A comparison of bioactive compounds of strawberry fruit from Europe affected by genotype and latitude

Abstract

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.

Influence of growing conditions at different latitudes of Europe on strawberry growth performance, yield and quality

“…Korona and Clery) was negatively correlated to daily maximum temperature one or two weeks prior to harvest, respectively ( Table 8). The redder fruit surface in this study at lower latitudes are in agreement with the findings of Josuttis et al [16] who found in their study an increase of total anthocyanin in strawberry fruit from north to south. This increase of total anthocyanins was mainly caused by the increased content of pelargonidin 3-glucoside, which is one of the major anthocyanins giving strawberry fruit their red colour.…”

“…Fruit sampling and sample preparation are described in detail by Josuttis et al [16]. Briefly, at all sites, samples of 500 g of healthy fruit per replicate were collected twice in the middle of the harvest period.…”

Phenolic compounds profile of strawberry fruits of Charlotte cultivar

“…The studies conducted on 27 cultivars from Norway [9], 20 from Spain [10,11], 3 from Turkey [12], and 4 from Macedonia [13] revealed large differences in phenolics composition and antioxidant activity of strawberry fruits between cultivars. A recently published paper indicated that genotype was a major determining factor of bioactive components [14]. Currently the efforts of breeding programs are focused on developing new cultivars with enhanced flavour and preferably also improved levels of health-beneficial compounds [15,16].…”

Post‐flowering photoperiod has marked effects on fruit chemical composition in red raspberry (Rubus idaeus)

“…While the number of studies targeted at characterising enzymatic activity of these enzymes in soft‐fruit in response to different photoperiods is extremely limited, it is reasonable to surmise that photoperiod could be having an effect on sugar/organic acid ratio by modulation of the activity of such enzymes. However, a number of studies aimed at characterising the biochemical composition of strawberry to different latitudes have observed generally that plants grown at northern latitudes in Europe have significantly higher soluble sugar content (Davik et al ., ; Josuttis et al ., ). Such findings suggest the existence of a complex interplay of responses to a range of environmental factors, such as temperature and photoperiod, in the balance between sugar and organic acid content.…”

“…The fact that the daily light energy is also particularly high during the long summer days at high latitude further supports this likelihood. However, since such latitude‐related effects are confounded by a number of co‐varying environmental factors, it has proved difficult to sort out the causal relations under natural conditions (Jaakola & Hohtola, ; Josuttis et al ., ). In order to reduce these complications as much as possible, an experimental approach similar to the present one should be attempted, using pot‐grown long cane plants with high yield potential, and delay their distribution to a range of latitudinal growing sites until the plants have started flowering.…”