6. LYCHEE PRODUCTION IN CHINA

Xuming Huang ^[6]

1. INTRODUCTION

Lychee (Litchi chinesis Sonn.) originated in the northern tropical and southern sub-tropical regions of South China. Wild lychee trees can be found as one of the dominant tree species of tropical rainforests in southern provinces such as Hainan, Guangdong, Guangxi and Yunnan.

As the original home of lychee, China was the first country to cultivate the fruit. The recorded history of lychee cultivation in the country is more than 2,100 years. In 111 BC, during the Han Dynasty, the royal record described a trial of planting lychee trees in the palace on the order of Emperor Hanwu. However, the trial ended in failure as lychee could not survive the northern climate. The delicious but rare lychee fruit was also highly appreciated by the later emperors who sent express horsemen to the south in order to carry lychee to the palace. The earliest description of lychee cultivars appeared in The Lychee Register written by Cai Xiang during the Song Dynasty in 1059 AD, which described lychee cultivation and 32 cultivars in Fujian Province. Another version of The Lychee Register by Chen Ding in 1780 mentioned 43 cultivars grown in Fujian, Sichuan, Guangdong and Guangxi. The figure increased to 74 in Guangdong according to Wu Yingkui in his book “The Lychee Register in Linnan”. The most popular cultivars like ‘Nuomici’, ‘Feizixiao’, ‘Guiwei’, ‘Sanyuehong’, ‘Huaizhi’ and ‘Heiye’ were described in this book.

Figure 1. Lychee cultivation area in Guangdong Province

Lychee used to be cultivated by individual farmer households as a sideline for self-consumption and the local market before the 1980s, and the fruit rarely reached the markets of the northern provinces of China. From 1949 to 1982, the lychee cultivation area in Guangdong, the largest lychee producing province, increased very slowly from 4,800 to 26,933 hectares. The average annual production during these 34 years was only 40,000 tons. A sharp increase in lychee area and production occurred in the1980s and 1990s (Figure 1). The trend of lychee production in the whole country followed the same pattern. The sharp increase in the 1980s and 1990s was due to rural reform and the implementation of market economy in the country. The rural reform involved a household contract system that allows farmer households to manage a piece of land for certain crops. The farmers then found that planting lychee brought them better economic benefit than planting most other crops. This resulted in a surge in lychee production in South China. Meanwhile, the market demand has also greatly stimulated the development of the lychee industry in China. As in the case of Guangdong province, the sharp increase in lychee cultivation area did not slow down until the end of the 1990s.

Most of the lychee orchards established before 1990 in China were managed by smallholders. They managed lychee orchards on a small scale ranging from several trees to several hectares. However, since 1990, corporations with financial strength have been investing in the lychee industry. Larger orchards of several dozen to several hundred hectares have emerged.

2. PRESENT SITUATION OF LYCHEE CULTIVATION IN CHINA

In 1999, the total lychee cultivation area in over-all China exceeded 580,000 hectares with a production exceeding 1.26 million tons. Lychee production regions in China are distributed between 19°-24° N latitude covering the provinces of Guangdong, Guangxi, Fujian, Hainan, Yunnan and Guizhou, although there is some lychee grown further north (28-29° N latitude) in Yibin and Dukou counties of Sichuan Province. This is because of the special local geographical circumstances and micro-climate which is suitable for lychee. The lychee acreage and production of the major lychee producing provinces in 1998 and 1999 are shown in Table 1. Since a considerable acreage (35 percent in Guangdong) of lychee orchards has been added within the past five years, the production of lychee is expected to increase considerably as the trees in these newly established orchards enter bearing stage. Lychee production has become an important industry in South China. In Guangdong, lychee is now the biggest fruit industry in terms of cultivated area accounting for 32 percent of the total fruit cultivation area (946,527 hectares) in the province.

Table 1. The acreage and production of lychee in the mainland provinces of China in 1998 and 1999

The dominant commercial cultivars in China are listed in Table 2 in order of maturation season. In Guangdong and Guangxi, the major early-season cultivars include ‘Sanyuehong’, ‘Baila’, ‘Shuidong’, ‘Dazao’, ‘Heiye’ and ‘Feizixiao’, while ‘Guiwei’, ‘Nuomici’ and ‘Huazhi’ are among the major mid- to late-season cultivars. In Fujian, late maturing cultivars such as ‘Chenzhi’, ‘Lanzhu’ and ‘Yuanhong’ are widely planted. The cultivars in Hainan are mostly early maturing ones whose flower induction does not need a very chilly winter. ‘Nanmuye’ is a local late-season cultivar in Sichuan. Apart from the cultivars listed, some less dominant cultivars are also well-known and populous. These include ‘Qipitian’ (Guangdong), ‘Gualu’ (Guangdong), ‘Edanli’ (Guangdong, Hainan), ‘Jinfeng’ (Guangdong), ‘Shangshuhuai’ (Guangdong), and ‘Zhuangyuanhong’ (Guangxi). Some new elite cultivars have recently been bred. Examples are ‘Dongguan Seedless’ and ‘Hexiachuan’, which produce parthenocarpic or highly chicken-tongued fruit, and ‘Maguili’, which is extremely late maturing (late August) in Guangdong.

A lychee-related organization, “Guangdong Lychee Technical Association (GLTA)” composed of researchers, extension officials, growers and dealers, is functioning as an important source of information about lychee production. The Lychee Technical Communication released by GLTA enjoys wide popularity among lychee researchers, growers and dealers all over the lychee production regions in China.

3. PRODUCTION OF PLANTING MATERIALS

Planting materials of lychee are propagated either by air-layering or by grafting (budding). For producing air-layered planting materials, 2-3 year old healthy branches about 2 cm in diameter are preferable. A strip of bark 2-3 cm in width is removed from the branch 15 cm from the fork and all the cambium tissue within the barking zone is cinctured. Root promoting growth regulators such as Indole-3-butric acid (0.5 percent) are often used to treat the bark above the cincture before wrapping with root growth medium. Mud from fertile paddy field mixed with straw or with sawdust or coconut shell dust is the most common root growth medium. Air-layers are removed from the tree after 3-5 months, when 2-3 growths of new roots have occurred. The plants are trimmed to a good structure, most of the leaves are removed, the mud head is unwrapped and soaked in water and the plants kept under shade and high humidity to allow new root growth before nursery planting or field planting. Although air-layering can be done all year round in Guangdong, it is preferable to do it in spring and summer.

Table 2. Dominant lychee cultivars in China

For grafting and budding, seedlings are planted in advance. Seedlings of ‘Huaizhi’ are good rootstock for ‘Nuomici’, ‘Guiwei’, ‘Baila’ and ‘Baitangying’; while those of ‘Heiye’ and ‘Dazao’ are commonly used as the rootstocks of ‘Feizixiao’. The seeds should be collected from fully mature fruit. They are sowed in rows at a space of 20 cm x 10-13 cm and then covered with a 1.5-2 cm thick layer of soil. Scion budwoods are taken from 1 year old healthy twigs with strong buds of the required cultivars. It is preferable to do grafting or budding in late spring or early autumn, avoiding hot, chilly or rainy weather. The grafted trees will be ready for field planting 6 months after successful grafting, when their second flushes have matured.

4. ESTABLISHMENT OF ORCHARDS

For lychee orchards to be established on lowlands with high water table, the planting rows are built into high ridges (1 m in width and 30-40 cm in height), between which draining ditches are dug about 0.8-1.0 m in depth. This is important to prevent waterlogging.

Most lychee orchards in China are built on hillsides. Although it is recommended to build lychee orchards on land with slopes of less than 10°, orchards on slopes higher than 20° are frequently seen. Vegetation is cleared when preparing the sloping land. Precautionary measures are critically important to prevent soil erosion in South China where there is at lot of rainfall. The common anti-soil erosion measures include terrace construction and a drainage ditch system. An anti-flood ditch is dug across the hillside above the terraces and connected to a number of vertical rain-collecting ditches leading to the foot of the hill. Usually these are dug along the edge of the walkway. The terrace surfaces are built inclining slightly inwards with a ridge at the outer side and a drainage ditch at the inner side, which joins the vertical ditches.

Lychee can be planted in spring, summer and autumn. Most farmers in China prefer to plant in the warm and humid spring (March to May). Planting pits 80-100 cm in depth and width are usually dug 3-5 months before planting during the winter. They are filled with green manure, soil, animal manure, compost, and lime and/or lime super phosphate (0.5 kg/pit) after several weeks of sun-exposure.

There is no standard planting space for lychee orchards in China. Most lychee farmers prefer to plant at a closer space (2.5-3 m x 3.5-4 m) initially and thin the plants as their crowns expand and overlap to a permanent spacing of 6m m x 6 m or 300 trees/hectare. Intercrops such as beans, peanut, sweet potato, vegetables, pineapple and papaya are highly recommended and widely adopted in young orchards. There are some farmers who have successfully adopted a dwarf and dense planting system for cultivars like ‘Feizixiao’, with a density of about 1,500 trees/hectare. The success depends much upon intensive orchard management including heavy pruning each year, frequent fertilization and sufficient irrigation.

5. CARE AND MANAGEMENT OF ORCHARDS

Tree training and pruning

The young trees are usually topped at a height of 50-60 cm in order to allow 3-4 lateral shoots to develop into the main branches so that the canopy will form a semi-dome shape. The management of young trees aims at promoting tree growth and expanding the tree canopy. Shoot growth of young non-bearing lychee trees is fast and the shoot growth cycle is frequent (5-6 shoot growths per year). The principle of fertilization for young trees is correspondingly ‘light but frequent’, either as soil application or foliage spray. A combination of 25-30 g of compound fertilizer, 20-26 g of urea, 15-20 g of potassium chloride and 50-70 g lime super phosphate is recommended for each tree in each application. Foliage spray with 0.3-0.5 percent urea + 0.3-0.6 percent KH₂PO₄+0.05-0.1 percent boric acid + 0.1-0.6 percent ZnSO₄ is also effective in supplying relevant elements to the young trees. Organic liquid fertilizers such as manure maceration extract, peanut meal maceration extract and molasses from sugar cane refineries, have been widely used by lychee growers in China. In dry seasons, irrigation is needed to ensure shoot growth.

The bearing trees are pruned during autumn and winter. Autumn pruning is done after harvest and before autumn shoot growth to encourage vigorous shoot growth. The trees are pruned to allow good light penetration and good ventilation in the orchard. Winter pruning should be slight and is done before spring shoots or panicle emergence, removing the diseased or pest damaged and weak twigs and thinning out overlapping ones. Bearing trees are managed to acquire a balance between vegetative growth and reproductive growth. After harvesting, two autumn flushes are fostered to form strong fruiting shoots for the coming year.

Fertilization

Fertilizer is usually applied at three crucial stages.

• Fertilizer application prior to flowering facilitates flower development and improves setting. For production of 100 kg fruit, 1.5 kg urea, 0.5 kg KCl and 0.4 kg lime super phosphate are recommended at this stage.

• Fertilizer application after full bloom is to compensate the nutrient consumed during flowering and to improve setting and encourage fruit development. K is the major element supplied in this application. A recommended fertilization at this stage for production of 100 kg fruit is 0.5 kg urea + 0.5 kg lime super phosphate + 1.4 kg KCl. An alternative is foliage spraying of 0.4 percent urea + 0.3 percent KH₂PO₄ prior to or after anthesis.

• Fertilizer application prior to harvest is for the promotion of autumn shoot growth and tree vigour recovery. For production of 100 kg of fruit, a combination of 1.5 kg urea + 0.5 kg KCl + 0.4 kg lime super phosphate is recommended for this stage. However, more and more farmers prefer mix these chemical fertilizers with organic fertilizer, such as chicken manure and fermented peanut meal.

Fertilizer is applied directly to the root zone of large trees in ditches dug 30-40 cm deep and 20-30 cm wide at two sides of the tree below the edge of the tree crown.

Weeding

Weeding is done either manually or with herbicides. Forage culture and mulching in lychee orchards are nowadays highly recommended by researchers to keep biodiversity and soil moisture, increase organic matter and reduce extremes of soil temperature in dry seasons.

Flower promotion

In order to prevent the growth of winter shoots, which is negative to flower induction, irrigation is withheld after the second autumn shoots mature. Girdling for vegetative control is also done on vigorous trees at this stage. Growth retardants such as paclobutrazole, ethephon and daminozide are used to suppress or kill winter flush.

Facilitating pollination and improving setting

Bee colonies are placed in the orchards during the flowering period in order to facilitate pollination and setting. Cultivars like ‘Feizixiao’ produce excessively large panicles that consume excessive nutrient. Therefore, panicle pruning or flower thinning is necessary to increase fruit set in these cultivars. Growth regulators like auxins and gibberellins are often used by farmers to reduce fruit drop. Girdling, either closed or spiral, is also widely applied prior to setting for fruit retention.

Pest and disease management

Considerable production loss is caused by problems such as diseases, pests and physiological disorders. The most serious ones are as follows.

• Downy mildew: A fungal disease (Peronophythora litchii) that damages fruit, panicles and new shoots, causing panicle rot and withering and watery brown spots on fruit which later produce snowy mildew. The disease is severe after successive rainy and overcast days.

• Anthracnose: A fungal disease which causes brown spots and quality loss on fruit, browning on the leaf tip and edge and tree vigour decline.

• Fruit cracking: A physiological disorder. ‘Nuomici’ and ‘Guiwei’ fruits crack most severely among all the lychee cultivars. Lychee fruit cracking is caused by multiple factors including heavy rain after long term drought, dry and hot wind, pests and diseases. Deficiency of Ca intensifies cracking. Anti-cracking measures include balanced water supply, application of Ca fertilizer and control of pests and diseases.

• Lychee stink bugs: The insects attack new shoots, inflorescence and fruits by sucking the sap, causing withering of shoots and flower and fruit drop.

• Lychee stem-end borer: Lava of the insect bore into the fruits or new shoots, causing fruit drop, inflorescence and new shoot withering.

• Lychee gall mite: The insect attacks new shoots, panicles and young fruit. Curling of the leaves and dense fuzz on the surface of infested organs are the characteristic symptoms of its damage. Gall mite infested trees produce low yield and poor quality fruit.

Chemicals commonly used in controlling pests and diseases are listed in Table 3. In order to lessen the dependence upon chemical control, lychee farmers in China take every possible agricultural means to bring pests and diseases under control. A good example is orchard cleaning, which is usually done in the dry late autumn or winter season. It includes weeding the orchard, loosening and sun drying the soil, winter pruning, burning the weeds and pruned twigs, and soil application of lime. These can reduce the incidence of diseases and pests remarkably, especially the soil-borne ones. Another good example is bagging the fruit clusters, which effectively protects the fruit from most of the pests and diseases. Bagging also improves the skin colouration, increases fruit size and facilitates maturation.

Table 3. Chemicals commonly used to control diseases and pests in lychee in China

6. HARVESTING OF FRUITS AND YIELDS

Fruit colour is an important indicator of fruit maturity. During maturation, the peel undergoes colour changes from green to yellowish green and to bright red 7-10 days later. When the peel colour changes into dark red from bright red, the fruit is over-matured with reduced storability as well as sugar content. It is recommended to harvest the fruit when their peel is 80 percent fully red. At this stage of maturity, the fruit is of good quality. In China, lychee harvesting is done entirely by hand, preferably in fine or overcast days. Rainy days and mid-day blazing sun are undesirable for harvesting. Sorting and packing is also mostly done by hand under shade within the orchard immediately after harvest.

Lychee yields differs greatly among cultivars, tree ages and years. A 10-year-old tree of large-seeded cultivars can produce as high as 100 kg of fruit, while the figure is usually much smaller for shrivel-seeded cultivars. 1999 saw a record high lychee production of 793,200 tons from a harvested area of 155,300 hectares in Guangdong, with a unit production of 5.1 tons per hectare. However, in the off-year of 1998, 327,000 tons of lychee fruit were harvested from 110,670 hectares, unit production being only 2.953 tons per hectare.

7. MARKETING

More than 60 percent of lychee produced is consumed fresh, about 30 percent is used for producing lychee nuts (dried lychee), and a small portion (2,500 tons in 1999) are frozen, canned or fermented.

Although different lychee cultivars differ considerably in maturation season, the peak period of harvest of the dominant cultivars lasts for only about one and half months from late May to early July (Figure 3). Most of the fruit produced has to be marketed immediately after picking, with a small portion cold-stored for later marketing.

Post-harvest treatment and packaging differs according to the distance and time the transportation of fruit takes. For local markets, where transportation takes only a few hours to reach, the fruits are given no treatment and are usually packed in bamboo baskets or cardboard boxes. For long distance markets, where transportation takes more a dozen hours without cold chain, the fruit are commonly packed in plastic bags and foam boxes with added ice (about 1/3 of the fruit in volume). Cold chain plus fast transportation means have enabled lychee produced in China to reach international markets in fresh condition. However, lychee fruit turn brown and rot rapidly after harvest especially when taken out from low temperature. Post-harvest treatments like SO₂ fumigation and acid dip are adopted to prevent fruit browning and preserve the fruit colour. However, the fruit thus treated have a sulphur dioxide residue problem and the market of such treated fruit is shrinking.

Lychee growers and consumers are mediated by a large number of fruit dealers in China. Smallholders sell their fruit at local markets by themselves or to lychee dealers who purchase lychee from individual growers and then sell the fruit to wholesale markets, retail dealers or supermarkets. Most of the corporations who run large lychee orchards have their own fixed channels of marketing. Some of them also run cold storage plants. They also purchase fruit from smallholders when their market demands more than they produce. Some lychee orchard managers market their fruit by running orchard tours that attract city dwellers who prefer to buy fruit freshly picked from the trees.

Local government plays an important role in promoting the marketing of lychee fruit. A successful example is the local government of Gaozhou in western Guangdong, which boasts the title of “No.1 Municipality of Lychee in the World”. By improving local infrastructure, holding lychee news conferences, inviting fruit dealers to local lychee trade fairs, organizing lychee exhibitions in major cities, setting up a lychee website and making every effort to spread their lychee information, the Gaozhou government has made the municipality known nationwide for its lychee fruit. When lychee ripens, lychee dealers crowd to Gaozhou and distribute the fruit in thousands of lorries to every corner of the country. In 1999, 120,000 tons of lychee fruit was produced within the municipality and sold out, bringing a total income of 1.2 billion Yuan (US$ 144.6 million) for local lychee growers.

Figure 3. The maturation season of major lychee cultivars in China

The lychee price in China varies greatly as a function of demand and supply in the market. The earliest cultivars, like ‘Sanyuehong’, are of low quality, but enjoy a fairly good price (around US$ 2 per kg) as this cultivar has no rival in the market. The price drops down as the peak season comes. In the off-year of 1998, the best quality ‘Nuomici’ and ‘Guiwei’ fruit cost US$ 10-15 per kg, while in the bumper year of 1999, their price dropped to only about US$ 0.5 per kg during the peak season. 2000 was a fair year for the two cultivars, their price was US$ 2-3 per kg. However, on international markets, lychee fruit enjoy good prices. In 1999, the lychee price was US$ 6.2 per kg in Germany, US$ 6.0 in Singapore, US$ 6.4 in the UK, US$ 14.4 in the USA, Holland and France, and US$ 16.8 in Canada. The amount of lychee exported via the port of Guangdong was about 7,000 tons in 1999 and dropped to about 1,370 tons in 2000 (calculated according to Yangcheng Evening, August 27, 2000).

8. POTENTIAL FOR LYCHEE PRODUCTION DEVELOPMENT IN CHINA

Lychee production in China has undergone rapid development since the 1980s. In the past 3 years, the development has slowed down. However, as the recently established lychee orchards enter production, a further increase in lychee production is expected for the coming years. The present lychee production has saturated the lychee market in South China, but there is an unsaturated market in North China. Even in the bumper year of 1999, lychee only reached large and medium sized cities with convenient transportation in North China. To the majority of consumers remote from lychee production regions in China, lychee is still a rare and inaccessible fruit. Moreover, lychee is the most competitive fruit in China for the international market. As long as there is a great domestic potential and international market, there is great room for further development. In addition, China possesses the best climate for lychee, plenty of sloping land that can be constructed into lychee orchards, and an incomparable rich germplasm and labour resource. However, lychee production development in China is still strongly limited by several constraints.

9. CONSTRAINTS IN LYCHEE DEVELOPMENT

The constraints limiting lychee development in China are:

Short shelf-life, poor storability and short production season

The lychee production season is short, about one and half months from late May to early July. The large quantity of lychee produced within such a short time must be marketed immediately since the fruit turn brown and rot rapidly (within 3 days) after harvest under ambient temperature. Short shelf-life strongly limits the extension of the lychee market in terms of time and space and causes heavy loss when the produced fruit cannot be marketed immediately. Cold storage houses are thus constructed in some large lychee orchards in order to provide a temporary buffer between production and marketing. Although low temperature storage (3-5°C) plus fungicide treatment (500 ppm TBZ or 250-500 ppm Sportak) has been able to keep fruit in fresh condition for 30-40 days, the capacity of the presently available cold storage houses is far from enough for the large quantity of lychee fruit produced in such a short season. Moreover, the poor storability of lychee fruit casts a high risk for cold storage companies to store the fruit. Lychee fruit become even more vulnerable to browning and rotting when taken from low temperature to ambient temperature. Therefore, cold chain is important to market cold-stored fruit. Unfortunately, there is a serious shortage of cold chain for the huge domestic market in China. Part of the reason is the high cost of cold chain. A much cheaper alternative involving transportation of lychee fruit packed in heatproof foam boxes plus ice has recently been widely used. However, the fruit in this type of package experience gradual temperature rise and cannot endure for more than 2 days.

Absence of an efficient and nationwide marketing system

Because of the short shelf-life and short production season of lychee, an efficient marketing system is urgently needed to enable lychee fruit produced in large quantity within a short period to be marketed before they turn brown. Presently, large number of small fruit dealers are playing the major role in fruit marketing system, which usually involves local dealers who purchase lychee fruit from the growers, transporters, wholesaler at the destination, and retail sellers. Most of the dealers do not have the financial strength to invest transportation means of large volume, cold storage and cold chain. Their business is therefore limited to a small volume and to a small region. They are functioning in an unorganized manner with a low handling capacity, far below the demand of the ever-increasing lychee production in the country. In some lychee production regions such as Gaozhou, the local government has set up an efficient information system to attract wholesalers from all parts of the country and a sound marketing system is running involving only growers, wholesalers, retail sellers and consumers. However, such a system awaits further development so as to cover all the lychee production regions as well as the nationwide market in China.

Unorganized production by individual farmers

Most of the lychee orchards in China are managed by unorganized individual farmers or smallholders. This production system functioned well before the local market was saturated. With the rapid expansion of lychee production and the saturation of local markets, its disadvantages become apparent. Most of the farmer households are weak in financial strength and their limited investment is put into the management of their orchards, which are usually small in size. They lack enough technical support, market information and channels for marketing their fruit beyond local market. As a result, farmers and smallholders compete bitterly on the local market. In years with bumper harvest they produce more than the local market can digest, and most of them suffer big losses. The orchard management standard and cultivation techniques are different among orchards, and thus the yield and quality of fruit produced by different farmers differ. Such a production system can no longer produce high economic benefit.

Climatic constraints

Although lychee cultivation techniques have improved a lot in the past 10 years, lychee production is still largely dependent upon climate. In general, the climate in the lychee production regions in China is favourable for lychee growth and development, but there are still unfavourable climatic conditions in South China that cause crop loss and/or irregular bearing. They are:

Frost

Lychee is susceptible to frost. Though it is rare in lychee production regions, its damage is severe once it occurs. In late December of 1999, a frost resulted in massive damage to lychee orchards, especially the new ones and those in low places. Lychee production loss caused by this frost damage in Guangdong alone was estimated to be 400,000 tons.

Humid autumn and warm winter

In South China, autumn is usually dry and winter is dry and chilly. The long autumn and winter drought plus chilly winter (temperature below 15°C in the day and 10°C in the night) is essential for lychee flower induction. Humid autumn and warm winters are unfavourable for winter shoot growth. Such kind of weather occurred in 1998 and most mid- to late-season cultivars failed to flower resulting in an off-year for these cultivars.

Cold and rainy spring

Most lychee cultivars flower in spring, when cold and rainy weather frequently occurs. Cold or rainy weather inhibits bee activity and causes diseases to the trees. This kind weather happening during the lychee bloom period is very harmful to pollination and subsequent fruit set and may cause severe crop loss.

Typhoons

The typhoon season usually starts from June in China, when lychee fruit of mid- and late-season cultivars are maturing. The strong wind of typhoons causes heavy damage to the trees and severe fruit drop. The heavy rainfall brought by typhoons usually causes serious fruit cracking to some susceptible cultivars like ‘Nuomici’ and ‘Guiwei’.

The development of lychee fruit happens to be in the rainy and humid spring and summer in South China. Rainy and humid weather not only increases the incidence of fruit drop and cracking, but also brings diseases and pests as well as difficulties in their management. Rainy weather during the harvesting period reduces the storability of lychee fruit remarkably and brings difficulty in post-harvest handling and heavy post-harvest loss.

10. GOVERNMENT POLICIES AND PLANS FOR RESEARCH AND DEVELOPMENT OF LYCHEE

Facing the entrance into WTO, the Government of China has attached great attention to improving the competitiveness of domestically produced fruits for the international market. Lychee is considered as one of the most competitive fruits in China for the international market. However, presently only a tiny portion of the fruit is exported.

The guiding principle of the Government in China for future fruit production is “to adjust regional distribution and species or cultivar structure, and improve the quality, unit yield and economic benefit based on the existing orchard area”. This policy aims to acquire a more sustainable fruit production and to increase the benefit by improving unit yield and quality instead of by expanding the area. As for lychee, this policy together with various constraints has remarkably reduced the boom of lychee orchards in the past few years. In order to acquire a rationalized cultivar structure that extends the production season of lychee, selection, breeding and propagation of high quality early lychee cultivars and extreme late-season ones is an important resolution, and relevant programmes have been given heavy financial support.

The poor storability and short shelf-life of lychee fruit are still the toughest problems that need urgent resolution in view of the rapid increase in lychee production. Research programmes on the mechanisms and control of lychee browning, cultivation measures to improve lychee storability, breeding and selection for more storage-endurable cultivars, and technology for safer and longer storage and transportation of lychee fruit have been strongly supported by all levels of government.

Irregular bearing of lychee caused by multiple factors is another aspect giving much concern. Research programmes have been conducted to clarify mechanisms of flower induction, fruit setting, cracking susceptibility and quality formation so as to formulate relevant technical strategies to ensure flower induction, improve fruit set and quality and prevent fruit cracking.

Integrated management of pests and diseases and environmentally friendly orchard management (e.g. green food fruit production and organic farming) are encouraged by the Government to bring about sustainable fruit production while protecting the biodiversity in orchards and improving fruit safety. Relevant research is underway in China. Techniques of green food lychee and other fruit production are being formulated.

In order to increase lychee export, the Government is encouraging large corporations with financial strength to join the lychee industry. These large corporations will be able integrate large scaled fruit production, post-harvest handling, marketing and exporting into a whole business. Governmental support is also given to the establishment of so called “Dragon-head enterprises”, which are actually large fruit dealers who do not produce much fruit by themselves but are mainly involved in post-harvest handling (storage and transportation), marketing and exporting of fruits purchased from the farmers or smallholders. With these enterprises, the farmers will not worry about marketing their fruits but concentrate on orchard management. These enterprises, with technical support from lychee researchers, are to help farmers to formulate and implement upgraded and standardized orchard management in order to obtain stable and high yield and quality fruits. The cooperation between these enterprises and lychee farmers will bring mutual benefit to each other, improve the marketability of lychee fruit and promote the sound development of the lychee industry.

11. CONCLUSIONS

Although lychee production has a long history in China, it did not become an important industry until the 1980s. The current output of lychee has saturated the local markets in South China. There is a very large potential domestic and international market for the future development of lychee production. However, major constraints of short shelf-life and the poor storability of the fruit, the short production season, the low efficiency marketing system, irregular bearing, and unorganized production by individual farmers or smallholders are blocking the sound development of the lychee industry in China. Government, researchers, extension services, corporations and growers have to make joint efforts to tackle these constraints.