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 gummi-gutta (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 riped 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. |
Varieties |
| 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. |
Planting Materials |
| 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. |
Propagation by seedlings |
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 gibberlic 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. Rasising 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. |
Propagation by grafting |
| 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 over the 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. |
Soft wood 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 stern 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 coverd 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. |
Planting and Management of Plantations |
| 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 alluvia) 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 I Og 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. |
Manuring |
| 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. |
Purning |
| Grafts will grow fast from second year onwards. Strong
support of casuarina poles are to be give 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. |
Pests and Diseases |
| 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. |
Harvesting |
| 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.
Flow'ering 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. |
Processing |
| 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. |