Introduction
Jack is a tropical fruit species found in tropical, high rainfall, coastal and humid areas of the world. It belongs to family Moraceae. Scientifically Artocarpus heterophyllies, it is the favorite fruit of many owing to its sweetness. The jackfruit tree is widely cultivated in tropical regions of India, Bangladesh, Nepal, Sri Lanka, Vietnam, Thailand, Malaysia, Indonesia, and the Philippines. Jackfruit is also found across Africa, e.g., in Cameroon, Uganda, Tanzania, and Mauritius, as well as throughout Brazil and Caribbean nations such as Jamaica. However, India is considered to be the native of jack fruit.
In our country, the trees are found distributed in southern states like Kerala, Tamil Nadu, Karnataka, Goa, coastal Maharashtra and other states like, Assam, Bihar, Tripura, Uttar Pradesh and foothills of Himalayas. The name originated from its Malayalam name Chakka. It is also called kathhal (hindi and urdu), pala (Tamil), halasina hannu (kannada) panasa pandu (Telegu) and phanos (marathi and Konkani). The fleshy carpel which is botanically the perianth is the edible portion.
Apart from its use as a table fruit, jack is a popular fruit for preparation of pickles, chips, jack leather and papad. The fruit has got good potential for value addition into several products like squash, jam, candy, halwa etc. The ripe bulbs can be preserved for one year in sugar syrup or in the form of sweetened pulp. The unripe mature bulbs can be blanched and dehydrated for further use through out the year. Seed is a rich source of starch and a delicacy during season. The timber is highly valued for its strength and sought for construction and furniture. The dried leaves are stitched to make disposable plates.
Nutritional and medicinal properties of jack fruit
Jack fruit is rich in several nutrients (Table 1). It has acted as source of complete nutrition to the consumers. The fruit is equivalent to Avocado and olive in terms of the healthier mix of nutrients for human dietary needs, almost having the exact nutrient equivalents of mother’s milk. It is rich in vitamin B and C, Potassium, calcium, iron, proteins and high level of carbohydrates, affordable and readily available supplement to our staple food.
Its seeds are rich in proteins and can be relished as a nutritious nut. The fruit is also the source of chemical “Jacalin” useful in preventing colon cancer, AIDS etc.,
Health benefits of Jackfruit
- Strengthen Immune System
Jackfruit is an excellent source of vitamin C, which helps to protect against viral and bacterial infections. Vitamin C helps to strengthen the immune system function by supporting the white blood cells function. One cup of jackfruit can supply the body with a very good amount of this powerful antioxidant. - Protect against Cancer
In addition to containing vitamin C, jackfruit is also rich in phyto-nutrients such as lignants, lisoflavones and saopnin which have anti cancer and anti aging properties. These phyto-nutrients may help eliminate cancer causing free radicals from the body and slow the degeneration of cells that can lead to degenerative diseases - Aids in healthy digestion
Jackfruit is also known to contain anti ulcer properties which help cure ulcers and digestive disorders. In addition, the presence of high fiber in the jackfruit prevents constipation and helps in smooth bowel movements. These fibers also offer protection to mucous membrane by driving away the carcinogenic chemicals from the large intestine. - Maintain a healthy eye and skin
Jackfruit contains vitamin A, a powerful nutrient which is known to maintain a healthy eye and skin. It also helps prevent vision related problems such as macular degeneration and night blindness - Boost Energy
Jackfruit is considered as an energy generating fruit due to the presence of simple sugars like fructose and sucrose which give you an almost immediate energy boost. Although Jackfruit is an energy rich fruit it contains no saturated fatty oil and cholesterol making it a healthy fruit to savour. - Lower high blood pressure
Potassium contained in Jackfruit has been found to be helpful in the lowering of blood pressure and thus reducing the risk of heart attack as well as strokes. - Control Asthma
The root of jackfruit has been found to help those who suffer from asthma. Extract of boiled jackfruit root has been found to control asthma - Strengthen the Bone
Jackfruit is rich in magnesium a nutrient which is important in the absorption of calcium and works with calcium to help strengthen the bone and prevent bone related disorders such as osteoporosis - Prevent Anemia
Jackfruit also contains iron which helps to prevent anaemia and also helps in proper blood circulation in our body - Maintain a healthy Thyroid
Jackfruit is loaded with Copper, an important mineral, which plays a key role in the thyroid metabolism, especially in hormone production and absorption.
Cultivation aspects of jack fruit
Climatic and soil requirements:
Jack grows well and gives good yield in warm humid climate of hill slopes and hot humid climate of plains. The crop grows successfully from sea level upto an elevation of 1200 M. at an optimum temperature range of 22-35o C. It cannot tolerate frost or drought. The yield and quality of fruits are medium under low humidity. The West coast plains with high humidity are found to be highly suitable. A deep rich alluvial or open textured loamy soil or red laterite soils with slightly acidic condition (pH 6.0 – 6.5) with good drainage is ideal for jack fruit , however, it can come up in variety of soils.
Propagation and planting
When propagated through seeds, jack exhibits a wide variation among its progenies. Hence vegetative propagation is recommended. Commercially inarching on 10 months old jack seedlings is done to produce vegetative progenies. The grafts come to bearing within 4 ½ -5 years when compared to seedlings which take 7-8 years normally.
Soft wood grafting (cleft method) on 2 months old seedlings with scion of 3-4 months old also was found to be successful (70 -80%). Since the viability of seeds is very low, seeds have to be sown immediately after extraction to raise rootstocks. Rudrakshi and A. hirsute are also used as rootstock.
Pits of size 1 cubic meter are dug at a spacing of 6-8 m and filled with top soil mixed with 10 kg FYM. The grafts are planted in the centre of the pits during June-September. Proper staking is required to avoid lodging and subsequent breakage at graft joint. Thatching or providing shade with coconut leaves and thorough mulching of basins after the cessation of monsoon season are essential to avoid mortality of grafts.
Training and manuring
Jack trees are trained to a single stem, early side branches should be removed so that a uniform smooth trunk develops for a height of 1.5 – 2 M and then side branches should be permitted to arise. The flower buds appear on trunk which should be kept free of vegetative growth. The nutrients should be applied as detailed in Table 2.
Table 2. Requirement of manures and fertilizers for jack fruit
Manure/Nutrients | 1 year after planting(Kg/plant) | Annual increase(Kg/plant) | 5th year onwards (Kg/plant) |
FYM | 10 kg | 10 kg | 50 kg |
N | 0.150 | 0.150 | 0.750 |
P | 0.080 | 0.080 | 0.400 |
K | 0.100 | 0.100 | 0.500 |
The fertilizers are applied during rainy season. If irrigation is available they can be split into two doses and applied twice in a year ie during June –July and September – October. The manures and fertilizers can be applied in a circular trench taken 50-60 cm away from the trunk.
Irrigation
Though jack is cultivated under rainfed conditions, it is very sensitive to drought. Hence irrigation should be done depending on the type of soil, season etc. so that, there should not be any moisture stress especially during flowering and fruit set. Similarly too much of soil moisture will affect the quality of fruit. The carpels will develop an insipid taste when there is excess soil moisture.
Intercultivation
During the pre-bearing age pulses can be raised as intercrop and dried leaves can be spread below the trees to serve as a mulch for moisture conservation. As the trunk increases in size, the active buds of female inflorescence develop from the trunk as well as from main scaffold branches, this type of bearing habit is called ‘cauliflorus’. These fruit buds should be protected from any possible damage by rubbing of body of the stray cattle such as buffaloes through spreading dried thorny bushes. This is very essential especially when there is no proper fence in the fields.
Harvest and yield
Normally jack starts producing fruits from 7th – 8th year onwards. Grafted plants can start yield from 4th to 5th year itself. In Singapore jack, even seedlings start bearing from 3rd year. Normally the fruits will be available from March to June. In higher elevation harvest extends upto September. Even in plains certain genotypes bear an off season crop during October – December. The yield ranges from 20 to 100 fruits / tree. The fruit weight varies from 10 to 30 kg.