Rambutan

Rambutan

 Introduction Family :Sapindacea

Rambutan is a crop best suited to the mid- country and low- country wet zone of Sri Lanka. Flowering is more seasonal, trees tend to flower in February/March and fruits mature in July/August. Sometimes depending on the weather conditions, a small harvest is gathered during December to February.

Nutritive value (Per 100 edible portion)

Water	-
Energy	64.0k cal
Protein	1.0 g
Fat	0.1 g
Carbohydrates	16.5g
Calcium	20.0mg
Phosphorus	15.0mg
Iron	1.9mg
Thiamine	10.0 g
Riboflavin	60.0 g
Vit.C	53.0 g

Source: Medical Research Institute

There is a high demand for the crop locally as the fruits are delicious and limited cultivation area. The crop has a good export potential too. Presently very limited amount is exported to France, Germany and UK. Peak harvest could obtain during the period of July- August but high price ranging from Rs. 2-7 can obtain for the variety Malwana. Off seasonal crop during December- February can get more price than the seasonal crop. Therefore the extent of the areas such as Badulla Dunhinda, Haldummulla, Passara etc. which bear fruits off seasonally could be expanded.

Presently, rambutan is successfully grown in the districts of Gampaha and Colombo. Potential areas for future expansion are Rathnapura,Galle, Matara, Badulla, Kegalle and Kanddy districts

Using quality planting material, correct management practices, minimizing postharvest losses and farmer awareness programs can enhance the productivity. Rambutan is a seasonal crop and there is no continuity supply for export market. Therefore to lengthen the fruit production period the research program will include the testing of recommended varieties, where off season fruit is observed specially in Badulla and Monaragala district.

Recommended Varieties
Malawian special, Malayan red, Malayan yellow

Variety	Characters
Malayan special	Fruit
	Orange red colour
	Round shape.
	Average weight 40 - 50 g.
	Average length 4.3 - 5.0 cm
	Diameter of the broader end - 3.5 - 4.0 cm
	Diameter of the narrower end - 3.0 - 3.5 cm
	Length of the outer coat fibres - 1.5 - 2.0 cm and those are arranged closely.
	Thickness of the flesh - 8 mm - 9 mm.
	Flesh is sweet and loosely attached to seed.
	Can keep up to 3 days without colour change.
	Seed
	2.0 - 2.5 cm long and 1 - 2 cm width.Thickness - 1.0 - 1.3 cm.
Malayan red	Fruit
	Ellipse shaped.
	Dark red coloured.
	Average weight 28 - 35 g.
	Average length 5.0 - 6.0 cm.
	Diameter of the broader end - 3.2 - 3.7 cm.
	Diameter of the narrower end - 2.8 - 3.4 cm.
	Length of the outer coat fibres - 1.0 - 1.5 cm and they are thinly arranged.
	Thickness of the flesh - 8 mm - 9 mm.
	Flesh is sweet and can loosely attached to the seed.
	Can keep up to 3 days without colour change.
	Seed
	2.5 - 3.0 cm long and 0.8 - 0.9 cm width.
Malayan yellow	Fruit,
	Yellow coloured.
	Elongated shaped.
	Average weight 30 - 38 g.
	Average length 4.5 - 5.0 cm.
	Diameter of the broader end - 3.2 - 3.8 cm.
	Diameter of the narrower end - 2.5 - 2.8 cm.
	Length of the outer coat fibres - 1.5 - 2.0 cm and they are thinly arranged.
	Thickness of the flesh - 6.0 mm - 7.0 mm.
	Flesh is sweet and loosely attached to the seed.
	Can keep only up to one day without colour change.
	Seed
	2.5 - 3.0 cm long and 1.3 - 1.6 cm width.
	Thickness 0.6 - 0.8 cm.

Field Establishment
Climatic and soil requirement
Suitable environmental conditions are;

• 27 ^oC - 30 ^oC temperature
• Elevation 1500 m - 2000 m.
• Soil should be 2.0 m - 3.0 m depth.
• Well drained soil with organic matter is preferred.
• Relative humidity should be about 75 % - 80 %.

Time of planting
Planting should be done with the onset of rains.

Planting materials
Most popular planting material is grafted plants. Layered plants are also used.
Seedlings are not recommended.

Method of producing grafted plants

• First plant seeds in polyethylene bags (20 cm x 30 cm).
• Use 30 cm height and about one year old seedlings for grafting.
• Get the scion from a selected mother plant.
• Stem diameter should be 17 - 18 mm.
• Wedge grafting and patch grafting are recommended.
• Grafted plants should be obtained from a reliable source.

Planting

• Planting holes should be 60 cm x 60 cm x 60 cm.
• Two weeks before planting add compost and surface soil.
• First add a coconut husk layer to the bottom of the pit.
• When grafted plants are planted establish a stick to protect the union.
• Supply shade.

Crop Management
Weed control
weeding manually 1 m radius circle from the plant, twice a year.

Fertilizer application (per plant)

Time of application	Muriate of potash g	Rock phosphate g	Urea g
Basel dressing	110	115	120
After 6 months	55	115	60
After one year	55	115	60
After two year	165	345	180
After three year	275	575	300
From the 4th year
apply once every six months time.

Irrigation
Irrigate during drought periods until the plant become 2 - 3 years old.

Insects and pests
Fruit borer Acrosircops crammella
Damage the stem end

Diseases
Powdery mildew
Appear as white colour on fruit. Later fruits wither, turn black and dropped prematurely.

Control
By spraying of sulphur - several times during .the early stage.

Pruning

• Cut the water shoots and dead twigs.
• rain the plant from young stage to get a well balanced canopy

Harvesting & Post-harvest Technology
Among the three recommended varieties the best variety is found to be the variety Malwana special and this is yielded about 100- 150 kg per tree (over 8 years). Hundred plants are needed to complete one hectare with the spacing of 10 m x 10 m. The plants are available at both Government and private sector nurseries.

Fruit set

• Seedling plants will take about 7 - 8 years to fruit.
• Grafted plants will take about 3 - 4 years to fruit.

Value Added Products
Canned fruit in syrup

Harvesting time
Mid country wet zone = July, September.
Under average climatic conditions, June - August.
Some climatic conditions, December - February.

Harvesting

• Harvest when the fruits are matured and colour change is complete.
• Harvest as branches.
• Yield;

o Well grown plant gives 500 - 1500 fruits/ year
o An average plant gives 200 - 500 fruits/ year.

Method of harvesting

• Harvest when the fruits are matured and colour change is complete.
• Harvest as branches.

Post harvest treatments

• Harvested fruits collect in to a container as bunches.
• Do not expose to sun.
• Remove damaged fruits.

Storage techniques

• In normal conditions, fruits can be kept about 3 - 4 days.
• Cold storage conditions are 18 0C.
• Enclose low density polyethylene bags that contain ventilated holes, before storing at low temperature.

Packaging
Use rigid ventilated coconut leaf baskets or rigid boxes.

Transporting

• Use ventilated Lorries.
• Do not use open Lorries.
• Protect from sun light and rain careful loading and unloading.

Economics & Marketing
Availability
May - August

Cultivation Extent and production of Rambutan 1997/98

Year	Extent (ha)	Production (mt)	National av.yield mt)
1995	720	5760	8
1996	780	6240	8
1997	835	6680	8
1998	864	6912	8
1999	896	7168	8

Source: Senses and statistic Department

Export market

• Select fruits contain;
• Similar sizes
• At least 75% of characteristic colour.
• Do not select;
• Damaged fruits
• Fruits with insects/pest or and diseases.
• Packaging.
• Use plastic or rigifoam crates to load fruits and put them to cardboard or woody boxes.
• Pack bunches that contains 2 - 3 fruits or individual fruits in crates.
• Make ventilation holes on the boxes.
• Weight of a box;
• If use bunches = 4 - 5 Kg
• If use single fruits = 2 Kg.

Source: Agri dept Sri Lanka.