SWITZERLAND I. History and Production Trends When the first potatoes were brought to Switzerland, they were considered courious botanical rarities. The Swiss botanist from Basle, Caspar Bauhin, described the potato plant for the first time in 1596, using the term Solanum tuberosum. In 1727, for the first time indications are given about potato cultivation on the farm "Gummi" in the canton of Schwyz. Today, people living in this region still use the term "Gummel" for potato. Other terms in the German speaking part of Switzerland are "Happere" (Erdbirne), "Hardopfel" (Erdapfel) or "Harpfel" (term used in the Upper Valais). In the French speaking part of Switzerland people often use the colloquial term "patate" instead of "pommes de terre". In the Italien speaking Ticino the following terms are used: "pom da terra" or just "pom" (Versasca valley), "bal" (from patati) and "gnucc" (Blenio valley). Even in the small Romansh speaking part of Switzerland, different terms are common: "Mailinterra" (apple in the ground) and "Ardoffel" in Ladin dialect, "Tartuffel" in Grischun dialect, "Truffel" in Sursilvan dialect and "Tiffel" in Surmiran dialect. During the 18th century, when reglementation about compulsory cultivation was liberalized, the potato became established as a crop. In times of interrupted supply potato cultivation was extended. In 1944 for example, the acreage measured 85,000 hectares. Potatoes were then used both as food and as animal feed. In times of economic prosperity the crop area was diminished again. During the last years potatoes were cultivated on a area of 19,000 to 20,000 hectares. FAO estimates of potato area and production for 1961-1995 are shown in Figures 1 and 2. 2. Production Zones Today, potato production in Switzerland is wide-spread in the areas north of the Alps between Schaffouse and Geneva, especially in the canton of Berne. The high average yields demonstrate that the climate in the main production areas is appropriate to the cultivation of Potatoes though temperatures in summer sometimes exceed the optimum. Therefore, outstanding yields are more likely achieved in years with rather cool temperatures. Table 1 indicates the development of average potato yields. Up to now the highest average yield was achieved in 1981 with 48.9 tons per hectare. In typically warm regions in Ticino and at the Lake of Geneva early potatoes are cultivated, but without much influence on the maincrop production. In altitudes of 1000 m and more yields often are as good as in lower regions. In dry alpine valleys potatoes can be cultivated up to 2000 m, e.g. in Lu (Munster valley, Grisons) on 1900 m and in St. Niklaus (Valais) on about 2000 m. Table I Average potato yields in Switzerland ______________________________________ Years Yield (tons / ha) ______________________________________ 1945-51 18,3 1952-56 22,6 1957-60 28,4 1961-65 30,3 1966-70 34.3 1971-75 39,9 1976-80 39.7 1981-85 43,5 1986-89 43,3 _____________________________________ Seed potatoes are mainly cultivated in hill country of the Lower Alps. In these regions (600 to 1000 m above sea level) potato crops grow fast and the tubers develop before aphids fly thereby avoiding infestation. Local differences exist. For example potato crops in a valley are more likely infested by virus transmitting aphids than hilltops exposed to winds. In lower altitudes north of the Alps farmers try to make up the disadvantage of an unfavourable site by giving special care to tillage and cultivation and by choosing isolated fields. A map of the major potato production zones in Switzerland can be found in Figure-3. 3. Production a. Seasons In Ticino and at the Lake of Geneva potatoes are planted late in February to early March and are harvested beginning in the last days in May. Seed potatoes and main crop potatoes are planted mainly in April. The harvest of ware potatoes and potatoes for processing is usually done in September. The haulms of the seed potatoes are killed late in June until late in July, depending on the aphid population, potato variety and altitude. b. Seed Sources and Varieties Most of the seed used during the last years was multiplied in Switzerland, i.e. 97 to 99 %. Farmers covered about 75 % of their requirements with certified seed. By one or two multiplications on their own farm they produced the other 25 % of the necessary seed. Above all this is the case for virus resistant varieties. In 1989, the official list of varieties in Switzerland included 22 varieties. On table 2 the acreages for the most important varieties are indicated. At present, the acreage of the following varieties is being extended:Nicola, Charlotte, Agria, Granola, Hertha. Table 2. Leading varieties in 1989 ___________________________________________________________ Early potatoes Ware potatoes Potatoes for processing ______________________________________________________________________ Ostara 45% Bintje 50% Eba 62% Sirtema 37% Desiree 19% Erntestolz 15% Charlotte 10% Urgenta 15% Hertha 8% Others 8% Others (5) 16% Others (6) 15% Total 100% 100% 100% ______________________________________________________________________ c. Production practices Potato cropping is done almost exclusively by private farmers. Some farmers only cultivate small acreages, chiefly for self-sufficiency. Others have several hectares and supply the market. The usual row distance is 75 cm. Recommended plant density for seed potato production is 50000 plants per hectare, for ware potato production 40000 to 50000 plants per hectare depending on variety and intended purpose. General fertilizer recommendations are as follows: _________________________________________________________ Seed potatoes and Ware potatoes and early potatoes potatoes for processing --------------------------------------------------------------------------------------- N 50 to 120 kg per hectare 60 to 140 kg per hectare P2O5 70 110 K2O 190 300 _________________________________________________________ Most farmers follow a crop rotation which includes potato crops every 4 years at the most. Irrigation has become more and more common. In lower altitudes north of the Alps where the major part of potatoes are cultivated, potato production is fully mechanized. Farmers often use two-row fully automatic cup-planters and they mostly prefer one-row. d. Diseasesand Pests In some regions potato cyst nematodes are found. But most farmers follow a long crop rotation so that these nematodes are not very wide-spread. The most important fungal disease is late blight (Phytophthora infestans). Crop losses are more severe in the humid regions of the central and eastern parts of Switzerland than in the west. Without some plant protection measures potato production would not be economical. Attempts are made to reduce the application of pesticides. Sometimes in different regions Erwinia sp. causes problems. Among virus diseases virus Y and potato leafroll-virus dominate. The use of insecticides in seed potato crops against virus transmitting aphids is not permitted. 4. Post-Production a. Storage About 80 % of the potatoes are stored in transportable storage bins by co-operatives or private companies. Most of the storage areas are equipped with forced outside air ventilation or cooling systems. b. Preparation, Consumption and Marketing In 1988, the crop was utilized as follows: 50 % animal feed 44 % human consumption 5 % seed 1 % export. In 1970, more than 70000 tons of ware potatoes were exported. Export rates then continously decreased. 1988 it was possible to export about 8000 tons of seed potatoes. During the last years the figure of potatoes for human consumption stabilized at a level of 410,000 tons. In 1988/89, 119,000 tons (29 %) were processed, chiefly for French fried potatoes (53 %), chips (18 %) and flakes (14 %). Most potatoes still are consumed as boiled potatoes. Fresh potatoes are sold by private enterprises or co-operatives mostly in bags of 2.5 and 5 kilogrammes or they are sold directly by the farmers. Prices are state-controlled. Since several years, the annual potato consumption is of the order of 65 kilogrammes per capita. REFERENCES Koblet R., 1965. Der landwirtschaftliche Pflanzenbau. Birkhduser-Verlag.Basel und Stuttgart. Winiger F.A. 1988. Tatigkeitsbericht der Schweizerischen Vereinigung fur Kartoffelsorten (SVK). JURIS Druck- und Verlag. Zurich Flachenstatistik 1989. Eidg. Alkoholverwaltung Bern.