Gi-Cheol Song*
*Agricultural Researcher, Fruit Cultivation Division, National Horticultural Research Institute, Rural Development Administration, Suwon, Republic of Korea.1. INTRODUCTION
Some wild species of grapes like Vitis amurensis and Vitis coignetiae found in the Republic of Korea are not commercially important species. Several cultivars grown until now were introduced through China from Europe, and found their way to Asia during the Koryo Dynasty around the 14th century. Modern viticulture began around 1906 when an experimental station was established to test imported cultivars. The wine industry began in 1910 in Kyongbuk Province. Some cultivars for wine were imported from USA, Europe, and Japan. These have been grown throughout the country since 1960.
The income from grape growing in the Republic of Korea is much higher when compared with that from other fruits. But over-production due to the rapid increase in grape growing areas and the high amount of imported grapes has brought about economic difficulties to local farmers. Presently, grape consumption is increasing because of the high national income and the superior quality of grapes. Grape production will boom as a promising industry if the quality of berries could be improved and the operating cost reduced.
2. PRESENT STATUS OF GRAPE CULTIVATION
Grape Cultivation Areas and Yields
From 1994 to 1998, the area planted to grapes expanded at an average annual rate of 11.5 percent. Correspondingly, production grew at an average rate of 18.3 percent (Table 1). The increasing trend of the area and the volume of production can be attributed to many factors, such as increasing consumption as a health food, ease of cultivation compared with other fruit crops.
Table 1. Area and Production of Grapes in the Republic of Korea, 1994-1998
|
Year |
Area (ha) |
Production (tonnes) |
|
1994 |
19,773 |
211,930 |
|
1995 |
26,030 |
316,443 |
|
1996 |
27,196 |
357,274 |
|
1997 |
28,290 |
393,195 |
|
1998 |
29,871 |
397,784 |
Table 2. Area, Production, Yield, and Consumption of Grapes in the Republic of Korea, 1995-1999
|
Year |
Area |
Production (1000t) |
Yield (t/ha) |
Consumption (kg/person) |
|
|
Mature Vine Cultivation (1000 ha) |
Young Vine Cultivation (1000 ha) |
||||
|
1995 |
14.3 |
11.7 |
316.4 |
12.2 |
7.1 |
|
1996 |
15.7 |
10.9 |
357.3 |
13.1 |
7.8 |
|
1997 |
20.5 |
7.1 |
393.2 |
13.9 |
8.6 |
|
1998 |
22.8 |
6.2 |
397.8 |
13.5 |
8.9 |
|
1999 |
23.9 |
6.6 |
470.0 |
15.4 |
10.0 |
Table 3. Area and Production of Grapes by Province in the Republic of Korea
|
Province |
Area (ha) |
Production (t) |
|
|
|
|
|
Seoul |
- |
- |
|
Pusan |
- |
- |
|
Taegu |
993 |
7,805 |
|
Inchon |
184 |
2,031 |
|
Kwangju |
225 |
3,159 |
|
Taejon |
588 |
7,891 |
|
Ulsan |
8 |
46 |
|
Kyonggi |
3,086 |
50,549 |
|
Kangwon |
140 |
1,599 |
|
Chungbuk |
4,507 |
51,200 |
|
Chungnam |
3,265 |
41,335 |
|
Chonbuk |
1,432 |
18,530 |
|
Chonnam |
582 |
7,112 |
|
Kyongbuk |
13,703 |
193,897 |
|
Kyongnam |
1,150 |
12,512 |
|
Cheju |
8 |
118 |
|
|
|
|
|
Total |
29.871 |
397,784 |
The distribution of grape cultivars is dependent on the prevailing climate in The Republic of Korea. European cultivars cannot be grown without ‘heeling’ under the soil in winter in the northern areas. Many American cultivars and their hybrids with European cultivars can however, be grown using this method. The ‘Campbell Early’ cultivar occupies 66.4 percent of the total area cultivated to grapes. The ‘Kyoho’ variety occupies 14.5 percent, and ‘Sheridan’ 11.8 percent. These three occupy 93.5 percent of the total area planted to grapes (Table 4). Various varieties of good quality are currently needed to compete against imported grapes.
Table 4. Number and Percentage of Area Planted to Grape Cultivars
|
Cultivar |
Area |
|
|
1992 ha (%) |
1997 ha (%) |
|
|
Early |
|
|
|
Campbell Early |
7,837.7 (69.8%) |
15,419.3 (66.4%) |
|
Seneca |
- |
219 (0.1) |
|
Alden |
- |
8.0 (0.003) |
|
Others |
58.1 (0.5) |
64.0 (0.3) |
|
Mid |
|
|
|
Kyoho |
1,178.4 (10.5) |
3,359.0 (14.5) |
|
Black Olympia |
72.8 (0.6) |
128.5 (0.6) |
|
Seibel 9110 |
913.9 (8.1) |
94.5 (0.4) |
|
Delaware |
63.1 (0.6) |
79.4 (0.3) |
|
Neo Muscat |
92.0 (0.8) |
64.3 (0.3) |
|
Fujiminori |
- |
13.0 (0.06) |
|
Pioneer |
- |
7.0 (0.03) |
|
Others |
214.3 (1.9) |
247.5 (1.1) |
|
Late |
|
|
|
Sheridan |
- |
2,741.8 (11.8) |
|
M.B.A. |
7.9 (0.07) |
492.4 (2.1) |
|
Tano Red |
186.2 (1.6) |
396.9 (1.7) |
|
Muscat of Alexandria |
- |
34.2 (0.2) |
|
Others |
299.2 (2.7) |
68.2 (0.3) |
|
Unclassified |
356.0 (3.2) |
0.2 (0.01) |
|
Total |
11,219.6 (100) |
23,239.9 (100) |
Table 5. Volume of Grapes Used for Processing, 1998
|
Products |
Volume (t) |
|
Canning |
2,590 |
|
Juice making |
6,422 |
|
Jam |
1,038 |
|
Liquor |
1,800 |
|
Vinegar |
391 |
|
Fruit Drinks |
4,922 |
|
Others |
803 |
|
Total |
18,279 |
Until recently many farmers grew grapevines without using rootstocks. There has been little infestation by grape phylloxera owing to the hot and rainy weather in summer and cold conditions in winter. It is reported that the grape phylloxera was present in some regions in 1912-1913. In 1998, phylloxera emerged in Cheonan and Anseong areas where mostly the ‘Kyoho’ cultivar is grown, but its spread has been nearly brought under control at present. To protect the grape from phylloxera and increase yield and colouration of berries, many farmers in The Republic of Korea began to use grafted grapevines. In some important regions like Cheonan, Anseong, Naju, Youngdong, and Kimchoen, farmers try to mass produce grafted nursery plants using rootstocks such as 5BB, SO4, 3309, 3306, 5C, and 8B etc. In addition there are some Agricultural Extension Services which plan to produce virus-free plants to supply their farmers.
4. ESTABLISHMENT OF VINEYARDS
Land Preparation
Precipitation in the Republic of Korea is more than 1,000mm a year, with almost half of it falling during June and July. This makes drainage installation important for vineyards. Considering the resistant level of grape cultivars against winter coldness, farmers are recommended to plant European cultivars in the areas where the minimum temperature is above -15°C and for American cultivars, above -20 to -25°C. Grapevines should be heeled to overcome these critically low temperatures during winter. The cultivars growing in the Republic of Korea have a large range of soil adaptability; hence planting vines on plains and slopes is possible. Generally, farmers prefer to plant grapevines in sandy loam soils. They make agricultural roads between vineyards for power tillers to operate and grow rye cereals or clovers as cover crops to avoid soil erosion.
Planting Season
Grape growers plant vines from November after leaf fall to the end of March when their roots start to revive. Generally, they prefer to plant grapevines in spring to avoid winter injury. Planting nursery stock is recommended before the end of March.
Spacing
Vine spacing is different according to varieties, rootstocks, soil fertility and other management techniques. To establish the Wakeman’s system for ‘Campbell Early’ grapes, it is recommended to have spacings of 3.6m x 2.7m (1,000 vines/ha) on fertile soils and 2.7m x 2.7m (1,370vines/ha) on poorer soils. In the Republic of Korea, every other plant is removed when the distance between rows is less than 1.8 - 2.4m.
In the shelf system for ‘Kyoho’ grapes, plants usually have a spacing of 1.8m x 3.6m at the beginning and then 3.6m x 3.6m in 4th - 5 th year, the spacing of 5 - 6m in the row is acceptable.
5. CARE AND MANAGEMENT OF VINEYARDS
Training and Pruning of Vines
The shelf system, which has short and long canes according to the diameters of canes, is used for the ‘Kyoho’ grape variety. The umbrella system is also used, but this form is difficult to control when vines are fully grown. This should be changed into a simple and an effective form, which is appropriate for plastic culture. It is advisable to get 1cm-thick bearing mother canes for ‘Kyoho’ grapes. Each shoot of ‘Campbell Early’ grapes has an average of 1.5 clusters. Two buds are needed from each bearing spur branch and a shoot is chosen out of the lower part from the two buds.
Application of Manure and Fertilizers
Farmers apply fertilizers separately. Basal fertilizers are applied after leaf fall in November up to pre-sprouting stage in March. Grape growers apply slow releasing manure and a little more fertilizers to provide nutrient element requirements. They supply all of the phosphorous and lime at the same time. More fertilizers are sometimes applied from the end of May to the beginning of June. In this case, 20-30 percent of nitrogen and 40 percent of potassium should be applied at the berry enlargement stage. Sometimes farmers supply a small amount of fertilizers after harvest for recovery of vine vigor. Urea application on leaves to supplement nitrogen is also useful. After manure and fertilizers have been evenly applied on the surface of the soil, a tiller is used to plow and turn the soil.
Weeding
Too much rain during the vine growing season makes grasses grow well. Many farmers use herbicides 3-4 times a year to control weeds. Some farmers are also increasingly using cover crops like rye cereals and clovers to control soil erosion and weeds.
Supplementary Irrigation
The Republic of Korea has sufficient rainfall (1,000~1,300mm per year), but 40-50 percent of this precipitation occurs during July and August. Sometimes, irrigation is required from the beginning of May to the end of June. Precipitation from September to October is not enough; hence supplementary irrigation is necessary.
Pests and their Management
The common pests in the Republic of Korea are grape tiger longhorn, grape clearwing moth, grape leafhopper and yellow tea thrips. In 1998, grape phylloxera infected areas were found in some regions, but the infected areas are no longer increasing at present. Generally, farmers use insecticides about 10 times a year. However, some farmers apply these chemicals less than 3-4 times a year by using plastic houses.
Diseases and their Management
The common diseases in the Republic of Korea are bitter rot, leaf spot, downy mildew, powdery mildew, gray mold and anthracnose. In 1998 and 1999, bitter rot, downy mildew and anthracnose were a little severe due to heavy rains lasting until harvesting time.
Physiological Disorders
Poor sprouting and bud necrosis at the early growth stage, berry shattering, and cluster stem dehydration are conditions observed in relation to cluster formation. Sometimes, excess and deficiency of nitrogen, potassium, magnesium and boron are common. Many disorders occur under abnormal weather conditions. There is sunburn on berries and leaves, berry cracking and water berries. Very severe berry cracking and water berries occurred in 1998 and 1999. The search for solutions to these disorders is being undertaken through several research studies.
Other Factors such as Grape Quality Improvement
Plastic culture is the best method to improve berry quality, and so it has been popularized. Many growth regulators like GA, KT-30, and ethephon are being used to induce seedless grapes, berry enlargement, hastening and delaying harvest, cluster elongation, and improvement of berry setting. Sometimes improper application creates problems. Many farmers use products made commercially, and also produce their own formulations themselves even if their efficacies are not proven.
6. HARVESTING AND YIELDS
Grape yield is increasing annually due to the increase of grape cultivation area and advanced grape growing skills. Grape production in 1994 was 211,930 tonnes and reached 397,784 tonnes in 1998. In 1999, the production of grapes was estimated at around 470,000 tonnes because of increased growing area of mature grapevines. Growing grapes is much easier than other fruits; therefore farmers can easily get a good income. Berry shattering occurs every year especially in ‘Kyoho’ grapes, but this does not seriously affect grape production. In spite of bad weather conditions, farmers keep having good income because of excellent berry quality under plastic houses and their growing skills. The consumption of grapes has also been increasing steadily.
7. MARKETING
Grapes are sold through Agricultural Cooperative Associations, Producers’ Cooperatives, by the roadside, and at department stores. The Republic of Korea exports ‘Delaware’ grapes to the South East Asian markets and sometimes to Japan, but also imports wines, juice and table grapes. Table grapes like ‘Red globe’, ‘Thompson seedless’, and ‘Flame seedless’ are imported from Chile and USA, and since the change of the import policy in 1996, imports are increasing (Table 6). It is assumed that much more table grapes will be imported after the conclusion of the Free Trade Agreement in Agriculture between the Republic of Korea and Chile. At the same time the local price of grapes has declined since 1994 due to over-production.
Table 6. Import and Export of Grapes in the Republic of Korea, 1996-1999
|
|
1996 (tonnes) |
1997 (tonnes) |
1998 (tonnes) |
1999* (tonnes) |
|
Import |
2,403 |
8,896 |
1,112 |
6,200 |
|
Export |
1 |
0.02 |
75.5 |
155.4 |
8. POTENTIAL FOR GRAPE PRODUCTION DEVELOPMENT
The Government of the Republic of Korea recommends that farmers do not plant grapevines anymore. But some farmers continue to grow vines because they do not have other alternative crops. Farmers try to produce good quality grapes and they are making grape juice and wines for themselves. In some regions, farmers grow a hybrid cultivar between a wild Asian variety and an American cultivar to produce a popular wine and juice. But its quality is variable according to the different methods used by farmers to produce wine.
9. CONSTRAINTS IN GRAPE PRODUCTION DEVELOPMENT
Growers are supposed to apply chemicals about 10 times a year, but this frequency is reduced to less than 3 - 4 times by using plastic houses. Recently, the grape crop has had several physiological disorders like berry shattering, berry cracking and water berries under abnormal weather conditions. It is necessary to process surplus grapes and export more fresh grapes. This may lighten the farmers’ burden caused by excessive production. Grape growing farmers should produce grapes of good quality under plastic houses and install irrigation systems. They also need some technical help like soil testing and continuous education of growers on new techniques.
10. GOVERNMENT POLICIES AND PLANS FOR RESEARCH AND DEVELOPMENT ON GRAPE PRODUCTION
The Government discourages farmers from growing grapes and no financial help is provided. Despite this situation, many researchers are still conducting studies on the pests, diseases and physiological disorders of grapes. Some courses are organized by Government organizations to train farmers on these aspects.
11. CONCLUSIONS
Table grape cultivation areas in the Republic of Korea have greatly increased recently. It is necessary to solve the problem of over-production. In spite of different growing skills according to regions and individual farmers, well developed growing techniques help other farmers. The wine industry is not well developed and is carried out on a very small scale at present. Specifically, high quality wine making is difficult due to the weather conditions. To solve excessive grape production, the country should process and export grapes. However, the level of knowledge and skills in grape processing is still limited. Continuous dispatch of specialists for training in other countries with advanced skills is necessary. Financial support is also needed for research and development projects on high quality grape production and processing.
