, or by root feeding nematodes (Hemicriconemoides mangiferae). Leaf symptoms include interveinal chlorosis, stunting, terminal and marginal necrosis, and retention of dead leaves that gradually drop. Dieback of young stems and limbs is common and even tree death may occur. Increased applications of iron, manganese, and zinc micronutrients have been observed to reduce or ameliorate this
problem. 1

Fig. 27 Fig. 28 Fig. 29 Fig. 30
Fig. 31 Fig. 32 Fig. 33 Fig. 34

Fig. 27,28. Stem gummosis
Fig. 29. Internal stem necrosis
Fig. 30. Fruit splitting and bleeding
Fig. 31. Internal fruit dry rot
Fig. 32. Fruit mummification
Fig. 33,34. Trunk splitting
Further Reading
A reexamination of Mango Decline in Florida, University of Florida TREC pdf 5 pages
Mineral Treatment for Mango Decline, Archives of the Rare Fruit Council of Australia
Internal Breakdown
This is a fruit problem of unknown cause, which is also called jelly seed and soft nose. Generally, it is less of a problem on the calcareous (limestone) soils found in south Miami-Dade County and more common on acid sandy soils with low calcium content. The degree of severity may vary from one season to another. Several symptoms may appear including a softening (breakdown) and water soaking of the fruit flesh at the distal end while the flesh around the shoulders remains unripe, an open cavity in the pulp at the stem end, over-ripe flesh next to the seed surrounded by relatively firm flesh, or (4) areas of varying size in the flesh appearing spongy with a grayish-black color. This disorder is aggravated by over fertilization with nitrogen. If fruit have this problem, reduce the rate of nitrogen. In sandy and low- pH soils, increased calcium fertilization may help alleviate this problem. Fruits harvested mature-green are less affected than those allowed to ripen on the tree. 1
Further Reading
Internal Breakdown in Mango Fruit, University of Florida TREC pdf 12 pages
Mango Malformation
Caused by Fusarium mangiferae Britz
This disorder is caused by Fusarium mangiferae Britz, a fungus. Symptoms include the drastic shortening of panicles, giving them a clustered appearance and/or a shortening of shoot internodes. Affected panicles do not set fruit and eventually dry up and turn black. This disorder is not common in Florida, but homeowners should watch for it and immediately prune off affected flower panicles and shoots and destroy them. 1
Further Reading
Mango Malformation Disease, Queensland, Australia, Primary Industries and
Fisheries pdf
Further Reading
Dooryard Disease Control for Mangos in Florida, University of Florida Miami-Dade County Extension pdf
Mango Rachis Blight, Florida of Agriculture and Consumer Services pdf
Mango Diseases and Their Control, University of Hawai’i CTAHR pdf 5 pages

Mango

Description

Mango, Mangifera indica, is an evergreen tree in the family Anacardiaceae grown for its edible fruit. The mango tree is erect and branching with a thick trunk and broad, rounded canopy. The leaves of the tree are are shiny and dark green. They are either elliptical or lanceolate with long petioles and a leathery texture. The tree produces dense clusters of flowers with cream-pink petals on branched panicles. The mango fruit is roughly oval in shape, with uneven sides. The fruit is a drupe, with an outer flesh surrounding a stone. The flesh is soft and bright yellow-orange in color. The skin of the fruit is yellow-green to red. Mango trees can grow to a height of 45 m (148 ft) and can live for in excess of 100 years. Mango is believed to originate from India or Burma (Myanmar).
Mango leaf close-up
Mango foliage
Mango inflorescences
Ripening mangos
Mango fruits
Mango infolrescences
Mango foliage
Mango foliage
Mango canopy ‹ ×

Uses

Mango is commonly eaten as a fresh fruit. The fruit may also be processed to produce mango pickles or chutneys.

Propagation

Basic requirements Mango trees grow best in tropical or subtropical climates where there is no danger of frost and especially in areas where the rainfall over the four summer months (June to September) totals 75 to 250 cm (30 to 100 in) and is followed by 8 months of dry weather. The trees grow optimally at temperatures of 24–27°C (75.2–80.6°F) with a relatively cool dry season and where heat is highest during flowering and fruiting. Mangos will tolerate almost any soil as long as it is well draining. Optimal growth will be achieved in rich, deep, well drained, loams. However, very rich soils will promote vegetative growth at the expense of flower and fruit production and should be avoided. The trees also grow well in sand, gravel and limestone soils. The optimum soil pH is between 5.5 and 7.5. Trees should be positioned in full sunlight for optimal fruit production. Propagation Seeds Mango seeds are commonly used to produce rootstock or in the production of new cultivars. Seeds can be polyembryonic or monoembryonic. Polyembryonic seeds can produce between 3 and 10 seedlings from one seed, the majority of which will exhibit the characteristics of the parent plant. Monoembryonic seeds produce only one seedling from each seed and it usually does not breed true to type. Monoembryonic mango varieties are usually vegetatively propagated by grafting onto polyembryonic rootstocks. Seeds are collected from fully ripe fruit before chilling. The kernel is then removed from the endocarp and is planted within 24 hours of collection due to a rapid degeneration in seed viability. Mango seeds should be planted to a depth of 2 cm (0.8 in) and should be positioned on their sides to promote a straight growth habit. Monoembryonic seeds should be planted to a depth of 1-2 cm (0.4-0.8 in) in 1 to 5 gallon pots containing a well-draining potting soil. Polyembryonic seeds are usually planted in beds to allow space for the multiple seedlings. It is common to plant above a root barrier to facilitate the removal of seedlings from the bed when the time comes to pot them. Generally only 3-4 of the most vigorous seedlings are selected and potted up. Potted seedlings are usually raised under 50 to 80% shade and hardened to the sun prior to plating in the field. Vegetative propagation Desirable mango varieties can be vegetatively propagated by budding and grafting to ensure that the new tree shares the genetic characteristics of the parent. Twigs for propagation are best collected from healthy, mature trees when the trees are beginning a growth flush but when most of the terminals are still dormant. The twigs for propagation quickly lose their viability so it is important to keep them moist and cool after cutting and make the grafts immediately. The twigs should be of the same girth as the rootstock wood onto which it will be grafted and at least the thickness of a pencil to support the cuts. There is no preferred method of grafting the wood onto the rootstock and methods tend to vary by region. Veneer grafting, V-grafting and chip budding are all suitable methods for joining the scion wood to the rootstock. Graft unions are usually complete 2–3 weeks after they are made. Depending on the grafting method, the buds on the grafted scion may require forcing. This is achieved by cutting the rootstock horizontally 2–5 cm (0.8–1.9 in) above the graft on the same side as the scion. When a scion bud has grown several centimeters, the rootstock wood can be cut back close to the scion. Transplanting Mango trees are usually planted out in the field when they are approximately 12 months old. The seedlings should reach a height of at least 1 m (3.3 ft). If the trees are to be irrigated then they are best planted out in early Spring. If no irrigation is available then they should be planted at the beginning of the wet season. Planting holes should be at least 60 cm (2 ft) deep and another 60 cm (2 ft) wide to accommodate the root ball of the tree. Fertilizer should not be added to the the planting hole at time of plating as it can burn sensitive roots. Tree spacing depends on the variety being grown but is generally between 10.5 and 18 m (34 to 60 ft). The tree canopy can be cut back up to 75% after planting to reduce water stress and promote root development. General care and maintenance Mango trees are easy to maintain once established. They are tolerant of drought but will perform best if irrigated during dry spells. Mango planted in the home garden does not generally require regular fertilization. if leaves are beginning to look pale or yellow, a balanced fertilizer may be applied once or twice every year. When grown commercially, mango trees require regular pruning to open up the canopy. Pruning keep the canopy at a manageable size and also promotes good air circulation around the leaves and fruit, reducing the incidence of disease. Harvesting Mango fruits are usually ready for harvest 4-5 months after flowering. Fruits that are ready for harvesting will snap easily from the tree. If the fruit does not dislodge with a slight pull then it is not fully mature and should be left to ripen fully. Fruits can be harvested by hand or, in commercial plantations, with the aid of special fruit picking devices. Mango fruit is delicate and easily bruised and must be handled carefully. Mango sap is very caustic and additional care must be taken during harvest to prevent sap coming into contact with the skin of the fruit or it will result in dark blemishes.

Bally, I. S. E. (2006). Mangifera indica. In Elevitch, C. R. (ed.) Species profile for Pacific Island Agroforestry. Permanent Agricultural Resources (PAR). Available at: http://www.agroforestry.net/images/pdfs/Mangifera-mango.pdf. . Free to access. CABI Crop Protection Compendium. (2015). Mangifera indica (mango) datasheet. Available at: http://www.cabi.org/cpc/datasheet/34505. . Paid subscription required. Dirou, J. F. (2004). Mango growing. NSW Department of Primary industries. available at: http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0006/119787/mango-growing.pdf. Accessed 17 February 15]. Free to access. Morton, J. (1987). Mango. In: Fruits of warm climates. Creative Resource Systems, Inc. Available at: http://www.hort.purdue.edu/newcrop/morton/index.html. . Free to access. Ploetz, R. C., Zentmyer, G. A., Nishijima, W. T., Rohrbach, K. G. & Ohr, H. D. (eds) (1994). Compendium of Tropical Fruit Diseases. American Phytopathological Society Press. Available at: http://www.apsnet.org/apsstore/shopapspress/Pages/41620.aspx. Available for purchase from APS Press. Sauls, J. W. & Campbell, C. W. (1994). Mango propagation. University of Florida Cooperative Extension Service. Available at: http://university.uog.edu/cals/people/PUBS/MANGO/Mg05300.pdf. . Free to access.

नए लेख

आम के 9 प्रमुख रोग व उनका नि‍दान कैसे करें

The mango (Mangifera indica) is an evergreen fruit tree. It is national fruit of India. It is a juicy stony fruit belonging to family anacardiaceae. The mango is native to South Asia. India accounting 42 % sharing in total world mango production. Mango is a rich source of vitamin C. dried mango skin and its seeds are also used in ayurvedic medicins.

Mango leaves are used to decorate archways and doors in Indian houses. Mango also used for achar making, amchoor and for vegetable. Mango suffers from several diseases at all stages of its life. The major diseases of economic importance in India are:

1. Powdery Mildew (Oidium mangiferae)

The symptoms can be noticed on the inflorescence, stalk of inflorescence, leaves and young fruits. The characteristics symptoms of disease are white superficial powdery growth of the fungus on these parts.

The effective flowers may fall prematurely and young fruits may remain on the tree until they reach up the marble size and then drop prematurely. Dropping of unfertilized infected flowers and young fruits leads to serious crop loss (20-80%).

Control:-

  1. Pruning of diseased leaves and malformed panicles reduces primary inoculums.
  2. Three sprays of systemic fungicides during flowering season are recommended at 12-15 days intervals. 1st spray is recommended when there is 25% flowers opening.

2. Anthracnose/ Blossom Blight (Colletotrichum gloeosporioides)

Anthracnose manifests on different parts of mango tree. On the inflorescence, the earliest symptoms of the disease are the production of blackish brown specks on peduncles and flowers. Small black spots appear on the panicles and open flowers, which gradually enlarge and cause death of flowers.

The infected flowers fall off, leaving the more persistence spikes on the peduncles, this leads to serious crop loss (10-90%). In leafy anthracnose Characteristics symptoms appear as oval or irregular brown to deep brown spot of various sizes scattered all over the leaf surface.

Under damp conditions, the fungus grows rapidly. Young leaves are more prone to attract than the older ones. Insect attack may facilitate the entry of pathogen resulting into heavy incidence of disease.

Control:-

  1. Diseased leaves, flowers, twigs and fruits lying on the floor of the orchard should be collected and all infected twigs from the tree should be pruned and burnt.
  2. Blossom infection can be controlled effectively by two to three sprays of contact or systemic fungicides during spring season at 12-15 days interval.

3. Mango malformation (Fusarium mangiferae)

Malformation is a serious threat to the mango growing areas of Pakistan as it causes crop loss upto 70%. Recent findings have demonstrated that the disease may be of fungal origin. Two distinct types of symptoms described by the workers are vegetative malformation (MV) and floral malformation (MF).

Vegetative malformation is more pronounced in young seedlings as well as seedling trees than in the grafted plants. The affected seedlings developed excessive vegetative branches, which are of limited growth, swollen and have very short internodes.

Malformation of inflorescence (MF) is a disease of inflorescence. The most characteristic symptoms of (MF) are the reduction and compact of internodes giving malformation a broom like appearance.

Control:-

At present, no definite control measures for mango malformation can be advocated. However the following may reduce the incidence of malformation

  1. It is advisable to avoid scion stick from trees bearing malformed inflorescence for propagation.
  2. Only certified saplings should be used for propagation.

iii. As soon as the disease symptoms are well expressed, the affected terminals should be pruned along with the contiguous 15-20cm apparently healthy portion and burnt.

4. Alternaria leaf spot (Alternaria alternata)

Symptoms first appear as small, brownish circular spots on the surface of leaves. Later on, high concentration of brown black spots occurs evenly over the leaf lamina. Symptoms are more prominent on the lower side of the leaves. The tender leaves are found to be more susceptible than mature ones.

Control:-

  1. The disease can be controlled by regular field spray program including copper based fungicides.

5. Bacterial Canker (Xanthomonas mangiferae)

On leaves, minute water soaked irregular to angular raised lesions is usually crowded at the apex. On young leaves halos are larger and distinct, while on older leaves, they are narrow could be observed only against light. Under severe infections, the leaf turns yellow and drop off.

Control:-

  1. Regular inspection of orchards, sanitation and seedling certification are recommended as preventive measures against the disease.
  2. Spray of copper based fungicides has been found effective in controlling bacterial canker.

6. Stem End Rot (Lasiodiplodia theobromae, Phomospsis mangiferae, Dothiorella doninicana)

The fruit while ripening suddenly becomes brown to black typically at stem end. Within two three days whole fruit becomes a black and disease progress downwards, thus involving half of the area of the fruits.

Though the flush of the whole fruit often wrinkles are also observed. Affected skin remains firm but decay sets into the pulp below and emits unpleasant odour.

Control:-

  1. Prompt and proper handling of the fruit can minimize disease incidence.
  2. Fruit should be harvested with 10mm stalk.
  3. Pre-harvest sprays of any systemic fungicides or copper based fungicides reduce the incidence of SER.
  4. Post harvest dip of fruit in hot water supplemented with carbendazim or thiophanate methyl (0.05%) for 15 minutes at 52±1oC control the disease.

7. Die back (Lasiodiplodia theobromae, Natrassia mangiferae)

The disease is noticeable throughout the year but it is most conspicuous during October and November. It is characterized by drying up of twigs from top to downward particularly in the older trees followed by drying up of leaves which gives an appearance of fire scorch.

The upper leaves lose their color and gradually dry. Drying of the whole leaf is accompanied by upward rolling of the margin. Such leaves shrivel, fall off within a month leaving the shriveled twigs all together bare, which is the characteristic symptom in the advance stage of the disease.

Control:-

  1. Pruning of affected twigs (3’’ below the infection site) followed by spraying of copper based fungicides is the most effective method for the control of disease.
  2. In severe cases, the soil amendment with the removal of soil up to 9 inches deep under the canopy of the diseased tree and refilling with the canal silt, recommended doses of chemical fertilizers and FYM with pruning of affected twigs followed by three consecutive sprays of copper based fungicides at 15 days interval is also recommended.

8. Gummosis (Lasiodiplodia theobromae)

About 30-40% of young mango trees are affected by the gummosis especially when the mango tree is planted in sandy soil but its prevalence has also been noticed in other mango growing soils.

The diseases is characterized by the presence of profuse oozing of gum on the surface of affected wood, bark of the trunk and also on larger branches but more common on the crack branches. In severe cases, droplets of gum trickle down on stem and bark turns dark brown with longitudinal cracks.

Control:-

  1. The disease can be controlled with the regular sprays of copper based fungicides.
  2. The diseased bark / portion should be removed, cleaned and covered with copper based fungicides paste.
  3. Application of copper sulphate 500g in the sandy soil around the tree trunk is also advocated.

9 Root rot (Rhizoctonia )

Infection occurs at/or below the ground level the circular to irregular water socked patches. These patches enlarge and ultimately girdle the entire base of the stem. On account of rotting, the diseased tissues become soft, dark brown or black.

Control:-

  1. Soil treatment with Thiophanate methyl, carbendazim or copper oxychloride @ 2g/ft2 is recommended.
  2. During the growing period any copper based fungicide should be sprayed on the plants.

Authors

Jitendra Sharma, G.S. Rathore, Richhapal Kumawat and Rajendra Jangid

Sri Karan Narendra Agriculture University, Jobner-303329

email: This email address is being protected from spambots. You need JavaScript enabled to view it.

There are a few common mango tree diseases in the United States. The diseases, if left unchecked, can infect not only the homeowner’s backyard fruit trees, but those of neighboring yards as well, so quick action is always best. If you’re a fan of the luscious tropical mango fruit, the following information will help you identify diseases that may invade your trees.

Athracnose Disease

One of the most serious diseases is athracnose. It is caused by the Colletotrichum gleosporioides fungus.

Symptoms

Symptoms of this disease include dark leaf spots, blossom blight and fruit rot. The spots that appear on the leaves are small and black or brown. These spots can be small dots or as large as a half-inch in diameter in older trees. The spots may appear much larger in younger trees, and entire branches will have leaves that wither and die.

The infection may also appear when the tree is in bloom. The symptoms are brown spots appearing on the flowers, which then turn brown and fall off. Buds are also affected, turning brown, enlarging and then dying off. In regards to the fruit, the fungus infects the skin of the fruit. As it begins to ripen, black spots will appear. The fungus not only causes rotting of the outer skin, but the interior of the fruit as well.

How It Spreads

This fungus is spread from spores that live in dead leaves on the ground and transferred to the mango through rain or irrigation splashing upon the tree. Once the tree is infected, the spores are transmitted to other branches via water droplets. During lengthy, rainy springs the disease is readily transmitted throughout entire orchards.

Treatment

The treatment is two-pronged. First, it is important to keep the area under the mango tree free of debris and fallen fruit. Second, the trees may be treated with a copper fungicide at several intervals, which include starting at the beginning of the growing period and ending post-harvest.

Verticillium Wilt

Verticillium wilt is caused by the Verticillium albo-atrum and V. dahlie fungus that lives in the soil. Mango trees that are planted in areas previously used for growing vegetables, such as tomatoes, appear to be most susceptible.

Identifying Symptoms

The symptoms of a tree infected with this fungus include leaves on one side of the tree wilting, then turning brown and dying. The leaves usually stay attached to the tree, making this disease somewhat easy to identify. To positively identify this disease, a branch is cut from the tree then a longitudinal incision is made. The inside of a tree infected with verticillium wilt will have a brown appearance due to vascular degeneration inside.

Prevention and Prolongation of Life

Keeping mango trees properly pruned, watered, and fed help keep the tree healthy and better able to fight off an infection. Most trees infected with verticillium wilt will eventually die and have to be removed from the landscape. However, you can try to prolong the life of the mango by pruning off the affected areas as soon as you notice the problem. Don’t replant back in the same area where verticillium wilt has caused passed problems.

Powdery Mildew

Powdery mildew is caused by the Oidium mangiferae fungus and transported through the wind. It appears when there are prolonged periods of cool, dry temperatures.

Signs of the Disease

The symptoms of the disease can be identified with the appearance of a white, powdery-like substance on the panicles, new fruit and the undersides of new leaves. This disease can cause premature leaf and fruit drop and can decimate a crop. Mature leaves that are infected have spots that appear a purplish-brown color. This occurs as the white fungus begins to disappear.

Treatment and Prevention

The treatment for this fungus is a copper fungicide program that begins in early spring just as the flowers develop and extends to the end of the crop season. Prevent the problem by planting in the warmest area of your landscape, pruning so the mango has good air circulation, and keeping the area underneath the tree free of plant debris, fallen fruit, and weeds.

Red Rust

Red Rust

Red rust, also called algae spot, is caused by a parasitic alga, Cephaleuros spp., and usually doesn’t cause any serious problems for the tree other than cosmetic ones. The problem is spread and most severe when conditions are humid, warm, and rainy.

Identifying the Problem

One of the symptoms of this disease is the appearance of dozens of tiny, rust-colored spots on the leaves. If left unchecked, the disease can spread from the leaves to the stems and bark of the tree. Red spore masses will thicken these areas and cause cankers, which will eventually have to be removed by pruning. Prune back into a healthy portion of wood. Always sterilize your pruning blades before and after making cuts so you don’t infect healthy sections of the tree.

Treat With Copper Fungicides

The treatment for this disease is a program of copper fungicides starting in the spring and applied periodically throughout the growing season. Organic foliar fungicides have not been effective in eliminating this disease.

Phoma Blight

Phoma blight (Phoma glomerata) is a soil-borne fungal disease that shows it effects only on older mango leaves. The fungal spores attach to the leaves when water from rain or irrigation hits the infected soil causing it to splash up and upon the tree’s foliage. If left untreated and in severe cases, phoma blight leads to total leaf drop and shriveling of the affected branches.

Initial Symptoms

When the fungus first attacks the leaves, symptoms show as small, discolored yellowish and brownish spots eventually covering the entire surface. As the fungal spores continue to develop, the spotting grows in size and area, with the coloration changing to a rusty brown and the centers can take on a grayish color.

Disease Prevention and Treatment

Keeping the mango properly fed and healthy helps prevent phoma blight, as well as keeping the area under the tree clean, removing falling foliage and fruit. When watering, try to keep the wet soil from splashing on the tree. Treat infected trees with a copper fungicide, making sure to cover all surfaces of the tree when spraying. Repeat the treatment every 14 to 20 days.

Dieback in Mangos

Dieback in mangos can be a serious problem severely affecting the fruit and in severe cases, kill the entire tree. The airborne fungus Lasiodiplodia theobromae infects the tree and causes the foliage, stems, and branches to start browning and dying from the top down.

Common Symptoms

Trees can look almost like they’ve been burned in a fire. Eventually, the foliage drops from the tree. As the problem progresses, a gummy, yellowish to brown substance oozes from the bark. Though dieback occurs throughout the year, it is most common during wet, winter months.

Pruning and Prevention

At the first sign of the problem, gardeners should prune off all affected branches and stems, making sure to cut back several inches into healthy wood. Make sure you use sterilized pruning tools so you don’t transfer disease into healthy wood. To help control and prevent further infection, spray the entire tree as well as the cut ends of branches with a copper fungicide.

Bacterial Canker or Bacterial Black Spot

Bacterial canker, also called bacterial black spot, caused by the bacteria Xanthamonas campestris, can sometimes be a serious disease affecting all portions of the mango, especially the fruit. The bacteria enters various parts of the mango through wounds and rapidly spreads to other portions of the tree as they touch each other. The disease is most severe and spreads rapidly during springs where the weather is cool and rainy. Cultivars such as Langra, Totapuri, and Mallika are types more susceptible to infection.

Symptoms of Disease

First signs of the disease show as dark-colored water spots on the foliage, and over time, the spots grow larger forming cankers. The cankers eventually affect the tree’s twigs and immature fruit. Lesions on the fruit turn black and ultimately split open releasing a contagious gummy substance that contains the spores of the bacteria.

Early Treatment and Prevention

Early treatment work best and gardeners should prune off affected areas of the tree, making sure to cut back several inches into healthy wood. To keep from transferring the disease to healthy portions of the tree, make sure to sterilize your pruning tool blades before doing any pruning.

Once infected, spray all portions of the mango with a copper fungicide and treat every 10 days. Keeping the area under the tree free of weeds and fallen debris helps prevent the problem.

Sooty Mold

Sooty mold is a fungus carried by the wind and attaches itself to all areas of the mango, including the fruit that have sticky honeydew on them.

Signs of Sooty Mold

A black, soot-like substance covers the affected areas of the tree and is a sign of an infestation of sap-sucking insects, like aphids, that secret honeydew.

Treat According to Severity

In most cases, sooty mold isn’t a serious problem and only creates cosmetic problems, so treatment isn’t necessary. Treating the insects with an insecticidal soap usually controls the problem from occurring.

In severe cases of sooty mold where it covers a large portion of the foliage and twigs, pruning off the affected branches and discarding the trimming in a garbage bag removes the moldy areas from the tree. You can also use a mild dishwashing soap mixed in water and wash the mold from the leaves.

Mango Malformation Disease

Mango malformation isn’t a very common problem in the U.S., but gardeners should be on the lookout for signs of the disease as the tree starts blooming. The fungus Fusarium mangiferae is the source of the problem and affects the developing flower panicles. Scientists are still studying the disease and it’s thought to be spread by windy conditions. The disease is also spread long distances through vegetative propagation materials (grafts), contaminated pruning tools, and mango bud mites.

Disease Prevents Fruit Development

The panicles develop with a short, stubby, and clustered appearance with the fruit never developing. Flowers eventually dry up, turn black and die.

How to Treat and Prevent

Gardeners should prune off affected panicles and shoots as soon as they notice the problem and discard in a garbage bag so the fungus doesn’t affect healthy portions of the plant. Make sure to sterilize your pruning tool blades before doing any trimming. If insects become a problem, spraying the tree with an insecticidal soap should control the problem. Periodically spraying the entire tree with a copper fungicide helps prevent the problem.

Managing Your Mango Tree’s Health

Manage most mango tree diseases by cleaning up fallen fruit, dead leaves, and branches at the end of the growing season and by periodic applications of fungicides. However, it’s impossible to eliminate all diseases because some fungi may remain dormant in the soil for several years or spread by neighboring stands of trees. At the first sign of infection, begin a regimen of fungicide applications. If there are no signs of improvement, contact your local Cooperative Extension office or the nursery where you purchased your trees for a correct diagnosis of the disease.

How To Manage Mango Disease: Tips For Treating A Sick Mango Tree

Mangos have been cultivated in India for more than 4,000 years and reached the Americas in the 18th century. Today, they are readily available at many grocers, but you’re even luckier if you happen to have your own tree. Delicious they may be, but the trees are susceptible to a number of mango tree diseases. Treating a sick mango means correctly identifying mango disease symptoms. Read on to find out about diseases of mangos and how to manage mango diseases.

Mango Tree Diseases

Mangos are tropical and sub-tropical trees that thrive in regions with warm temperatures. Indigenous to India and Southeast Asia, trees are particularly susceptible to two diseases of mango: anthracnose and powdery mildew. Both of these fungal diseases attack emerging panicles, flowers and fruit.

Of the two diseases, anthracnose (Colletotrichum gloeosporioides) afflicts mangos most severely. In the case of anthracnose, mango disease symptoms appear as black, sunken, irregularly shaped lesions that grow resulting in blossom blight, leaf spotting, fruit staining and eventual rot. The disease is fostered by rainy conditions and heavy dews.

Powdery mildew is another fungus that afflicts leaves, flowers and young fruit. Infected areas become covered with a whitish powdery mold. As leaves mature, lesions along the midribs or underside of the foliage become dark brown and greasy looking. In severe cases, the infection will destroy flowering panicles resulting in a lack of fruit set and defoliation of the tree.

Mango scab (Elsinoe mangiferae) is another fungal disease that attacks leaves, flowers, fruit and twigs. The first signs of infection mimic the symptoms of anthracnose. Fruit lesions will be covered with a corky, brown tissue and leaves become distorted.

Verticillium wilt attacks the tree’s roots and vascular system, preventing the tree from up-taking water. Leaves begin to wilt, brown, and desiccate; stems and limbs die back; and the vascular tissues turn brown. The disease is most damaging to young trees and may even kill them.

Parasitic algal spot is another infection that more rarely afflicts mango trees. In this case, mango disease symptoms present as circular greenish/grey spots that turn rust red on the leaves. Infection of stems can lead to bark cankers and stem thickening and death.

How to Manage Mango Disease Problems

Treating a sick mango for fungal diseases involves using a fungicide. All susceptible parts of the tree should be thoroughly coated with the fungicide before infection occurs. If applied when the tree is already infected, the fungicide will have no effect. Fungicide sprays need to be reapplied on new growth.

Apply fungicide in the early spring and again 10-21 days later to protect the panicles of blossoms during development and fruit set.

If powdery mildew is in evidence, apply sulfur to prevent the spread of the infection to new growth.

If the tree becomes infected with verticillium wilt, prune out any infected limbs. Mango scab generally doesn’t need to be treated since an anthracnose spray program also controls scab. Algal spot will also usually not be an issue when copper fungicides are periodically applied during the summer.

To reduce the risk of fungal infections, grow only anthracnose resistant cultivars of mango. Maintain a consistent and timely program for fungal application and thoroughly cover all susceptible parts of the tree. For assistance with treatment of disease, consult your local extension office for recommended control recommendations.

Leave a Reply

Your email address will not be published. Required fields are marked *