Apple trees (Malus domestica Borkh.) develop an abundance of flowers and shed the majority of fruitlets in the first developmental stages. In this study the process of abscission was monitored in cultivar ‘Golden Delicious’ and linked with the position of fruitlets in the cluster, focusing on differences among central or king flower/fruit (K1), flowers/fruit nearest to the king flower (lower on the peduncle; L2) and flowers/fruit located at different positions near the base of the peduncle (L3-L6). Individual clusters consisted of 3–7 flowers the most frequent were clusters with 5 flowers. Abscission was biphasic with the first peak 29 days after full bloom (DAFB) and the second peak 48 DAFB. At the end of the abscission process approx. 70% of all fruitlets shredded. Fruitlets at the central position (K1) were frequently unaffected by this process and developed to fruit in 70% of the analyzed clusters. The ratio between subsisting and shedded fruitlets was the opposite for lateral positions in the cluster; approx. 70% of fruitlets abscised in the clusters with 4/5 flowers. No significant differences in the level of abscission have been observed between the lateral positions in the cluster (L2-L6). A tendency to abscission has been detected for L2 position (lateral fruitlet nearest to the king flower) in clusters consisting of 6 flowers. This was further confirmed at harvest. Fruit from the lateral position nearest K1 were smaller and firmer in comparison to K1, L3 and L4. This demonstrates the obvious dominance of the central fruit in comparison to lateral fruit, especially those nearest to the king fruit. This is particularly evident in clusters with many flowers.
COBISS.SI-ID: 8222073
Traditional elderflower beverages are very popular due to their pleasing taste and pro-health properties. Phenolics were quantified in three elderflower extracts (methanolic extraction and two water extracts prepared as fresh drinks according to local recipes) with HPLC-MS. Chromatographic patterns of methanolic and water extracts were quite similar; however, content levels of individual compounds differed between the two extraction solvents. Two feruloylquinic acids and two p-coumaroylcaffeoylquinic acids and different flavonol glycosides have been identified in elderflowers for the first time. Hydroxycinnamic acids and flavonol glycosides were the major phenolic constituents in elderflowers. Methanolic extract contained higher levels of all phenolic groups compared to water-extracted samples. The yield of elderflower extracts depended on extract solution and time of extraction. Elderflower beverages were characterized by high total phenolic content (91.09 to 746.63 mg AE/L). The results confirmed that elderflower beverages (sabesa, syrup) should be recommended as a good source of phenolics in human diet.
COBISS.SI-ID: 8100729
There are no defined maturity parameters for berry fruit which often results in harvesting and marketing of inedible, immature or over ripe berries. In the present study the changes in quality characteristics of different white-, red-, and black-currant cultivars as well as gooseberry and jostaberry fruit were investigated at three maturity stages. Colour parameters, berry juice pH level and the content of sugars, organic acids and phenolic compounds have been evaluated. A total of 65 different phenolic compounds were detected by HPLC–PDA/MS. The results indicate that, during the last 2–4 weeks of fruit ripening, significant changes occur in colour parameters, primary and secondary metabolites and radical scavenging activity. The results suggest that the average content of specific phenolic groups and sugars/acids ratio can be used as a simple and reliable maturity index for optimisation of harvest time.
COBISS.SI-ID: 8056697
Apples (Malus domestica Borkh.) are one ofthe most studied fruits, however when we look closely we have inadequate information on how the metabolites are distributed inside the fruit. We performed a study of twelve different sampling positions in apple, six on each side of the fruit (sunlit and shaded). We sampled two cultivars: ‘Jonagold’ and ‘Granny Smith’. Samples along the equatorial plane of the fruit varied more than those along the height of the fruit. What grabbed our attention was the flesh sample in the vascular region with higher content of phenolic compounds, especially dihydrochalcones in comparison to other flesh sampling positions. Also the distribution of sugars and organic acids varied between positions. The results can help with more accurate sampling of apple fruits and are the basis for better understanding of metabolite distribution in apple fruit
COBISS.SI-ID: 8553337
A common technological practice in Brussels sprout (Brassica oleracea L. var. gemmifera) production is the removal of apical plant section a few weeks before harvest in order to promote the development of auxiliary buds (sprouts) and ensure higher yields. It is well known that this measure positively influences the size of the sprouts but until now no study has focused on the effect of decapitation on the content of primary and secondary metabolites in Brussels sprout. Plants were decapitated one month before harvest and sprouts were sampled from three sections along the stem (basal, middle, top) of each plant. The sprouts were harvested, weighted and chemically analyzed. The content of individual sugars was assessed by HPLC and the content of individual phenolics and glucosinolates by HPLC-MS. Significant interactions between the decapitation and different stem sections were detected in the weight of the sprouts, as well as in their sugar levels. The highest sugar content was determined in basal sprouts collected from decapitated plants. Conversely, basal sprouts from non-decapitated plants were characterized by the lowest sugar content. No interaction between the decapitation and stem sections was detected in the level of phenolics or glucosinolates. Decapitation promoted the accumulation of all glucosinolates and hydroxycinnamic acids. Moreover, the content of glucosinolates and flavonoids was always highest in the sprouts from the top stem section.
COBISS.SI-ID: 8494457