Tamarind is a multipurpose tropical fruit tree used primarily for its fruits, which are eaten fresh or processed, used as a seasoning or spice, or the fruits and seeds are processed for non-food uses. The species has a wide geographical distribution in the subtropics and semiarid tropics and is cultivated in numerous regions. The total area under Tamarind in Andhra Pradesh is about 6,099 hectares with estimated annual production of 46,962 tons.
Scientific name-Tamarindus indica.
Soil and Climate requirement for Tamarind-
The tamarind tree can grow in a wide range of soils and have no specific soil requirement. With little or no cultivation it can flourish in poor soils and on rocky terrain. It tolerates sodic and saline soils where it grows in ravines and on degraded land. Tamarind is adapted to a wide range of ecological conditions, reflecting its wide geographical distribution in the sub and semi-arid tropics. The maximum annual rainfall which tamarind can tolerate is up to 4000 mm, provided that the soil is well drained. Tamarind grows under these conditions in the wet tropics but does not flower. In fact, dry weather is important for flower initiation and if heavy rains occur during flowering tamarind does not bear fruit.
Tamarind Varieties in India-
There are only few varieties of tamarind. Important varieties in India are-
A clonal selection from the gene bank, it is early variety yielding 263 kg pods/tree with a pulp content of 39 %. It can give 26 tonnes of pods/ha if transplanted at a spacing of 10 m x 10 m.
This is another local type providing very long pods, having sweet pulp.
Variety released from Marathwada Agricultural University. Pulp has acid sweet taste, 60% pulp. 8% tartaric acid in pulp.
Variety released from Marathwada Agricultural University. High yielding type with red pulp, regular bearer, 11.00% acidity.
Propagation and Planting of Tamarind-
Tamarind can be successfully propagated by root and stem cuttings or air and stem-layering or by budding and grafting. However, commonly practiced method is by wedge and approach grafting. Young plants should be planted at 10×10m or 9×9m spacing. Pits of 1×1×1 m should be dug in the month of May-June and filled with 15 kg FYM, 1 kg SSP and 100 g Furadon granules along with loose soil. The ideal time for planting is July to October while planting graft union should be at least 10–20cm above the ground level. Plants should be staked and shoots arising from rootstock should be removed promptly.
Tamarind tolerates well to drought conditions, mostly grown as a rainfed fruit crop, however, initial first 2 to 3 years assured irrigation is essential for the establishment. During summer irrigation should be at every 7–10 days interval.
Pruning and Training of Tamarind plants-
Initial training and pruning of young plants during the first years is essential for the development of well-formed trees. Tamarind is a compact tree and produces symmetrical branches. Young trees should be pruned to allow 3-5 well-spaced branches to develop into the main scaffold structure of the tree. Bearing trees require very little pruning other than maintenance pruning to remove dead, weak and diseased branches and water sprouts.
Tamarind allows intercropping with a variety of annual crops. Vegetables and legumes can be grown during the rainy season in the interspaces in the first three to six years to augment farm income and improve soil fertility.
Manures and Fertilizers for Tamarind cultivation-
The nutritional requirement of tamarind has not yet been studied and standardized recommendations are therefore not available. Trees are known to fruit well even without fertilizer application, due to their deep and extensive root system. Inorganic fertilizers are not normally applied to tamarind trees, but 5 kg of farmyard manure is applied to the planting hole at the time of planting. Every year thereafter 5 kg of farmyard manure and 5 kg of neem cake are applied per tree in the months of March and April.
Irrigation of Taramind Plants-
Irrigation is not normally practiced in tamarind cultivation, but promotes better growth during establishment and the early stages of growth, especially during the dry seasons. Where irrigation facilities are available watering should be done and repeated as the need arises in the early stages of growth. In later years as the deep tap root system develops, the need for watering becomes less. Flowering and fruiting is promoted by irrigation. In dry areas, the use of water harvesting techniques during the rainy season should be considered as it encourages subsequent growth and fruiting. Mulching during the dry season will also help to reduce water losses from evaporation. Mulches around the trees also help in weed control and water conservation.
Flowering and Fruit set-
In tamarind, terminal vegetative shoots which bear flowers only in the following flowering season are produced annually. Two types of terminal shoots have been observed, short ones with an erect habit and long ones with a drooping habit. It is reported that production of flowers varies considerably between selections in India. Those with longer vegetative terminal shoots produce more flowers. In general, flowering and fruiting of tamarind takes place in the dry season. An extended spell of dry weather may be essential for fruit development. The period from flowering to pod ripening is 8-10 months. Ripe fruits, however, may remain on the tree until the next flowering period. In most of the tamarind producing countries the fruits are harvested from February to March/April, but sometimes the harvesting period may extend to June. In India, fruits are harvested from April to May.
Pests of Tamarind and control-
1.Fruit Borer (Lasioderma serricorne, Virachola isocrates)
The larvae infest ripening pods on the tree and persists in the stored fruits, larvae feed internally on the pulp and seeds and makes unmarketable.
Destroy the infected fruits.
Foliar spray with polytrine @ 1ml or Endosulphan @ 2ml/L or Carbaryl @ 3g/L for 2-3 times at 10 days interval.
2.Mealy bug (Planococcus lilacinus)
The mealybug, is a leading pest of tamarind in India, causing leaf-fall and sometimes shedding of young fruits.
Foliar spray with chloropyriphos (0.02%) or imidacloprid (0.04%) or deltamethrin (0.15) or dichlorovos (0.05%) as prophylactic or on observing the infestation.
Diseases of Tamarind and control-
A mildew caused by oidium sp. is a common occurrence in nursery seedlings. The disease causes defoliation and early growth is severely retarded.
In order to have effective control foliar sprays of wettable sulphur @ 3g/L at 15 day intervals is the most economical method.
Dr.Y.S.R. Horticulture University, Andhra Pradesh.