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Recently, the insecticide control of the summer fruit tortrix moth (A. orana) failed in two orchards at Etoy and Aigle in the Lake of Geneva region. Biological tests were carried out by dipping apple leaves in different concentrations of insecticides for rearing newborn larvae from the strains collected in these orchards. Compared with reference strains, these two populations proved to have developed a resistance of a factor 5 to 100 to two families of products, the benzoylureas (hexaflumuron and lufenuron) and the benzhydrazides (tebufenozide and methoxyfenozide). For the moment, resistance does not affect the neurotoxic insecticides indoxacarb, spinosad and chlorpyrifos-methyl. The development of the resistant strain seems to be slowed down, causing a delay in the course of the flight of the moths, which could allow to detect new cases of resistance.
Key words: summer fruit tortrix moth, Adoxophyes orana, Switzerland, insecticide,
resistance.

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Twelve old tomato varieties (no hybrids) belonging to various types of fruit forms were compared with five improved varieties (F1-hybrids) in a cold tunnel. This study informs about the agronomic and quality behaviour of these varieties cultivated as non-grafted plants. The results of analyses and tasting by semi-professional tasters determined the five most appreciated varieties: Sapho F1, Rose of Berne, Baselbieter Röteli, Climberly F1 and Pomodoro di Catenna. These varieties had high indexes of refraction (°Brix) and a citric acid content over 3,5 g/l. The ten other varieties, including other ox-heartvarieties, were less appreciated than the variety Climberley F1, the modern savour reference variety. Old varieties cannot be distinguished from modern ones by the contents of vitamin C and carotenoids (lycopene and ß-carotene). It is the colour of a tomato which mainly determines its carotenoids content (antioxidants).
Key words: old tomato, agronomic values, analytical values, taste value.

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The efficacy of nitrogen fertilization by applying foliar urea in grass-covered vineyards relatively sensitive to high nitrogen competition has been studied in the experimental vineyards of Swiss federal Research Station Agroscope Changins-Wädenswil at Pully (VD) and Changins (VD). The same nitrogen quantity (50 kg N/ha) applied on the leaves from June to August was better used by the plants than nitrogen added to the soil in spring. A reduced amount of nitrogen (20 kg N/ha) applied late in the season on the leaves (around veraison) brought about the same correction of nitrogen levels in the musts (formol index) as greater quantities (50 kg N/ha) applied to the soil in spring. The different modalities of nitrogen fertilization had little influence on vigor and productive potential of the vines. Corrections of nitrogen levels by foliar fertilization reduced the negative characters of the wines induced by water-nitrogen stress.
Key words: grapevine, nitrogen competition, nitrogen fertilization, urea, wine quality.

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E-Mail: jean-laurent.spring@agroscope.admin.ch

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A yield regulation trial by elimination of clusters after berry set was carried out on the cultivars Arvine and Cornalin at Leytron (VS). Three yield levels were aimed: 1,0 to 1,2 kg/m2, 0,7 to 0,8 kg/m2 and 0,3 to 0,4 kg/m2. It was not always possible to reach the aimed yield because of the attacks of bunch rot. The reaction to the reduction of the yield on the analytical and organoleptic point of view was more important for Cornalin than for Arvine. For Cornalin, the reduction of the yield below 0,8 kg/m2 still induced an increase of the sugar rate of the must. The acidity of the musts and the wines decreased with the reduction of the yield.
Key words: grapevine, yield level, cluster thinning, must composition, wine quality.

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E-Mail: dominique.maigre@bluewin.ch

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Direct seeding in the field of medicinal plant burnet saxifrage (Pimpinella peregrina) is not suitable in the climatic and environmental conditions of Ticino: the cultivation results heterogeneous with low densities of plants and, consequently, inadequate yields. During the period 1999-2001, a technique of transplant of plants prepared in polystyrene plates «Speedy» has been developed.This technique assured homogeneous plant densities and yields regularly higher than 30 kg dry matter/a. The seeding, operated through an automatic seed drill, must be carried out at the beginning of March in polystyrene plates, model Ecopot», whose square grooved holes permit to obtain sinker not too fibrous roots. The planting in the field is possible from April 15th in the lowland and from end of April in the mountain area. A density of 25 plants/m2 represents a good arrangement between yields, costs and cleaning work of the crop.
Key words: Pimpinella peregrina, burnet saxifrage, yield, seeding, potted plant.

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E-Mail: mauro.jermini@agroscope.admin.ch

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Strawberry production on substrate with everbearing varieties is expanding in Switzerland. In order to evaluate the new everbearing strawberry cultivars Charlotte, Diamante, Elsegarde, Elsinore and Flamenco, they were compared to Mara des Bois in substrate culture in 2003 and 2004. Moreover, the optimal plantation density was analysed.
For all the everbearing cultivars tested, the optimal plantation density was one plant per pot on the tubular system corresponding to 6 plants per linear metre. With this density, the yields are similar, but the planting, harvesting and culture maintenance costs are lower than those for two plants per pot. The Elsinore variety gave the best 1st quality yields with nearly 1 kg per plant, good fruit size but with average to good sensory quality. Charlotte and Elsegarde produced fruits of good to very good quality, with sizes similar to those of Elsinore but yields inferior of about 15%. Mara des Bois showed inferior yields and fruit sizes, about 40% lower than Elsinore. However, the sugar contents of its fruits was slightly higher than the one of Elsegarde and Charlotte. Flamenco and Diamante gave few yields, similar to the one of Mara des Bois. Diamante produced the biggest fruits in 2003.
In conclusion, the results showed that Elsinore offers considerable yields, Mara des Bois very good fruits and Charlotte and Elsegarde an excellent compromise between quality and yield.
Key words: everbearing cultivars, firmness, sugar content, sensory quality, yield.

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E-Mail: christoph.carlen@agroscope.admin.ch

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The so-called project «Support Obst-Arbo» (SOA) is a common initiative of the Swiss federal research station Agroscope Changins-Wädenswil (ACW), the Swiss center for agricultural Extension and rural development (Agridea) and the Federation of Swiss fruit producers (Swissfruit) to promote profitable Swiss fruit production. The work is based on detailed data generation on the farm, where the manager gets his data on a full cost basis at the variety level. Around 30 fruit farms in Switzerland participate to this project by using the software ASA-jAGRAR, daily documented by the farm managers. Those data are collected and controlled by the extensionalists and analysed and evaluated by the researchers. Through this «from farm to farm» approach, economical and technical informations can be detected and the management process can be optimized.
Key words: profitable fruit production, data generation, economical and technical information.

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