Garcinia the 'cambodge tree' is a good-sized glabrous and evergreen tree belonging to the family Clusiaceae and presently known under the scientific name, Garcinia Cambogia (L.). It is commonly seen in the western ghats of Kerala, Karnataka, and in Sri Lanka. In Kerala the tree is seen in plenty in mid-Travencore tract and in Karnataka in Konkan tract. Garcinia shows wide variability in yield, growth habit, and fruit qualities. Both male and hermaphrodite trees are met with in the genus.

The tree is very much adapted to both hilltops and plain lands alike. But, its performance is best in riverbanks and valleys. It grows well in dry or occasionally water logged or flooded soils. Usually seedling takes 10-12 years to start bearing. The percentage of male trees in population varies from 50-60 per cent and this also creates much difficulty in the cultivation of the crop. Problems such as lack of high yielder, planting grafts prepared from elite mother trees can solve variability in population and occurrence of male trees.

The economic part of the plant is its mature fruit which are highly acidic. The rinds of the ripe fruit are processed and used as a condiment in fish and prawn preparations to impart flavour and taste and to improve the keeping quality. The extracts obtained from the mature fruit rind, Hydroxy Citric Acid, attracts foreign markets - thanks to its use in medicines controlling obesity. It is also one of the ingredients in many ayurvedic medicines.

Even though garcinia is one of the oldest tree spices of the State, only recently that it has attained international importance. Hence research work in the field of crop improvement and crop husbandry is very meagre. Most of the trees in the field are of seedling origin and hence they exhibit wide variability. Recently Kerala Agricultural University has identified a few promising types which are being multiplied for cultivation.

Use grafts prepared through Soft grafting/ side grafting or the healthy seedlings raised in the nursery, for cultivation. If seedlings are planted, 50-60 percent will be male, and hence planting of grafts are advocated as they ensure maternal characters and early bearing tendency.

Selection of mother trees: Mother trees which give steady annual yield, having a mean fruit weight of 200-275g, high acid content and low tannin content are located, Seeds are collected from freshly harvested and fully ripened fruits and washed in running water and spread in a thin layer under roof. By twentieth day, seeds will be ready for sowing. Seeds at the rate two per bag are sown in poly bags during the month of August-September. It takes five to seven months for the seed to start germination. Usually seeds start sprouting in the month of December and they come above the soil surface by February. In order to avoid delayed germination, simple seed treatment methods are employed.

Method 1: Processed seeds (after drying under shade) are given a mechanical treatment. Seed coat of such seeds are removed using a sharp knife without injuring the ivory coloured cotyledon. These ivory coloured cotyledons are sown afresh in poly bags at a depth of 2 inches and they start germinating in 20-25 days after sowing.

Method 2: Seeds, after removing the seed coat, are treated with gibberelic acid @ 250 ppm for six hours, and later they are soaked in Dithane M-45 @ 4g/I for two hours. They are sown in nursery bags and irrigated daily. Seeds germinate in 16-20 days time.

Method 3: After removing the seed coat, seeds treated with gibberelic acid @ 250 ppm for six hours, and later they are soaked in Dithane M-45 @ 4g/I for two hours. These seeds are then transferred to a white poly propylene cover of the size 20 cm x 25 cm along with 30-50 ml of filtered water. The poly bag along with the air inside is tied tightly using a rubber band. Such seeds germinate in 10-12 days after sowing. In a poly bag, about 500-750 seeds can be incubated at a time. Sprouted seeds are picked up and sown in the nursery bags kept under shade.

Raising seedlings: Seedlings can be kept under open condition or under shade. They are to be watered regularly on alternate days during summer months. Those seedlings, which are kept under shade, after 3-4 months, are placed under direct sun light to trigger growth. At this age, apply FYM @ 50g per bag. In six to seven months time, seedlings will be ready for planting.

Seedling usually takes 10-12 years for bearing. Fifty percent of the population will be male and unproductive. There will be variation in the inheritance of maternal characters in the progenies. For these reasons, grafts are preferred to seedlings. Grafts start bearing in three-four years time, true to type progenies are obtained, height of the tree can be controlled and more number of trees can be planted in a unit area. Two types of grafting methods are employed: soft-wood grafting and approach grafting.

Scions are selected only from specific elite trees showing regular bearing tendency, yielding large sized and quality fruits.

Collection of scions: Straight growing, healthy young shoots emerging from the primary branches with whorled leaf arrangement are selected. They are cut at a length of 6-10 cm length and stored in poly bags under humid condition. Leaves are partly removed and the cut end is shaped to a wedge of three-four cm long by giving slanting cuts on the two opposite sides.

Preparation of root stock: Stock plants having 3-4 mm stem thickness is ideal for grafting. Selected plants will be deheaded at two nodes below the terminal bud and all the leaves are partly removed. Grafting is done using scion and root stock of same thickness.

Grafting: The wedge of the scion is inserted into the cleft of the root stock and the graft joint is secured firmly by black polythene tape of 1.5-2 cm wide and 30 cm long.

Care In the nursery: Immediately after grafting they are kept either in mist house or covered with transparent poly-propylene cover and kept under shade. By the thirtieth day the grafts would have established and new leaves start emerging. The grafts are then removed from the mist house or the polythene cover and kept under shade. Grafts are to be watered daily using rose can or microsprinkler. Care should be taken to remove sprouts emerging from root stock at frequent intervals. Three months after grafting the plants will be ready for planting in the main field. just before planting in the main field the grafts are left under open condition for hardening.

Approach grafting: Here also stock plants having three-four mm thickness are preferred and they are brought to the place where the mother tree is located. Grafting is done as in other crops and they are kept intact for 45 days by which time union occurs. Graft is detached from the mother tree in three steps. The main disadvantage is that only a limited number of grafts can be produced in this method. Forty five days after grafting, they will be ready for transferring to the main nursery for hardening. Grafts are to be watered daily using rose can or micro-sprinkler. Care should be taken to remove sprouts emerging from rootstock at frequent intervals. Leaf folder pests are very common in the nursery. Spray Ekalux @ 2ml/L of water at monthly intervals.

The crop can be raised as a pure or as a perennial intercrop of coconut, arecanut etc. Pits of the size 75x75x75 cm in hard and laterite soils, 50x50x50 cm in sandy and alluvial soils, at a spacing of 4m x 4m for grafting and 7m x 7m for seedlings, are prepared. In hill slopes of 15% or more, for planting grafts rows are spaced at 5 to 5.5 m and 3.5m between trees in a row. For planting seedlings, rows are spread at 8 to 12 m apart and at 6 to 8 m for trees in row. Planting is generally done during July-October months. Under existing coconut plantations of 25 years and above, spacing shall be so adjusted that it should alternate with the palms in the rows. Under Kuttanad conditions, where bunds and channels alternate, planting can be done in between two palms. Planting pits are filled with top soil and two kg of compost or well decomposed cattle manure and Iog of sevin or lindane dust, to avoid white ants attack, before planting. The graft union shall remain just above the ground level. Plants are to be supported with bamboo split of 2.5' long. One month after planting the polythene tape around the graft union is gently removed.

Apply 10 kg of cattle manure or compost per seedling/graft during the first year. Increase the quantity gradually till a well grown tree of 15 years and above receives 50 kg of organic manure per year. Apply NPK mixture at the rate of 20:18:50 g/plant during the first year. This is doubled in the second year and gradually increased to 500:250: 1000 g/plant/year so as to obtain full dose at 15th year onwards.

Grafts will grow fast from second year onwards. Strong support of casuarina poles are to be given at this stage. By fifth year the tree will have 3 to 4m height. From third year onwards some of the fast growing branches are to be pruned so as to balance the weight. In the fifth year the height of the plant may be maintained at 3.5 to 4m and by seventh year at 4 to 4.5m.

Hard scales and beetles are the common pests infesting the crop. The hard scales desap the leaves and tender shoots. Both the beetles and grubs defoliate the crop inflicting heavy loss on yield. These can be controlled by spraying Rogor or Nuvacron @ 1.5 ml/l. Sooty mould is seen associated with the hard scales. Seedling blight in the nursery stage is very common and this can be controlled by spraying I% Bordeaux mixture or Dithane M 45 @ 4 g/l. Leaf folders are very common in the nursery. Spray Ekalux @ 2ml/lit at monthly intervals to control the pest.

Seed-grown plants start bearing generally at the age of 10-12 years. Grafts start bearing from the third year onwards and will attain the stage of full bearing at the age of 12 to 15 years. Flowering occurs in January-March and fruits mature in July. There are reports of off season bearers, which bear two times a year, ie., during january-july and September-February. Mature fruits which are orange yellow in colour, either drop from the tree or are harvested manually. The fruit rind is separated for processing immediately after harvest.

Separated fruit rind is first sun dried and then either smoked or oven dried. In order to increase the storage life and impart softness, the dried rind is mixed with common salt @ 150 g and coconut oil @ 50 ml per kg of dried rind