Ulvi Moor

Effect of Selenium Treatment on Mineral Nutrition, Bulb Size, and Antioxidant Properties of Garlic (Allium sativum L.)

Foliar selenium (Se) treatment of garlic at concentrations of 10, 50, and 100 μg of Se/mL was carried out in open field conditions in 2008 and 2009 in Estonia. Bulb weight and yield structure, content of total Se, S, N, P, K, Ca, and Mg, ascorbic acid content (AAC), pungency, total phenolics, and total antioxidant capacity (TAC) were determined. The highest level of Se decreased total S, K, and Ca in both years; no negative impact on bulb weight was observed. In 2009 Se10 treatment had significantly more bulbs with the largest diameter compared to the other treatments. In 2008, the AAC was decreased by Se50 and the content of total phenolics by all Se treatments; however, TAC was increased. Foliar Se fertilization of garlic at rates of 10-50 μg of Se/mL can be recommended to increase the number of large bulbs and increase bulb antioxidant capacity.

Metabolic profiling discriminates between strawberry (Fragaria × ananassa Duch.) cultivars grown in Finland or Estonia

Metabolic profiling analysis with LC-ESI-QTOF-MS was utilized to separate and identify 186 putative major metabolites demonstrating significantly different levels in 15 strawberry cultivars grown in Finland or Estonia. Principal component analysis showed close clustering of genetically related samples grown in Estonia, and hierarchical cluster analyses highlighted differences and similarities in their metabolic profiles driving separation between cultivars with specific metabolic phenotypes. Phenolic acids, flavonoids, flavan-3-ol derivatives, terpenes, and many types of glycosidically bound aroma and flavor precursors showed clear variation between strawberry cultivars. These cultivar-specific differences in the levels of major potentially bioactive phytochemicals in strawberries suggests that cultivar selection is essential for breeding strawberry cultivars with optimal phytochemical compositions contributing to possible functional properties and good cultivation and sensory qualities.

EFFECT OF FERTILIZATION ON THE LOWBUSH BLUEBERRY PRODUCTIVITY AND FRUIT COMPOSITION IN PEAT SOIL

The aim of the research was to study the effect of different fertilizers on the productivity and fruit composition of lowbush blueberry (Vaccinum angustifolium Ait.) cultivated in abandoned peat pits. The experiment was established in 2000 with two-year-old seedlings on cutover peat field in North Estonia (59° 9′N and 25° 19′E). The soil type in the experimental area was Fibric-Dystric Histosol and the cutover peat layer was more than 1.0 m thick. Total yield, fruit weight, fruit titratable acidity, soluble solids, ascorbic acid and anthocyanin content were determined. The effect of fertilization on the ascorbic acid content was different in 2004–2005. Liming increased fruit anthocyanin content in both years when nitrogen (N), phosphorus (P), and potassium (K) were applied at the rate of 0.8, 2.0 and 7.2 g m−1, respectively. Application of the same fertilizer rate without liming, produced sweeter fruits. Thus, research results indicated that fertilization of lowbush blueberries on cutover peat fields is necessary and in order to get high quality yield, the right fertilization rate is important.

Composition of commercially produced organic and conventional strawberries

Purpose – The purpose of this study was to determine differences in taste-related and bioactive compounds of organically (OR) and conventionally (CONV) cultivated commercially produced strawberries (Fragaria × ananassa Duch.). Addresses the question if the consumers buying OR strawberries are likely to purchase fruits with better taste and richer in bioactive compounds than those buying CONV fruits. Design/methodology/approach – Only information commonly available to the consumers [cultivar, quality class, product origin (country) and eco-labelling], was considered in selecting experimental material. “Polka” strawberries from 14 farms (7 OR and 7 CONV) from South Estonia were used for analyses. Findings – No evidence was found that OR strawberries contain more bioactive compounds or have higher soluble solids content and titratable acids ratio (associated with better taste) compared to CONV strawberries. There were significant differences in content of total phenolics, anthocyanins, ascorbic acid, vitamin...

The productivity and fruit quality of the arctic bramble (Rubus arcticus ssp. Arcticus) and hybrid arctic bramble (Rubus arcticus ssp. arcticus×Rubus arcticus ssp. stellatus)

Abstract The fruit biochemical content and productivity of arctic bramble (Rubus arcticus ssp. arcticus) and hybrid arctic bramble (R. arcticus ssp. arcticus×R. arcticus ssp. stellatus) cultivars were investigated during three experimental years (2001–2003) in field conditions. Rows of experimental plants were alternated with rows of raspberry (Rubus idaeus L.). Finnish cultivars together with a strain from Estonian nature (E1) and Finnish and Swedish hybrid cultivars were planted in rows that were covered with plastic mulch. The cultivars and strain were planted in rows turning in order to secure the best conditions for pollination. The following combinations were used: E1 + ‘Susanna’; E1 + ‘Mespi’; E1 + ‘Pima’; ‘Astra’ + ‘Aura’; ‘Astra’ + ‘Anna’; ‘Anna’ + ‘Beata’. Yield and biochemical content were different between variants consisting of two cultivars. Significantly higher yield parameters such as fruit weight, number of drupelets, and productivity were observed from the hybrid cultivars ‘Astra’ + ‘Aura’. Combinations with arctic bramble cultivars did not have a significant difference in yield, thus all tested cultivars are suitable for growing in combination with Estonian clone. Hybrid arctic bramble fruits in cultivar combinations of ‘Astra’ + ‘Anna’ showed the highest titratable acid (TA) content. E1 and ‘Susanna’, in combinations with arctic bramble, had higher soluble solids and ascorbic acid content, but TA and SS/TA did not show significant differences. The darkest (L*) and reddest (+a*) juice was found in fruit of hybrid cultivars combinations; those combinations with ‘Astra’ produced the darker juice colouring.