🌸 Durian And Carambola
Durian And Carambola.
This lesson compiles the core production technology concepts in a structured, exam-focused format while preserving the original subject content.
VARIETIES, NUTRIENT AND WATER MANAGEMENT, SPECIAL
CULTURAL OPERATIONS, PHYSIOLOGICAL DISORDERS,
PESTS AND DISEASES, MANAGEMENT PRACTICES
DURIAN
[ _ Durio zibethinus _ Bombacaceae]
Native to Borneo, an Island in the Malaysian region. It is tall evergreen tree of humid
tropics with ovoid oblong fruits, each weighing 2-5 kg characterized by trough fibrous rind
covered with greenish, coarse, sharp, pointed, short spines. The edible portion inside the fruit is
buttery with yellowish while pulp with very strong odour. People have strong like or dislike for
this fruit. Many like it, because if its sweet, delicious and filling taste, while others dislike it for
its highly objectionable odour. The penetrating odour is comparable to that of rotten onion and is
unacceptable to many. The chemicals that are responsible for the flavour are hydrogen sulphide,
ethyl hydrosulphide and dialkyl polysulphide.
100 g of edible portion 28.8 g CHO
2.5 g protein
2.5 g fat
20 mg Ca
63 mg P
37 mg Vitamin C
Indonesia, Philippines, India, Thailand, Myanmar and South China.
The fruits are believed to have aphrodosiacal qualities. Root decoction is used to cure
fever and leaves for curing jaundice.
Cultivars :
Frog, Gibbon, Longstem, Deception. Cha-Nee, Golden Pillow are important varieties of
durian.
Climate and soil requirements :
Perform well in areas with high humidity and high temperature, frequent showers and
low wind velocity Annual Rainfall 200 cm, but heavy rains prior to flower initiation affect
normal flowering. The trees cannot tolerate temperature below 8°C. Deep fertile soil or clay
loam heavy good drainage and organic matter are the best suited. Salt in soil or water will result
in fruit drop.
Propagation and planting :
Vegetative propagation by patch budding on seedling rootstock is recommended.
Seeds should be sown immediately after extraction from fruit as they loose viability very
rapidly. Though propagation through cuttings is easy, not recommended as the adventitious root
system will be insufficient to bear such tall stem. Plants of atleast 2 cultivars have to be planted
for effect pollination. Spacing is 10-12 m.
Pruning :
The tree usually takes pyramidal shape by itself. However, after harvesting the tree can
be cleared off dried and old twigs.
Manuring :
It needs manuring at early stages of crop growth. Upto 7 years absorption of nutrients and
retention on the vegetative part is more –
20 kg Nitrogen, 5 kg Phosphorus and 10 kg K/ha Potassium can be applied during 3 [rd]
year and can be increased to 40 kg, 10 kg and 20 kg of NPK during 7 [th] year. Beyond 7 years.
Only very little quantity can be applied.
Plant protection :
Hawk moth is serious problem, larvae feed on leaves, soil incorporation of Lindane 1.3 D
and creation of light traps recommendation, harvest, yield and post harvest management.
Grafts produce crop in 4-5 years, seedlings take 10 years. Fruiting available 2 times /
year. Durian has cauliflorous flowering in older branches. Self incompatibility noticed in Durian.
Yield – 100 fruits/year. Harvesting done when the fruits are smooth, flat with far – apart spines.
Ripe fruits last for 4 days under refrigeration, while mature fruits can be stored upto 14
days at 10-15°C.
CARAMBOLA
Carambola is a warm tropical and subtropical fruit with five star shaped projections and
having juice with characteristic acidic taste. It is also known as five corner fruit or five edge
fruit. The juice content is about 60 – 70%. The acidity is mainly due to oxalic acid and malic
acid. One hundred gram of fruit contains 3.5 – 11.0 g sugar, 0.75 g protein, 560 IU of vitamin A.
The probable origin of carambols is Malaysia or Indonesia. Besides consumed as dessert fruit,
carambola can also be served as juice, jam, jelly and pickle. The star shaped cross section slices
of fruit can be used in fruit-salad and to decorate cakes. A close relative of carambola is Bilimbi
(Averrhoa bilimbi) which produces more acidic fruits.
Climatic and soil requirements:
Carambola loves a warm, humid condition with long hours of sunshine. Though it can be
grown in a wider range of soils viz., right from sand to heavy clay loam, it will be at its best on
well drained deep clay loam with a pH of 5.2 to 6.2.
CULTIVARS:
Golden Star:
Developed by Florida, Queensland, Singapore, Taiwan and Japan. The wing edges are
slightly rounded. Fruits are golden yellow, crisp each weighting 90m- 200 g.
B1:
Developed at Malaysia having lemon yellow fruit which are crisp each weighing 100-300
g. The edges are rounded.
B6:
Another variety developed at Malaysia with orange fruits. The edges are slightly
rounded.
Maha:
Commonly grown in Florida. Fruits pale lemon yellow each weighing 100-200g. Besides
this a number of varieties like Thai kinight, wheeler F wang Tung are grown in Florida.
In Australia a number of local selections like Jungle Gold. Chujuba, Giant Siam are being
cultivated.
Propagation and Planting:
Approach grafting, wedge grafting and airlayering of one year old terminal shoots
(treated with IBNA 10,000 ppm at the time of layering) are the common methods of vegetative
propagation recommended. The plants can be planted in pits of size 1 M x 1 M x 1 M dug at a
spacing of 8 M x 6 M.
Irrigation, pruning and manuring:
Caramnola is very sensitive to water stress. It demands very high quantity of water (2000
lit / week/tree/in maximum demanding months). Mulching the tree basin will jelp to prevent
moisture stress. In young trees 4-6 wide – crotch angled branches are allowed. Low hanging
criss – cross branches should be pruned one year after planting. Each tree is applied 40 g N, 10g
P and 70 g K in 4 equal splits during April, June, September and January. Every year it can be
increased in the same ratio to reach 600 g N, 120 g P and 1000 g K/ tree at 8 [th] year.
Plant protections:
Fruit borer can be controlled by spraying chlorpyriphos 1 ml/lit. To control fruit sucking
moth, enclosing the fruits with mesh less than 10 mm is recommended. Cercospora leaf spot can
be controlled by Indofil M. 45@ 2g/lit.
Flowering, harvest and yied:
In India flowering is seen in three flushes April – May, July – August and September –
October and fruits are harvested in July – September, November – December and January –
February. Grafted trees start bearing 3 year after planting. The yield ranges from 200 – 300 kg /
tree from 7-8 years onwards. Even at 21 [o] C, carambola fruits can be stored for two weeks.
Summary Cheat Sheet
| Topic | Key exam points |
|---|---|
| Crop profile | Both are niche tropical fruits with market potential in suitable zones. |
| Climate | High humidity and warm conditions are generally favorable. |
| Soil | Deep, fertile, well-drained soils improve long-term tree performance. |
| Management | Establishment quality, irrigation, and canopy care strongly affect output. |
| Exam focus | Comparative adaptation and basic orchard package are commonly tested. |
References
2 sources • [1] [2]
References
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