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Management of climate conditions in the glasshouse using temperature integration (TI) over a 24-hours period is one of the ways to achieve energy savings. A trial carried out from 2007 to 2009 in roses on substrate showed that an energy saving potential of 9.8% is possible with TI. TI neither influenced the yield in number of shoots/m2, nor the shoot lengths or the vase life. On the other hand, white fly and powdery mildew pressure was locally higher with TI. The results confirm that temperature integration is a useful method to save energy in roses cultivation on substrate.

Keywords: energy saving, shoot length, vase life.

E-Mail: celine.gille@agroscope.admin.ch

Adress: Agroscope, 1964 Conthey

1-MCP (SmartFresh™), an inhibitor of ethylene action, was tested under ULO (Ultra Low Oxygen) atmosphere during three years with Mairac® apples. In one year, the influence of two temperatures (2 °C and 3 °C) was analysed under these storage conditions. The application of 1-MCP reduced dramatically the decrease in firmness of the Mairac® apples. However, the decline in malic acid of these apples was reduced only slightly. Under all tested conditions storage, diseases were partly observed. Under ULO conditions, 1-MCP increased the cavity development. Apples with soft scald were more often observed at 2 °C storage temperature than at 3 °C. Furthermore, the brown core disease increased more or less from April, depending on the orchard. In conclusion, the results showed that the Mairac® apples had less storage diseases under ULO-conditions with a temperature of 2 °C temperature combined with an 1-MCP application.

Keywords: storage diseases, scald, firmness, malic acid, controlled atmosphere.

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Adress: Agroscope, 1964 Conthey

Seven chemotypes (or chemical types) of common thyme (Thymus vulgaris L.) have been described in natural Mediterranean populations: thymol, carvacrol, linalool, gerianol, sabinene hydrate, p-cymene and cineol. The discriminating power of the SMart Nose®, an electronic nose based on mass spectrometry of the gas phase, was tested on seven varieties from Switzerland, France and Germany representing four chemotypes previously distinguished by HPLC-DAD. This experiment shows that the distinction between the cultivars with the SMart Nose® is fast, reproducible and inexpensive. The use of the SMart Nose® could be extended in the future to other applications in medicinal and aromatic plants, such as screening of genotypes in natural populations and in F1 after crossing to detect a particular chemotype.

Keywords: Thymus vulgaris, Lamiaceae, aromatic plants, HPLC, spectrometry.

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Adress: Agroscope, 1964 Conthey

The elder aphid, Aphis sambuci L. is currently one of the most important pests of black elderberry, Sambucus nigra in Switzerland. Tests were carried out since 2004 to find a strategy compatible with organic farming in order to control the aphids. The control method has been developed by observing the presence of aphids on the 5 terminal umbels (50 branches/ha). The tests showed that the active principles Azadirachtin A and Pyrethrin/sesame oil, licensed in biological control, have a good efficiency (between 85 and 100% according to the variant). The first treatment should take place at the first appearance of aphids on umbels, either with Azadirachtin A or with Pyrethrin/sesame oil. A check 2 weeks after the treatment allows estimating the treatment’s effectiveness and if a second treatment is necessary. One treatment with Azadirachtin A at the beginning of the attack is generally efficient. However, a further application of Pyrethrin/sesame oil may be necessary after 15 days to obtain a good effectiveness.

Keywords: words: elder aphid, black elderberry, organic farming, Azadirachtin A, Pyrethrines/ sesam oil, strategy.

E-Mail: catherine.baroffio@agroscope.admin.ch

Adress: Agroscope, 1964 Conthey

On pourrait dire de Catherine Baroffio, cheffe du groupe plantes médicinales et petits fruits d’Agroscope ACW, qu’elle est un pur «produit» (!) Agroscope. En effet, elle a effectué l’essentiel de sa carrière professionnelle sur les sites de Wädenswil et de Conthey et maîtrise parfaitement le français et l’allemand. Son domaine d’activité, à la croisée des disciplines, est des plus «innovants» – pour reprendre un terme cher à la recherche agronomique suisse – et s’inscrit pleinement dans les projets de recherche Nutriscope (qualité alimentaire) et Agrimontana (rentabilité agricole en montagne).

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E-Mail: catherine.baroffio@agroscope.admin.ch

Adress: Office fédéral de l'agriculture

Two distinct clones of lemon thyme are cultivated in Switzerland: ‘Vol1’ and ‘Vol2’. To facilitate the organization of the sector of aromatic and medicinal plants, these two clones were characterized by Agroscope ACW to determine the optimum harvest stage and allow the selection of the most suitable clone.Yields, rate of leaves, essential oil content and sensory evaluation were characterized for these two clones. The clone ‘Vol1’ was preferred by farmers because of its erect growth. It has a better essential oil content (1.09-1.99%) with strong dominance of geraniol (62.3-85%). The clone ‘Vol2’ has the advantage of a high rate of leaves. Its flavour profile is more balanced between geraniol (29.5-54.4%) and citral a+b (16.37-31.50%) and was favoured by the tasters. The optimum harvest stage is before “full-bloom” for both clones, which meets the requirements of the industry.

Keywords: Thymus × citriodorus, essential oil, sensory evaluation, geraniol, citral.

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Adress: Agroscope, 1964 Conthey

The round-leaved saxifrage (Saxifraga rotundifolia L.) held attention of the cosmetics industry, constantly looking for new developments, because the plant shows interesting radical scavenging and antioxidant activities. Furthermore, its cultivation is feasible and its active compounds have been identified. The present study aims at evaluating the changes in the concentration of active compounds in the aerial parts of the plant depending on its origin, and at defining the optimum phenological stage of harvest based on the contents of phenylpropenoic acids, flavonols and flavonoid glycosides. The phytochemical profile was influenced by the origin of the plants. In full bloom, the concentration of chlorogenic acid (0.1% of the dry matter, DM), of quercitrin (0.4% DM) and of rhamnosid luteolin (0.02% DM) was high. The content of myricitrin (1.3% DM) reached its maximum at seeds formation, with a relatively small variation from the stage of full bloom. Based on these results, harvesting in full bloom is a good compromise between a high overall content of various phenolic compounds and dry matter yield.

Keywords: round-leaved saxifrage, harvest stage, radical scavenging, antioxidant, myricitrin.

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

Adress: Agroscope, 1964 Conthey

La caractérisation organoleptique de la réduction et l’identification des molécules incriminées dans ce phénomène ont fait l’objet d’un travail de diplôme à l’EIC.

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E-Mail: christian.guyot@eichangins.ch

Adress: Agroscope, 1260 Changins/Nyon