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The site effect of five locations from north (Stjørdal, Norway, 63 • 36 N) to south (Ancona, Italy, 43 • 31 N) was evaluated in strawberry regarding yield performance, fruit quality, length of fruit developing time from anthesis to harvest start and length of the harvest season. Cv. Elsanta was grown at all sites while cv. Korona was cultivated in north and central Europe and cv. Clery in central and south Europe. Yield was more affected by seasonal and growing conditions than by latitude. Anthesis was delayed as influenced by cultivar up to 58 days from south to north and was nearly maintained until harvest start. Duration of fruit development was negatively related to daily mean temperature and increased with higher latitude. 29-34 days were required from anthesis to harvest start for cv. Elsanta, 29-36 for cv. Korona and 27-38 for cv. Clery. Corresponding GDD values (growing degree days; 3 • C base temperature) were independent from latitude and accounted to 334-355 for cv. Elsanta, 301-385 for cv. Korona and 320-434 for cv. Clery. Daily mean temperature decreased about 2 • C from south to north during anthesis to harvest start which induced a calculated 5.2 days longer fruit development period in the north. From harvest start to harvest end, GDD values varied for all cultivars between 297-402 GDD showing no influence of the latitude. However, simple summing of GDD values do not correctly describe the time of fruit development (from anthesis to the ripe fruit) for the whole fruiting period of a plant. GDDs for individually tagged flowers increased notably from the first third to the last third of the developing period due to increasing temperature as the season proceeded. The fruit quality standards dry matter, soluble solids and titratable acidity were influenced by latitude giving northern sites in general the highest values. Fruits grown at the southern sites were redder compared to those of the north.

The effect of four different growing locations from Stjørdal, Norway (63 • 36 N) to Conthey, Switzerland (46 • 12 N) on the composition of bioactives in strawberry (Fragaria x ananassa Duch.) of three genotypes (cvs Clery, Elsanta and Korona) was evaluated. Principal component analysis (PCA) was used to characterize differences in bioactives between genotypes within a location. Despite harvest period and year-to-year effects, a clear clustering related to the effects of the cultivars was shown. Furthermore, PCA was able to separate locations within a cultivar due to differences in bioactive compounds and this effect was stronger than local variations by temporary weather changes or even year-to-year effects. As a result, the northern samples had principally lower anthocyanin amounts than the southern ones and, moreover, distribution of individual anthocyanins was different. In contrast, the content of vitamin C and the antioxidant capacity (TEAC, ORAC, total phenols) was generally increased with higher latitudes calculated on a fresh weight basis. Results of proanthocyanidins and individual polyphenols detected by high performance liquid chromatography indicated that the higher contents were mainly due to tannin-related components. For all these observations, cultivars responded in general similarly. A North-South division was identified but no clear trend towards latitude could be recorded, mainly since one major impact factor for the biosynthesis of phenolics and ascorbic acid is temperature, which is altering not only by latitude, but also by the shift of the harvest period and the current weather conditions prior to harvest. In conclusion, genetic effects were generally stronger than environmental effects.

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The mechanisms responsible for fluctuations in species composition of semi-natural grassland are not well understood. To identify plant traits that determine the poor competitive ability of Festuca pratensis compared to Dactylis glomerata especially during summer, the growth of both grasses was monitored over time and at different temperatures and photoperiods. Plants of both grasses were grown from seed with non-limiting nutrient supply at three day/night temperatures (11/6, 18/13 and 25/20°C) and two photoperiods (16 and 12 h). F. pratensis had a significantly lower relative growth rate than D. glomerata, mainly due to its lower specific leaf area and reduced nitrogen productivity. At high temperature, F. pratensis had a considerably lower root weight ratio than D. glomerata leading to substantially slower root growth. F. pratensis responded to a shorter photoperiod with an increase in the net assimilation rate, whereas D. glomerata responded with an increase in specific leaf area. The low competitive ability of F. pratensis compared to D. glomerata was mainly associated with its lower specific leaf area and nitrogen productivity. The stronger decline of its competitive ability during summer was probably related to the decreased allocation of dry matter to the roots at higher temperatures which leads to slower root growth compared to D. glomerata.

BACKGROUND: Strawberries (Fragaria × ananassa Duch.), the most popular berries grown and consumed all over the world, have a unique composition of bioactive compounds, including polyphenols that determine the quality, nutritional value and sensorial properties of those fruits. The study has provided data suggesting that there are links between the presence of bioactive compounds in strawberry leaves and the presence of those compounds in strawberry fruit. OBJECTIVE: Newly released and standard June-bearing strawberry cultivars (Fragaria × ananassa Duch.) were analysed with the aim of evaluating the content of health-related compounds in the fruit and leaves. RESULTS: The cultivars 'Clery' and the newly released 'Joly' are promising due to high levels of bioactive compounds in their fruit. The antioxidant capacity (TEAC) of the leaves was about 15 times higher than the TEAC of the fruit. Total phenolic compounds (TPC) were an important factor influencing the TEAC values of the fruit (r = 0.86). No significant correlation was found between TPC and TEAC in the leaves. The highest levels of bioactive compounds (TPC) were observed in the cultivars 'Selvik', 'Diana' and 'Clery'. In all of the analysed cultivars a high content of agrimoniin in the leaves was correlated with low TPC and TEAC values in the fruit. Additionally, the content of free ellagic acid in the leaves showed a good correlation with the cinnamic acid derivative and ferulic acid hexose derivative in the fruit. CONCLUSIONS: The measurement of the content of agrimoniin and free ellagic acid in strawberry leaves could help breeders to identify cultivars with a high antioxidant capacity and a high content of TPC, cinnamic acid derivatives and ferulic acid hexose derivatives in the fruit without waiting until fructification. The paper discusses this innovative conceptual approach to increasing breeding efficiency.

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Aims: The aim of the present study was to analyse the impact of different water regimes on the physiological and agronomical behavior of an aromatic white grapevine (cv. Arvine) by means of various levels of irrigation. The consequences of the plant water status were evaluated by carrying out a chemical (aromatic precursors) and sensorial analysis of the resulting wines.Methods and results: Adult vines of Vitis vinifera L. cv. Arvine grafted onto 5BB were subjected to different water regimes (various levels of irrigation) during the growing season. Physiological indicators were used to monitor the plant water status [pre-dawn leaf (ΨPD) and stem (ΨSTEM) water potentials and carbon isotope composition (d13C) in the must]. Gas exchange (net photosynthesis AN and transpiration E), stomatal conductance (gs), yield parameters, berry composition at harvest, analysis of potential grape aromatic properties (glycosyl-glucose G-G, precursor 3-mercaptohexanol P 3-MH) and the sensorial quality of wines were analysed over a period of 8 consecutive years (2009-2016) in the Agroscope experimental vineyard in Leytron under the relatively dry conditions of the Rhône valley in Wallis, Switzerland.In the non-irrigated vines, the progressively increasing water deficit observed over the season reduced the leaf gas exchange (AN and E) and gs. The intrinsic water use efficiency (WUEi, A/gs) increased over the season and was greater in the vines that had suffered water restriction than in the irrigated vines. The rise in WUEi was correlated with an increase in d13C in the must sugars at harvest. A decrease in plant vigor was observed in the water stressed vines over multiple years. Moderate to high water stress during fruit ripening lowered the contents of total and malic acidity in the musts and the content of yeast available nitrogen (YAN). On the other hand, contents in sugar and the aromatic precursor (P-3MH) in berries were not influenced by the vine water status. The G-G values for berries increased with rising water stress in the non-irrigated vines. The wines from the plants subjected to water stress and to yeast available nitrogen deficiency (non-irrigated vines during hot and dry seasons) had a less distinctive typicity, and developed a lower aromatic expression with a more bitter taste, than the wines from the non-stressed plants. Overall, and compared with the stressed vines, the organoleptic characteristics and quality of Arvine wines from vines which had not undergone restrictions in water and nitrogen during the growing season were appreciated more.Conclusions: The vine’s physiological behavior (leaf gas exchange, plant vigor) and agronomic parameters (yield, berry composition), together with the quality of white aromatic Arvine wines, were strongly influenced by vine water regimes during the growing season.Significance and impact of the study: Vine water status and must nitrogen contents are key factors in grape composition and in the sensorial quality of resulting aromatic white wines.