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The summer fruit tortrix moth (Adoxophyes orana) is an important pest insect in orchards. In 2004, the first cases of insecticide resistance were observed in the canton Vaud and recently fruit growers of the Valais indicated a reduction in insecticides’ effectiveness. In 2008, a survey conducted in the Valais showed that the amount of apples and pears damaged by A. orana was generally low. However, moth’s abundance is heterogeneous and larval development is poorly synchronised between orchards. Thus, a large variability between A. orana’s flight periods was observed among sites. Besides, moths flew for a third time in September. The assessment of an indoxacarb application in a commercial orchard indicated that the insecticide was still efficient. This observation was confirmed by the analysis of different active ingredients in the laboratory. Larvae of A.orana originating from a single orchard in the Valais were exposed to five different insecticides by the dipping of leaves. At the 99% lethal dosage, indoxacarb, methoxyfenozide and tebufenozide killed all exposed larvae. However, the tested strain was slightly resistant against chlorpyrifos-methyl and fenoxycarb. Overall, we strongly recommend the careful monitoring of A. orana’s population dynamic within orchards and a regular alternation between the different chemical, biotechnological and biological classes of active ingredients applied.

Keywords: Key words: Tortricidae, pomiculture, pesticide use, resistance management.

E-Mail: patrik.kehrli@agroscope.admin.ch

Adress: Agroscope, 1260 Changins/Nyon

During 2001-2003, a study was conducted in Valais in order to analyze the various interactions between the green leafhopper (Empoasca vitis Goethe) of the vine and the Pinot noir grape. In this region, green leafhopper is characterized by a more important first generation than the second one, which develops over a rather long period. The plant slightly reacts to the pressure of first generation’s juvenile stages, which colonize primarily the first five leaves from the base of the shoot. The pressure of leafhopper correlates to the leaf damage percentage and influences the basic water potential of the plant, inducing a weak water stress. No quantitative and qualitative vintage parameters could be correlated to the pressure of E.vitis. The plant did’nt compensate leaf damage by increasing the number of secondary leaves. The vines may have compensated the pressure of the green leafhopper by mobilizing their reserves or the pressure observed during this study could be not sufficient to induce the plant to compensate damage. Results show that the control of the first generation can be abandoned and that tolerance level for the second generation could be extended to two leafhoppers per leaf as far as the vine grower can avoid inducing other types of stress such as excessive leaf removal during the ripening of grapes or an imbalance between weight and leaf surface.

Keywords: Key words: threshold levels, Vitis vinifera, basic water potential, control, leaf damages, Empoasca vitis.

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

Adress: Agroscope, 6593 Cadenazzo

Golden root or roseroot (Rhodiola rosea L.) is a dioecious and perennial plant of the
Crassulaceae family. This arctico-alpine species is widely used in traditional medicines
in Russia and in Scandinavia to fight against stress, to stimulate the immune system
and to increase physical and mental performances. The active compounds, mainly
salidroside and rosavins, are stored in the rhizomes whose characteristic rose odor
gave its name to the plant. Since 2005, Agroscope Changins-Wädenswil Research Station
ACW is working on the domestication of alpine R. rosea. The phytochemical and
morphological study of 93 individuals from five natural populations in the Swiss Alps
shows a high content of active compounds as well as an important variability within
and between populations. Except for the population of Mattmark (VS), particularly
rich in salidroside, the phytochemical profiles of all the populations studied are relatively
similar. In addition, no significant difference was found between female and
male plants. The essential oil content is generally very low and varies greatly from one
individual to another. The large variability observed provides a wide choice for a future
breeding program by using R. rosea individuals with the best balance between
biomass and content of active compounds.

Keywords: Rhodiola rosea L., Golden root, Roseroot, Swiss Alps, domestication, salidroside, rosavin, essential oil.

E-Mail: claude-alain.carron@agroscope.admin.ch

Adress: Agroscope, 1964 Conthey

The orchard management of four integrated and four organic farms was observed in the lower Elbe region (D) for three years as part of the EU Isafruit-project. On average the yield of the organic orchards was 30% lower than that of the integrated orchards. In spite of those lower yields and higher looses during storage, organic farmers get twice higher producer prices and therefore higher proceeds. Beside yield depending harvest costs, organic farms must afford higher labour costs dut ot increased manual work in relation with the lack of chemical pesticides. Altogether the four organic orchards had anyway lower labour costs because of smaller working hours need for harvesting, grading and storing due to lower yields.

Keywords: farm management, Isafruit-Project, integrated orchard, organic orchard.

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The production technique is of great influence on the productivity of apple orchards. Five hypotheses are formulated to verify the impact of yield (kg/ha), cultivar, area of apple production and plantation density on productivity. The data used in this study were collected fromtrenta professional apple producers within the project Support Obst Arbo.

Keywords: apple production, productivity, crop, cultivar, orchard area, plantation density.

E-Mail: esther.bravin@agroscope.admin.ch

Adress: Agroscope, 8820 Wädenswil

‘Chasselas’ is one of the most widespread white grape varieties in the world. There are several legends about its origins: it could have been brought back from Egypt or Turkey, it could have been born in France or Switzerland, etc. The earliest mentions of ‘Chasselas’ occur in the 16th and 17th centuries, first in Württemberg (D), then in Burgundy (F) and in the canton of Vaud (CH). A genetic study based on 511, 317 and 132 varieties from Europe and the Near East analyzed at respectively 11, 20 and 54 molecular markers (microsatellites) allowed to reject the possibility of an Eastern origin for ‘Chasselas’, and to locate its cradle at the crossroads between Switzerland, France and Italy. Combined with historical data, genetic analysis points out the Lake Geneva region as the most likely center of origin for ‘Chasselas’, particularly the canton of Vaud where the diversity of forms was the most important during the 19th century.

Keywords: grape cultivar, kinship, microsatellite, Switzerland, Gutedel.

E-Mail: jose.vouillamoz@agroscope.admin.ch

Adress: Agroscope, 1964 Conthey

The photosynthetic capacity of Chasselas leaves according to the grapevine water status was studied from 1994 to 2005 on Agroscope Changins-Wädenswil ACW research vineyards. In the absence of water stress, the stomatal conductance and the photosynthesis of the leaves photosynthesis are maximal. The increase of water constraint leads progressively to stomates closure and reduction of photosynthetic activity. During a light water stress, photosynthetic activity is reduced by 15 to 20% and could even fall down to 50% when water stress becomes severe (predawn leaf water potential under -5 bars).

Keywords: grapevine water status, leaf water potential, photosynthesis, stomatal conductance.

E-Mail: vivian.zufferey@agroscope.admin.ch

Adress: Agroscope, 1009 Pully

Les conditions de stockage recommandées pour la variété La Flamboyantecov-Mairac® subissent de petites modifications. Les variétés Jonathan et Florina ont passé dans la rubrique «autres variétés». De nouvelles variétés feront leur entrée dans la liste prochainement (Pink Lady®-Cripps Pinkcov et Jazz®-Scifresh, etc.), dès que leurs conditions optimales de conservation seront mises au point.

Keywords:

E-Mail: jean-pierre.siegrist@acw.admin.ch

Adress: Office fédéral de l'agriculture