MANGO (Mangifera indica)

The mango tree is native to southern Asia. It is an ever green tree in the family of Anacardiaceae. Its height varies according to variety and management. Mango fruits of the various varieties differ greatly in shape, size, appearance and internal characteristics. The leathery skin is waxy and smooth. When ripe, the fruit turns pale green, orange, yellow marked with red, depending on the variety.  Mango is rich source of Vitamin C  and beta carotene. The vitamin content depends on the variety and maturity of the fruit. When the mango is green the amount of vitamin C is higher, as it ripens the amount of beta-carotene (Vitamin A) increases.

Mango fruits and  Mango tree

Mango fruits (Tommy Atkins)                                                             Mango tree

Varieties and Descriptions

Variety Description Attributes
Ngowe It is large oblong longer than broad and slender with a very prominent hook-like beak a pointed projection at the tip of a fruit at the apex tip of shoot. From pale green, the fruit develops to a most attractive yellow to orange colour when ripe. The deep yellow flesh is of excellent quality and virtually free from fibre. Coastal variety but can also be grown in medium altitude areas.

Well adapted in areas below 1000m asl.

Good quality, most popular for export and juice processing

Susceptible not resistant to powdery mildew

Boribo Large and long orange-red. The fruit shoulders are only slightly curved with deep orange flesh. The internal fruit quality is good to excellent; the flesh is deep orange  in colour, virtually free from fibre, juicy, and of a very strong typical mango flavour Higher yielder, good quality for export. Suitable for canning.

Fairly anthracnose resistant but susceptible not resistant to powdery mildew

Batawi Very large, round fruit, light purple-green in colour. The flesh is pale orange in colour. Good quality fruit with little fibre.

Resistance to anthracnose but very susceptible to powdery mildew.

Apple Fruits are large, round and apple shaped. Have rich yellow- orange to red colour when ripe. They are fleshy , juicy fibreless and with firm texture Adapted to coastal and lowland areas.

Very susceptible to rust in higher altitude.

Matures early in the season between November and January.

Sabine A local selection with attractive elongated fruits. The fruit is orange, yellow or red in colour. Fairly good resistance to anthracnose and powdery mildew

Suitable for higher elevations

Recommended for use as rootstock .

Matures at around January and February.

Vandyke The fruits are small in size. They have attractive bright red colour, good internal quality and medium firm skin. The tree yields poorly and suffers heavy drops.

Maturity period is around January and February. Susceptible to anthracnose.

Parwin The tree is vigorous with a slightly open habit.

Yields are satisfactory and quite regular.

Produces good quality fruits, medium to large size fruits.

Fruits have a long storage life.

Matures late mid-season between February and March. Has a remarkable resistance to anthracnose and powdery mildew.
Tommy Atkins The fruits are oblong-oval; medium to large with a thick skin.

The colour ranges from orange-yellow to dark /light red.

The flowers are purplish in colour.

The flesh is good quality with medium fibre.

The flavour is poor if over irrigated.

Resistant to powdery mildew and anthracnose.

It is an early producer and fruits have a long shelf life.

Keitt The fruit is rounded oval and the colour ranges from yellow to light red when ripe.

The flower is lavender like and colour ranges from yellow to red.

The flesh is orange to yellow, fibreless except near the seed and is sweet flavoured. Tree is small to medium, and very productive.

For market acceptance, fruit requires post-harvest ethylene treatment to enhance color. Matures late.

Fairly resistant to anthracnose

Moderately susceptible to Powdery mildew

Highly susceptible not resistant to bacterial black spot

susceptible to sunburn

Kent The fruit is oval and the colour of the skin is greenish yellow.

The flower is greyish in colour.

The fruits are large especially from young trees.

The flesh is fibreless, sweet and has good flavour.

Fruits mature late, the last in the season.

It is highly susceptible to powdery mildew and black spot.

For market acceptance, fruit requires post-harvest ethylene treatment to enhance color.

Haden The tree grows large, spreads widely and produces medium size fruits which are juicy, moderate in fibre and very attractive in colour. This variety is susceptible to anthracnose, moderately susceptible to Powdery mildew. It is a medium early season variety harvested around January and February.
Peach The roundish/oblique medium-sized fruits are fibrous. The apex tip of shoot is broadly rounded with a depression on the ventral side and a slight beak. a pointed projection at the tip of a fruitThe thick tough skin is smooth with white spots and has an attractive yellow-orange colour. The flesh is apricot-yellow with a tender juicy texture. The eating quality is good; there is a sweet flavour and a very slight turpentine taste. Has a long shelf life. Fairly resistant to diseases

Suitable for higher elevations

Only suitable for the local market

Contains a high amount of fibre

Sensation The oval medium-sized fruit is deep yellow with a prominent dark-red to purple blush that covers most of its surface.

The skin is medium-thick, tough and separates easily from the flesh. The deep-yellow flesh is fibreless, firm and juicy. It is sweet, of a distinctive mild flavour and of good quality.

A heavy yielder but susceptibility to anthracnose

Kensington

The fruit is medium in size, almost round with a flattened base and a slight beak. a pointed projection at the tip of a fruitWhen ripe, the skin colour is yellow with a slightly orange/pink blush.

The skin is thick and adherent and the flesh yellow, sweet, soft and juicy with moderate to little fibre.

joining parts of plants together such that they will unite and continue their growth as one plantGood shelf life and excellent eating quality.

The trees are vigorous, spreading and produce consistently high yields.

Moderately susceptible not resistant to anthracnose

 

Ecological Requirements

Altitude

Mangoes do well in the lowland to upper midland zones, from an altitude 0-1500m asl.

Rainfall

Annual rainfall of 500-1000mm is sufficient for successful cultivation; however a higher production is achieved with higher rainfall around 1500mm.  Mangoes can also survive in areas with low rainfall of up to 300mm. A distinct dry or cold season stimulates flowering. Rain during flowering seriously reduces fruit set. After a mango tree is well established, it is drought tolerant, especially when the taproots have reached the water table.

Temperature

Mangoes perform best in the temperature range of 200C to 260C. Temperatures exceeding 400C may lead to sunburn of fruits and stunting of tree growth. Mangoes require a dry period at the time of flowering and sufficient heat during the time of fruit ripening. Growth slows down and fruit quality decreases with decreasing temperatures.

Depending on zones, Ngowe, Boribo, Apple and Batawi varieties do well in hot areas (0-700m asl) while Peach, Tommy Atkins Kent, Van Dyke Kensington, Haden, varieties are suited in warm areas (500-1500m asl).

Soils

It is well adapted to many types of soils, but prefers deep (at least 3m) soils that are fertile, loamy textured, and well drained for good growth. The water table should not be above 2.5-3m. A pH of 5.5 – 7.5 is desirable. Soils that are alkaline, rocky and very shallow should be avoided.

Land Preparation

The soil should be cultivated deeply. The field should be cleared off trees, bushes and weeds.

 

Propagation

Use only clean-grafted seedlings of recommended varieties obtained from registered fruit tree nurseries. Farmers can also plant seeds and graft latter or top work the already existing trees to introduce recommended varieties.

 

Raising seedlings in the nursery

  • Extract seeds from fresh ripe fruits by peeling the husks off.
  • Remove the hard woody endocarp before planting and examine the seed for disease or any damage caused by the mango weevil (Sternochetus spp); plant the inner seed only- germination is faster (2-4 weeks)
  • Plant the seed as soon as possible (before it dries out) in a nursery bed with the hump at soil level.
  • Transplant the seedlings into polythene bags (Size 18x23cm) when they are 10cm high.

Grafting

  • Make the graft union at 30cm above the ground.
  • Cleft grafting with scion of an improved variety is the most common method. Grafting is done before the mother tree flowers or at any time of the year as long as desired scions are available.
  • In moderate climate (not extremely hot), cover the scion and grafting union with transparent cap.
  • In a hot climate, take off all the leaf petioles very close to the scion’s bark and tie the grafting tape up to the top of the scion, leave only the tip bud open. This method prevents heat from accumulating under plastic cap recommended for moderate climates.
  • Shade the grafted plants and water frequently.
  • Grafted seedlings are ready for transplanting 4 months after grafting.

 

Orchard Establishment

Planting holes

  • Under dry condition: 90 x 90 x 60cm
  • Under wet conditions: 60 x 60 x 60cm

Spacing

The planting distance vary and depend on water availability, variety and management.

Common spacing:

  • For extensive management 12m x 12m.
  • For intensive management 8m x 10m.

Transplanting

  • Transplant before the beginning of the rains.
  • Separate top soil from sub soil.
  • Mix top soil with about 20 kg of well decomposed manure and 125g TSP or DAP before refilling into the planting hole, then add the sub soil.
  • Water the hole just before the planting to ensure contact of roots with moist soil.
  • Place the seedling in the hole, firm the soil around the plant, water well and mulch.

Under rain fed conditions, mango seedling should be planted preferably at the beginning of the rains. If there is sufficient irrigation, the planting is possible at any time of the year.

Fertilizer application

For higher yields, regular fertilizer application is necessary in the early years (up to 5 years). Application of the fertilizer should be gradually increased from 240g/tree (50kg/ha) of CAN during the first years up to 3kg/tree (600kg/ha) of CAN in the eighth year. Similarly, TSP application should be increased from 120g/tree (25kg/ha) in the first years, to 1.2kg/tree (250kg/ha) in the eighth year.

Application of farm yard manure

  • Apply 20kg per tree annually upto the first yield and 60kg in subsequent years.

The fertilizer and the manure should be well spread around the tree canopy at the beginning of rains.

Irrigation

Irrigation in the first years after planting promotes flushing (and suppresses flowering) and increase in tree size. When the tree is big enough to produce a substantial crop, irrigation is stopped or at least interrupted long enough to impose dormancy leading to flower initiation.

Weed Control

The areas under the tree canopy should be kept weed free.

Intercropping

During the first 5 years, intercropping is recommended in order to maximize income until an economical mango yield is achieved.

Mulching

In young plantation, mulching around the tree is recommended to suppress weeds and retain moisture.

Training and pruning

  1. Formative pruning

This is done when the young plants are 1m high.

  • Remove all the side shoots below the one metre height using secateurs or a sharp knife.
  • Do not allow any sprouts below the graft union.
  • Pinch off central leader (break over the top branch) to induce the formation of lateral shoots (side branches).
  • Allow 3-5 side branches to develop.
  • Maintain 3-4 branches equally spaced around the single stem; prune off weak ones.
  • Force the shoots to grow in the desired direction by using sticks of timber or strings holding them away from the centre. This forms the scaffold branches (main branches) that are the supporting framework for the growing tree.
  • Ensure an open scaffold system of growth (open crown).
  1. Pruning established trees
  • Remove dead, hanging and diseased branches. Open up canopy to facilitate          light penetration and reduce disease incidence.
  • Maintain scaffold branches
  1. Rejuvenation pruning

This is meant to bring mango trees in decline back to production. It is achieved by top working.

Year 1: Cap the seedling at 1m high in order to produce a spreading framework of branches.

Year 2: Leave 4-5 well spaced branches to be the future main ones. No further pruning is required in the following years except the removal of dead branches.

  1. Structural pruning

This should be done after fruit harvest. The canopy should be at least 1m above ground. Main branches should branch off the trunk at 1½m above the ground. Remove all dead branches and all sucker branches from main structural branches. Prune canopy to allow sunlight to penetrate and reach the ground under the tree.

Benefits from Pruning

  • Fruits are produced on outside edge of tree and they hold to maturity.
  • Open tree structure allows easy harvesting.
  • Tree produces larger fruits.
  • Allows inter-cropping.
  • Benefit from natural conditions of sun and air movement to prevent disease build up.
  • Control tree height and prevent excessive spreading of branches

To improve fruit production:

  • Keep the orchard clean.
  • Remove all over ripe fruits and all weeds from around the treeRemove one third of fruit after fruit set to avoid fruit abortion and allow expansion of the remaining fruits to an economic size.
  • Remove new branches that sprout on main structural branches.

Wind Break

Mangoes are susceptible to wind damage. Wind damages branches, causes flower shedding and fruit damage. Windbreaks such as  Grevillea or Neem trees should be planted where necessary.

Major Pests

Pests Symptoms Control
Fruit flies

(Ceratitis cosyra, C. rosa and C.capitata)

The flies are brightly coloured, usually with brown-yellow–black pattern. The wings are spotted or banded with yellow and brown margin.

The eggs are laid under the surface of the fruit skin. After hatching the maggots penetrate the flesh and destroy the fruits from inside, causing fruits to rot.

Infected parts of the fruit become soft and have a premature colouring.

Collect and destroy all fallen fruits by burying at least 50cm in the soil or burning. Alternatively put them in a drum of water and cover with a layer of oil to suffocate the pest

Harvest the fruits just before they ripen.

Heavy attacks may be treated with recommended bait sprays consisting of insecticide e.g. Decis, Marshal, Lebaycid mixed with sugar or molasses.

Mango weevil

(Sternochetus mangiferae)

The mango weevil is greyish brown in colour.

The female beetle lays eggs into young fruits, causing small dark marks.

The larva is white with a brown head, burrows through the flesh into the seeds, where it feeds until pupation, destroying the seed.

The adult emerges by tunneling through the flesh into open leaving a small hole on the fruit skin. This may lead to formation of a hard white area in the flesh or the fruit may fall prematurely or rot in storage.

Fallen fruits should be removed and destroyed.

Use insecticide when fruits are forming e.g.  Decis, Marshal.

Paint trunk with white paint mixed with insecticide)

Mango gallfly

(Procantarinia spp)

The mango gallfly is a very small insect that lays eggs in young leaves.

The larvae feed on the leaves.

Young leaves may be covered with galls. Heavy infestation may lead to premature leaf drop.

Parasitic wasps usually control mango gallfly and no control measures are needed.
Mango white scales

(Ferrisia virgatta)

The mango scales are brown with a round white covering. They infest young twigs, leaves and fruits.

The infested spots on the fruit turn yellow and become depressed, making the fruit less attractive.

Control with Decis mixed with white oil.
Green Shield Scale

(Pulvinaria psidii)

Small oval greenish.

Scales whose adults are brown with cotton wool egg.

Control with Decis mixed with white oil.
Red Banded Thrips (Selenothrips rubrocinctus) Leaves become dark stained and rusty in appearance with small shiny black excreta present. Use Recommended mitecides e.g. Kelthane, Omite, Ortus 5SC, Mitac

Major Diseases

Disease Symptoms Control
Powdery mildew

Oidium mangiferae

Caused by a fungus which infects only younger tender tissues. The entire flower panicle is coated with a white growth of fungus which later dries up.

Flowers are shed without forming fruits. Infected fruits turn brown, may crack and usually drop at pea size.

Typical white powdery patches are formed on young leaves which curl and deform.

Plant resistant varieties e.g. Tommy Atkins.

Spray at bud break using Sodium bicarbonate,  Cosavet DF,  Nimrod 25EC, Topsin M

Anthracnose (Collelotricum gloesporioides) The symptoms appear as small brown spots on the flower panicle. The spots enlarge and kill the entire panicle.

Young leaves are similarly affected but spots remain small and often the centre drops out.

Pin size black or brown spots develop on the young fruit. As the fruit ripens, black slightly sunken spots, often with a central pinkish area develop.

The disease is particularly important during post-harvest resulting in black rot of the flesh

Prune dead branches and twigs and remove them from the orchard.

Plant resistant varieties e.g. Tommy Atkins.

Use copper based fungicide. Apply the fungicides when the first panicles appear but before the flowers open.

Where feasible fruits should be stored at 10-120C.

Scab

Elsienoe mangifera

Bright coloured wart-like spots on leaves and stem and can cause serious losses in nurseries as seedlings blight. Use recommended fungicide e.g. Daconil, Dithane M45, Equation pro

 

Algae leaf spot Cephalenras mycidea Orange brown patches on surface of leaves. Use recommended fungicide e.g. Daconil, Dithane M45, Equation pro

Harvesting

  • Harvesting starts 3-4 years after transplan For distant export market the fruits should be harvested at mature green stage. Maturity is determined by distinct skin and flesh colour changes and an increase in sugar content.
  • Depending on varieties and environmental conditions it takes 90 to 160 days after flowering for mangoes to reach maturity.
  • A mature mango fruit has well developed shoulders (region around the fruit stem), or when cut open, 50% of the fruit has changed from greenish white tyellow-orange.

Mangoes taste best when they are ripe. Do not depend on the colour of the fruit to indicate ripeness. Different varieties of mangoes do not change skins colour no matter how ripe. Several methods exist for determining ripeness. However the characteristic of each mango variety should be taken into account. It is advisable to observe the ripening pattern for each variety.

Examples of ripeness testing methods Hold the mango in your hand gently, stem end up. Bring the mango up to your nose and smell the stem end. If it has a sweet aroma that does not smell alcoholic it’s ripe. If the mango has no smell, it is under ripe. If it smells alcoholic, it is overly ripe and is spoiling.

Squeeze the mango gently. If it  yields to pressure without feeling mushy its ripe. Look at the shape of the fruit around the stem. If it looks flat or hard, the mango is not yet ripe. If it is plump or rounded, the mango is ripe.

Harvesting

Fruits are harvested by hand. For tall varieties fruits can be harvested by using ladders or by climbing the tree. Picking pole with a basket attachment are also used. It is recommended that fruits should be clipped from the tree in such a way that approximately 3-4cm of the stalk is left on the fruit, which is later cut to 1cm during final packing.

Latex (a sticky secretion) oozing out of the cut stalk is sticky and if any adheres to the skin of fruit it stains and renders it unattractive. It also reduces the shelf life. To reduce effect of the latex flow immediately after cutting the stalk, drain the fruits over leaf ribs on the ground rather than washing them in water.

Yields 

The first yields are expected about 3-4 years after planting for grafted/budded mangoes seedlings. The orchard reaches full maturity within 6-8 years and yield increases gradually for 20 years.

Expected yields

Year         Yield (Fruits/year)
3 500
4 1000
5 5000
6 10,000
>7 15,000

A mature tree can yield 400-600 fruits/year. About 15 tons/ha can be obtained if regular and intensive orchard maintenance is provided. Alternate bearing is common in mangoes so yield will fluctuate from season to season.

Post harvest management

Wash fruits using hot water where possible at 550C for 5 minutes to destroy disease causing agents. Fruit damage occurs at high temperatures. The major post harvest diseases for mangoes are anthracnose and stem end rot.

The ideal post harvest storage temperature is 130C. When stored properly mangoes have a shelf life of 1 to 2 weeks.

Utilization

Mangoes are eaten fresh, canned or are processed. Sour, unripe mangoes are used in chutneys, pickles and preserves, as side dishes, or may be eaten raw with salt, chili, or soy sauce.  Ripe mangoes may be used to make juices, mango nectar, and as a flavoring and major ingredient in ice cream.

Marketing

Mangoes are grown both for export and local markets