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).


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.


References

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/pd.... [Accessed 17 February 15]. Free to access.

CABI Crop Protection Compendium. (2015). Mangifera indica (mango) datasheet. Available at: http://www.cabi.org/cpc/datasheet/34505. [Accessed 17 February 15]. Paid subscription required.

Dirou, J. F. (2004). Mango growing. NSW Department of Primary industries. available at: http://www.dpi.nsw.gov.au/__data/asse.... 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/mo.... [Accessed 17 February 15]. 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/shopap.... 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.... [Accessed 29 April 15]. Free to access.


Common Pests and Diseases

Algal leaf spot
Cephaleuros virescens

Symptoms
Orange rusty spots on both upper and lower leaf surfaces which may coalesce to form large irregularly shaped patches; scraping away the orange spots reveals a grayish discoloration of the leaf lamina underneath
Cause
Alga
Comments
Disease affects many fruit trees in the tropics; infection is unsightly but often harmless
Management
Ensure that trees are properly pruned and fertilized to promote vigor; remove all weeds from around tree bases; employ a wider tree spacing to increase air circulation around the trees; badly infested trees can be treated with copper containing fungicides

Bacterial black spot (Bacterial canker)
Xanthomonas campestris

Symptoms
Angular, water-soaked spots on leaves which coalesce and turn black; black cankerous lesions on stems which crack and exude a gummy substance; irregular black lesions on fruits which extend into the flesh and exude gum; fruits dropping from plant
Cause
Bacterium
Comments
Bacterial black spot is found in most tropical and subtropical areas where mango is grown
Management
Provide windbreaks for plants; prune out infected twigs; protective sprays of copper during wet weather help to protect plants from the disease

Anthracnose
Colletotrichum gleosporioides

Symptoms
Small, dark spots on flowers; spots coalesce to cover entire panicle; infected flowers dropping from tree; dark flecks or spots with yellow halo on young leaves; dark, irregular, sunken lesions on fruit; fruits dropping from tree before ripe
Cause
Fungus
Comments
Disease emergence favored by wet conditions; serious disease of mango wherever it is grown
Management
Susceptible mango varieties should be protected with fungicide in commercial production and the timing of the applications are critical to successful control; appropriate fungicide should be applied during flowering and fruit development

Powdery mildew
Odium mangiferae

Symptoms
Gray-white powdery growth on leaves, flowers and/or fruit; curled, distorted shoots; fruit aborted and dropping from tree
Cause
Fungus
Comments
Found in all mango growing regions; outbreaks sporadic but can be severe
Management
Fungicides are very effective at controlling powdery mildew if applied at the first sign of the disease; chemical sprays only need be applied at flowering and fruit set

Phoma blight
Phoma glomerata

Symptoms
Angular or irregular brown lesions on old leaves; lesions may develop gray centers and dark margin; withering leaves; defoliation of tree
Cause
Fungus
Comments

Pink disease
Erythricium salmonicolor

Symptoms
White, silk-like threads at forks of branches which coalesce to form a pink crust during wet conditions; twigs and branches above this site may be killed and foliage will begin to dry out and die; orange pustules may be present on infected bark
Cause
Fungus
Comments
Pink disease is a destructive disease of mango grown in the wet tropics
Management
If pink disease is identified the recommended treatment is an application of an appropriate fungicide which can be applied by spraying or painting onto infected bark with a paintbrush

Sooty mold
Several species of fungus

Symptoms
The leaves, twigs, inflorescence and fruits are covered with shiny black and sticky growth of fungal mycelium. The sooty mold won't cause any direct infection to plants, but it may effect the photosynthetic process which may cause premature aging and death of leaves. Also plants may show stunted growth.
Cause
Fungus
Comments
Sooty mold mainly develops on honey dew secreted by sap sucking insects like whiteflies, aphids, leaf hoppers, scale insects, mealybugs and psyllids. Also this insects are always associated with ants.
Management
1. If plants are small wash mold with strong stream of water
2. Spraying starch also removes sooty mold
3. Control sap sucking insects
4. Also keep the trees free from ants by applying a sticky compound around the trunk .

Mango tree borer
Batocera rufomaculata

Symptoms
Mango tree borer damage may first be noticed as circular holes in the bark. This damage indicates that the tree has been attacked by borers which have chewed exit holes in the wood. Mango tree borers feed on the bark of twigs and chew green growing tips; when feeding damage is severes, branches may be killed and the main stem of the tree may collapse; insect frass (feces) collects in cracks in the bark and around the base of the tree; holes become visible in the bark.
Cause
Insect
Comments
Mango tree borers are a pest of mango trees in many parts of Asia, Africa, Central America, the Caribbean and the Solomon Islands; female tree borers lay their eggs in an incision made in damaged mango bark; larvae bore through the wood as they feed and eventually pupate within the tree; adult insects emerge from an exit hole that they cut in the wood. adult insects are 25–55 mm long with distinctive long antennae which extend the length of the body
Management
Application of appropriate insecticide to the trunk and branches of the tree when adult insects are present acts to kill any eggs and larvae that are present; insecticide applied to growing twigs and green shoots may deter adult feeding; probing injury sites with a knife or piece of wire can help to destroy larvae and eggs

Mango mealybugs
Drosicha mangiferae

Symptoms
Both nymphs and female insects sucks sap form all parts mango tree (i.e., tender leaves, shoots and inflorescence). The infected inflorescences may dry up affecting the fruit set and may cause fruit drop. Severely infected plants may show wilting and thereby affect fruit setting.
Cause
Insect
Comments
a. Mealybugs lay eggs in soil near tree trunk.
b. The mealybugs secrete the honey dew which causes sooty mold.
c. It feeds on wide range of plant species.
Management
1. Collect and burn fallen leaves and twigs.
2. Flooding orchard with water during October kills egg present in soil. Also deep ploughing in November exposes egg to sunlight.
3. After hatching the nymphs start climbing tree and suck sap. To avoid this band the tree trunks with polythene sheet (400 gauge, 30 cm wide) at a height of about 30 cm from the ground level and apply grease at the lower edge of band. Or you can use Funnel Type Slippery Traps.
4. To control insects already on tree you can spray fish oil rosin soap or azadirachtin (neem products).
5. Also soil application of the spores of the fungus, Beauveria bassiana helps in reducing mealybug population.
6. If infestation is severe you can spray suitable insecticides

White Mango Scale
Aulacaspis tubercularis

Symptoms
Scale insects suck the sap from leaves, branches and fruits which causes defoliation, drying up of young twigs, poor blossoming and also affect the quality of fruits by causing conspicuous pink blemishes. Infestation of young plants results in retard growth. In case of severe infestation the fruits may fall prematurely, whereas the mature fruits are reduced in size.
Another major problem with scale insect is the development of sooty mold due to honeydew secretion.
Cause
Insect
Comments
The insect have wide host range and can be seen in all mango growing countries like Ghana, Kenya, Madagascar, Mozambique, South Africa, Tanzania, Uganda, Zimbabwe, Australia, China, India, Indonesia, Malaysia, Pakistan, Philippines, Sri Lanka, Taiwan, Thailand, Japan, Egypt, Iraq, Israel, Italy and in many South American countries.
Management
Remove the infested plant parts and burn them. Spraying emulsive oil or suitable insecticides at recommended quantity will helps in reducing scale population.

Fruit fly
Ceratitis cosyra
Bactrocera obliqua
Bactrocera frauenfeldi
Anastrepha spp.

Symptoms
The adult female flies lay egg just under the skin of semi repine fruits. The maggots develop and feed inside the fruit, causing the flesh to turn brown and soft which emits foul smell. This damage also act as entry site for fungal and bacterial pathogens.
Cause
Insect
Comments
The mature maggots fall out of the fruits and pupate in soil.
Management
1. Collect the fallen fruits and destroy them.
2. Also harvest fruits early to reduce flies damage .
3. Use traps to monitor fruit flies. Traps can be purchased in the market or one can prepare themselves. Take plastic container with lids (one quarts yogurt container is fine). Drill holes (10 to 16 holes) that are 3/16-inch in diameter around the upper side of the container. Add 1 to 2 inch of pure apple cider vinegar (not flavored one) and a drop of unscented liquid dishwashing soap into the container. Hang the container in shade near berry trees before fruits ripening and check the traps frequently for flies. Change the vinegar every week.
5. Spraying protein bait under leaf surface attract flies to single spot which make easier to kill them.
4. If infestation is severe spray suitable insecticide.

Mango hoppers
Idioscopus clypealis
Idioscopus nitidulus
Amritodus atkinsoni

Symptoms
Reduced plant vigor; sticky substance coating leaves; may be a growth of sooty mold on sticky residues; curling and drying leaves
Cause
Insects
Comments
Insect emergence favored by shady and humid conditions