Authors: Amrendra Kumar, RK Patel. SD Pandey, Kuldeep Srivastava, SK Purbey and Vishal Nath
National Research Centre on Litchi, Muzaffapur, Bihar
Litchi the queen of fruits is native of Southern China. It is widely adapted to the warm subtropics, cropping best in the regions with brief cool dry frost-free winters and long hot summers with high rainfall and humidity. Litchi has spread to most tropical and subtropical world and commercial industries has been developed in several countries like, Taiwan, Thailand, India, South Africa, Australia etc.
Composition and uses
Litchi is a delicious fruit of excellent quality. The fruit has high sugar content which varies between 10 to 14 per cent due to cultivar and climatic condition. Besides sugars litchi contains 0.7 per cent protein; 0.3 per cent fat; 0.7 per cent minerals (particularly calcium and phosphorus) and vitamin C (64 mg/ 100 g pulp) A, B1 and B2.
Litchi makes an excellent canned fruit. A highly flavoured squash is also prepared from inferior fruits, which is liked by many during summer months. Various other products, such as pickles, preserve, nuts and wine can be prepared from litchi. Dried litchi nut is very popular among the Chinese.
Origin and distribution
The litchi is indigenous to the southern part of China. It spread further to West Indies, South Africa, Hawaii Islands, Florida, Vietnam, Indonesia, India, southern Japan, Formosa, Australia, Newzealand, Brazil, etc.
Litchi reached India through Burma at the end of the 17th century and its cultivation is now gaining popularity at a very fast rate. In India, the bulk of the litchi growing area lies in Bihar, other areas lie on the submountane tracts of Uttar Pradesh, West Bengal, Punjab, Assam, Tripura and Orissa.
Species and cultivars
Species:
Litchi belongs to the family Sapindaceae and sub family Nephelaceae which has about 125 genera and more than 1,000 species. The genus Litchi has two species, Litchi philippinensis and Litchi chinensis; Litchi philippinensis is a wild type, mostly used as rootstock. The other members of the subfamily, longon (Euphoria longana) and Rambutan (Nephelium lappaceium) are also important tropical fruits.
Cultivars
There are a large number of litchi cultivars grown all over India, but the difficulty is that the same cultivar may be known under different names in different places. The important cultivars for different litchi growing states in India are-
Bihar : Shahi, China, Purbi, Rose-scented, Kasba
Uttar Pradesh : Dehradun, Muzaffarpur, Saharanpur
Punjab and Haryana : Saharanpur, Dehradun, Culcutta, Muzaffarpur,
Seedless Late, Rose-scented
West Bengal : Bombai, China, Bedana, Elachi
Distinguished characteristic of the important cultivars
Bombai: Trees are vigorous and attain an average height of 6 to 7 m and spread of 7 to 8 m, the fruits ripen in the first of second week of May. Fruits are heart shaped and on ripen the tubercles turn carmine- red and interspaces uranium green in colour.
Muzaffarpur: A heavy bearing cultivar. The fruits are deep orange to pink and are less prone to splitting. In Eastern India, the fruits mature in the first week of May while it ripens in the middle of June in North India.
Dehra Dun: Trees are medium in vigor, attaining a height of 5 m and spread of 7m. it is a medium to highly yielding cultivar. Fruits are obliquely heart shaped to conical, bright rose- pink in colour.
Shahi: This is one of the leading cultivar in Muzaffarpur area of Bihar. Fruits are oval and oblong conical in shape which matures in the third week of May. At maturity, the tubercles become flat and crimson-red in colour. The bearing is heavy and the fruits are generally large (20 â€" 26 g) with a mid rosy fragrance.
China: The trees are semi-dwarf and alternate bearer. The fruits ripen from the third week of May and the average yield varies between 80 to 100 kg per tree. Fruits medium to large, mostly globose, a mixture of nasturtium-red and marigold-orange in colour.
Kasba: Fruits medium to large, ripen in the first week of June. The fruits are heart-shaped, reddish background and red tubercles. The average yield varies between 80 to 100 kg per tree.
Rose-scented: The cultivar is so called due to presence of delicate rose flavour in the aril. Fruits medium to large in size which ripen from the second week of June. Fruits are mostly oval or oblong conical in shape and deep rose-pink in colour. The average yield varies between 50 to 60 kg per tree.
Elachi: The trees are moderately vigorous, attaining an average height of 5 to 6m and spread of 6 to 7 m. The average yield varies between 50 to 60 kg per tree.
Purbi: Fruits are medium to large which ripen at the end of May or first week of June; conical to oblong- conical in shape. The colour of the tubercles is red on pinkish brown background. The average yield varies between 90 and 100 kg per tree.
Soil and climate
Soil
Litchi can grow in a variety of soil provided they are well drained. The ideal soil for litchi cultivation is deep well- drained loam soil rich in organic matter. The water table should be at least 1.25 m deep. It can’t stand water-logging for long. Litchi prefers slightly acidic to neutral soil. The trees grow best in a pH range of 5.0 to 5.5. The roots of litchi trees are found to have a symbiotic association with mycorrhizal fungi which improves the nutrient uptake by roots. Before planting, it is worthwhile to inoculate the soil in pit by mixing some soil from the root zone of litchi plantations.
Climate
Litchi prefers moist subtropical climate. Winter frost and dry heat in summer considerably damage the growth of the plants and fruits. Although it can grow up to an altitude of 800 m above the sea level, the best growth and yield was, however, found at lower elevations. Seasonal variation in temperature is necessary for proper fruiting. The temperature should not go beyond 400C in summer and below the freezing point in winter. Good rain or adequate supply of irrigation water is essential for litchi cultivation. A constant rainfall at the time of flowering, however, interferes with pollination and affects fruit set.
Propagation
Litchi is mainly propagated by air layering. It is the most widely accepted method for propagation of litchi on a commercial scale. Upright branches of 2-3 cm diameter and 30 to 60 cm long from well developed trees, free from pests and diseases, are suitable for layering. Treatment with IBA at 500ppm in lanolin on the upper end of the ring improved root formation. For enclosing the cut end, rooting media consisting of equal part of vermiculite, vermi-compost and coco-peat in polyethylene film is used for successful rooting in litchi layers. To raise the quality planting material of litchi, air layering should be done on selected mother plants.
Cultivation
Windbreak: The growth of the litchi plants are adversely affected due to hot wind in summer and cold waves in winter. It is advisable to plant suitable windbreak trees around the boundary of litchi plantations. Tall- growing tree, such as, seedling mango, eucalyptus, jamun, etc., may be planted as windbreak.
Planting: The litchi trees are planted according to square system of planting at 8-10m apart in both row to row and plant to plant. Before planting, pits of 1m x 1m x 1m should be dug out at the desired point and allowed to remain open for a few days. The pit should be filled with top soil mixed with 20 to 25 kg of well rotten FYM, 2kg of bone meal and 300g of Mureate of Potash. The pits are then watered to settle down. Planting should be done at the centre of the pit with the help of a planting board. Litchi is normally planted just after the monsoon in August- September which, however may be extended up to November in Punjab.
Care of young plants: To protect the young plants from hot and desiccating winds, a row of daincha (Sesbania sp.) should be grown around the basin early in the spring. Fifty grams of DAP should be applied a weeks after planting and every two months thereafter, which will help the young plants to make quick and vigorous growth.
Irrigation: Frequent irrigation is necessary during the early plant growth, irrigation should be done twice a week during dry and hot months for young plants and once a week for plants older than 4 years in age. Established orchards should be irrigated frequently during the fruiting period to ensure better performance of the tree. The orchard should also be irrigated after the application of fertilizers.
Manuring and fertilization: The nutrient requirement of litchi is very high. The following fertilizer schedule is suggested for cultivation of litchi.
| Manure/ fertilizer | Quantity (kg) per tree | ||
| Planting year | Annual increase | For mature tree (12 years and above) | |
| Compost | 20- 30 | 4.0 | 60-80.0 |
| Non-edible oil cake | 1- 2 | 0.2 | 4.0 |
| Urea | - | 0.2 | 2.0 |
| Di Ammonium Phosphate | 0.1 | 0.1 | 1.5 |
| Potassium sulphate | 0.1 | 0.1 | 1.2 |
| Lime in acidic soil | 1.0 | 0.3 | 4.0 |
The farmyard manure, super phosphate and murate of potash should be applied in autumn. Nitrogenous fertilizers should be divided into two - three equal parts and applied once in mid February and again after harvest of fruit. The zinc deficiency in litchi may be corrected by basal application of zinc sulphate 50g per plant or spraying of 0.2% zinc sulphate in the month of December. To over come the deficiency of boron applies 50-60 g boric acid in month of June or with fertilizer application.
Training and pruning
In litchi pruning is not an essential operation. In the beginning training of the tree is necessary to give a definite shape but generally no pruning is required, only the diseased and dried portions of the branches should be pruned. While harvesting litchi, a portion of the twig is also cut off along with the fruits, so a light pruning is done during harvesting. The removal of the ends of the fruiting branches promotes new shoots and also flowering next year.
Intercropping
In the early stage of establishment of litchi orchards, the inter-space can be economically utilize by growing suitable intercrops. In the crop combinations involving short duration fruit crops, vegetables and leguminous crops like pineapple, peas, cowpea, gram, beans are considered as safe intercrops. However when the trees are full grown, intercropping is not feasible and hence should not be grown at the cost of litchi plants. These should be manured separately and protected from the attack of pest and diseases.
Use of PGR and chemicals
Litchi trees come to bearing at the age of 3-4 years with proper care and management while the seedlings take 8 to10 years to flower. During initial years of 4-9 years, litchi plants exhibited erratic bearing. The flowering starts from later part of January to March depending upon the altitudinal and location specific variations under north Indian situation. Fruit starts ripening in April and May. In litchi, the inflorescence is a much branched panicle normally arising terminally from the previous seasons growth. Panicle may be pure as well as mixed. The different litchi cultivars show variations in their flowering and bearing habits and may accordingly be classified as regular, irregular, shy bearing etc. So, for effective pollination and fruit- set of litchi, planting of several cultivars in as orchard is suggested. The flowers are mainly staminate, hermaphrodite and pseudo-hermaphrodite. The first flowers to open are males, followed by hermaphrodites functioning as females and pseudo-hermaphrodites functioning as males. It was observed that if new flushes appear in autumn due to late rain, these shoots usually fail to bear flowers. Treatments with auxins and some other chemicals were found effective in inducing flowering. Three to four spraying with Ethrel @ 150 ppm during October to December or two spray of Ethrel @ 400 ppm in the month of November-December or 2-4 mm wide girdling of primary branches in the month of last week of August to 2nd week of September is found effective to promote flowering in junior bearing litchi plants.
Provision of pollinators
Litchi is generally a cross pollinated crop and pollination is mainly done by insects, such as honeybees, flies, ants and wasps. About 20-25 boxes/ha of honey bees are sufficient to ensure the proper pollination and fruit set in litchi. Mostly bees are visiting on flower for collection of nectar during morning hours (6-11 AM). Though, litchi plants flower profusely but only 1 to 2.5 per cent of the total flowers set fruits. This may be due to lack of fertilization or embryo abortion or hormonal imbalance.
Fruit growth and development
Fruit growth: There are two distinct phases of fruit growth in litchi. During the first phase, there is absolutely no growth of flesh while seeds develop at a high rate and during the second phase the rate of flesh growth overtakes that of seed growth, although seed growth continues simultaneously for some period of the second phase. The total soluble solid and total sugar content of fruits increase markedly at the later part of the second phase of fruit growth.
Fruit drop: The fruit drop occurs mostly just after fruit set and continues till maturity. The percentage of drop varies with the cultivars and climatic conditions prevailing at the time. Among the many contributory factors, the endogenous hormonal level may be responsible to some extent. Exogenous application of NAA (20 mg/l) or 0.5 to 1.0 per cent of ZnSO4 mixed with hydrated lime (2:1); 2 to 3 times at weekly interval considerably reduces fruit drop of litchi. Proper maintaining of soil moisture during fruit growth helps in reducing the fruit drop.
Insect-pests
Litchi fruit borer
Litchi is a perennial fruit tree and therefore, needs constant vigil and care throughout the year for economic yield. Apart from integrated plant nutrient supply and irrigation, timely action for checking the pests build up and their control before irreparable damage is essential. The management involves general care and timely management of orchard, development of pests’ escape, avoidance and resistance mechanisms in plants and of course, the biological and chemical control of pests up to threshold level.
• Trichogramma @ 50,000 eggs / ha and application of Nimbicidine 0.5%, Cypermethrin 25 EC @0.005 % and and Nuvan 100 EC @ 0.05% combinations proved to be best in minimizing the damage by fruit borer when sprayed twice at 7 days interval at fruit set (lentil stage) and at colour development stage.
• The combination Tricho chards, Nimbicidine and Kamdhenu Keet Niyantrak have also proved effective in minimizing the fruit borer at harvest and early stage also.
• Spraying of Diflubenzuron 25 WP @ 2 g/l during fruit development stage in April and May months. Last spray should be done at 15 days before anticipated fruit harvest.
Litchi mite
The erinose mite (Aceria litchi Keifer) is undoubtedly the most universal serious pest. The incidence of erineum mite is seen during March which remain active up to June-July on litchi trees. Occurrences coincide with period of new flush emergence and in severe cases entire tree can be affected. The small tiny nymph and adults stick to under surface of leaf, shoots and panicle and suck the cell sap. Consequently, the young leaf turns yellow to grayish-yellow, along with velvety growth on the under surface which subsequently turns brown. The affected mature leaf develops continuous to scattered brown patches with curling, twisting and leathery structure and fall prematurely.
• Clean cultivation
• Timely removal of affected twigs and its burning in the month of June (just after the harvest), September and January, prior to flushing and flower bud differentiation followed by 2 sprays of Dicofol 17.8 EC @ 3 ml/l or Propargite 57 EC @ 2.5 ml/l twice at 7 days interval in September/ October (on new shoots) and in February (before panicle emergence).
Bark eating caterpillar (Inderbela spp)
The caterpillar of Inderbela bores inside the trunk or main stem. The caterpillar is nocturnal in habit. During night they came out and feed on the bark of the stem. Larvae are protected by the large silken webs. The branch ceases the growth stem becomes weak and may ultimately fall on the ground. The presence of insects can be known by seeing excreta and silky web on the crotches and branches.
• The infested plant parts needs to be cleaned and insert the cotton wool soaked in kerosine oil or nuvacron or formalin in the hole with help of bicycle spoke and plugged with moist mud of fresh cow dung.
Leaf miner
• Timely removal of affected twigs/ leaves
• Two sprays of Dimethoate 30 EC @ 1.5 ml/l or Imidacloprid 17.8 SL @ 0.5 ml/l at 15 days interval during new flush significantly reduced the damage.
Litchi bug and Mealy bug
• Collect the insects and destroy them
• These insects can be effectively managed by two spraying of Dimethoate 30 EC @ 1.5 ml/l at 15 days interval during their incidence.
Leaf cutting weevil
• Deep ploughing during summer is beneficial in reducing the insect population.
• Shake the trees, collect insects and destroy them.
• Two spraying of Buprofezin 25 EC @ 1 ml/l or Dimethoate 30 EC @1.5 ml/l at 7-10 days interval during their incidence.
About Author / Additional Info: