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A study on the influence of planting distances on the growth, productivity and fruit quality of dwarf apple trees in a 15- to 18-year-old orchard was carried out at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry. Trees of the apple (Malus × domestica Borkh) cultivar 'Auksis' on rootstock P 60 were planted at distances of 3 × 1.5, 3 × 1.25, 3 × 1.00 m and 3 × 0.75 m. With increasing density of fruit trees, singletree growth, generative development and yield were significantly reduced. The opposite results were obtained when these parameters were evaluated per unit area. Yield and fruit quality measurements were made at two canopy heights: 0-1.5 and 1.5-2.5 m. In the upper part of the fruit tree canopy, fruit average weight and diameter were higher, while the colour was more intense and less dependent on the planting density of fruit trees. In the lower part of the canopy, fruit quality was inferior and with increasing fruit tree density it further deteriorated. Planting distances had a significant effect on the accumulation of sugar, soluble solids and dry matter content: greater planting distances resulted in increased sugar content from 10.97% to 11.90%, soluble solids - from 12.30% to 13.17% and dry matter content - from 13.80% to 14.80%. Conversely, higher accumulation of phenolic and triterpenic compounds in apple fruits was found with decreasing planting distances. A significant increase of phenolic compounds from 2.91 up to 4.03 mg g-1 DW (dry weight) was recorded at the upper part of the canopy, while an increase of triterpens from 12.9 up to 16.07 mg g-1 DW - at the lower part of the canopy. The best productivity and fruit quality of 'Auksis' apple trees on P 60 rootstock at the full bearing stage were obtained, when fruit trees had been spaced at 3 × 1.25 m. [ABSTRACT FROM AUTHOR]

Regardless of the numerous investigations of secondary metabolites, the impact of new growing technologies or individual technological means on fruit internal quality, particularly triterpene concentration in apple fruits has not been studied yet. Apple-tree (Malus × domestica Borkh.) growing technologies and geographical location of the growing site had clear effect on triterpene concentration in apple fruits. The effect of crop load, fruit location in apple-tree canopy, planting distance, apple-tree vegetative growth regulation and geographical location on triterpene content in apples was evaluated in 2015 and 2016. Four triterpenic compounds: corosolic, betulinic, oleonolic and ursolic acids, were quantified in apple peel. Triterpene accumulation in apple fruits was directly correlated with crop load, where 17% more total triterpenes were found at the highest crop load (12 fruits cm-2 trunk cross-sectional area (TCSA)) in comparison to the lowest crop load (4 fruits cm-2 TCSA). Higher concentration of triterpenes was found in the fruits harvested from the inner canopy of the apple-tree. Apple-tree growth regulation affected the synthesis of triterpenes - trunk incision decreased the amount of total triterpenes by 16% compared to the control and by 26% compared to summer pruning. Also, a trend of higher accumulation of triterpenes in fruits was found along with decreasing apple-tree planting distances. Colder climate and shorter vegetation period resulted in significantly higher contents of triterpenes in the fruits of cultivar 'Auksis' in Lithuania and Estonia compared to the fruits grown in Poland. The same trend, yet insignificant, was noticed for the cultivar 'Ligol'. [ABSTRACT FROM AUTHOR]

The research objective was determination of ripening attributes of intact tomato (Lycopersicon esculentum Mill.) cv. 'Rutuliai' using near infrared (NIR) spectroscopy and reference analysis. Tomatoes were picked at six different ripening stages in order to evaluate the correlation between data obtained by near infrared spectra and physicalchemical analyses and how the quality parameters change during ripening. Primarily, spectroscopic measurements were followed by chemical analyses. NIR spectroscopy measurements and reference analyses showed that tomato fruit had lost skin and flesh firmness during the ripening processes and there were no big differences between the methods used for the determination of dry matter and soluble solids (°Brix) and the obtained results varied slightly. The obtained results of dry matter, soluble solids content (°Brix) and fruit skin and flesh firmness were presented as simple linear regression between NIR spectroscopy and reference analyses. A high correlation between NIR spectroscopy and reference analyses of dry matter was established and this correlation, expressed by regression coefficient, reached 0.9089. Regression coefficient between NIR spectroscopy and reference analyses of soluble solids was 0.815. Meanwhile, the highest correlation was detected for tomato fruit skin and flesh firmness and regression coefficient, respectively, reached 0.9119 and 0.9624. Hence the near infrared calibration has the potential to estimate the physical-chemical properties of tomato fruit according to their infrared spectra. [ABSTRACT FROM AUTHOR]

The lycopene content in food may be increased by thermal and mechanical processing. Food processing is beneficial because it disrupts food matrices facilitating the release and solubilisation of lycopene resulting in increased carotenoid bioavailability for the formation of cis-isomers. A lycopene-rich and β-carotene oil-based system was used in this study. High-performance liquid chromatography (HPLC) and colour coordinates analyses were employed to analyse lycopene, its cis-isomers and β-carotene stability of the following sample set after 28 days of storage: fridge temperature at 1 ± 1°C in absence of light (FT dark), ambient temperature at 20 ± 1°C in natural light with different day and night illumination (AT light), ambient temperature at 20 ± 1°C in absence of light (AT dark), thermostatically controlled temperature at 37 ± 1°C in absence of light (TT dark) and thermostatically controlled temperature at 37 ± 1°C in UV irradiation (TT UV). The control sample in our study was lycopene enriched oil stored in the dark at 1 ± 1°C on day zero (0). The aim of this study was to create lycopene-enriched oil from tomato to investigate its stability and to prepare the recommendations to consumers for the storage conditions of this functional food. The results indicated that the trans-lycopene amount changed from 76.6% to 61.0% at ambient temperature (AT light and AT dark sample), and from 76.6% to 46.8% (TT dark) and 44.4% (TT UV) at 37 ± 1°C. According to our investigation, the highest percentage of 5-cis-lycopene isomer in all samples was found after 28 days of storage. The TT UV samples had the most colour changes. Vegetable oil enriched with lycopene from tomatoes is a high quality food product that can supplement daily diet and enhance absorption of lycopene from the intestine. [ABSTRACT FROM AUTHOR]

The specific HPLC analytical procedure was developed and validated for the determination of phenolic compounds in pear samples of different popular cultivars “Conference,” “Concordia,” “Grabova,” and “Patten.” HPLC mobile phase consisted of 0.05% (v/v) trifluoroacetic acid in water and 100% (v/v) acetonitrile. The HPLC method was used to identify and confirm the specificity of 8 analytes: chlorogenic acid, rutin, hyperoside, isoquercitrin, isorhamnetin rutinoside, quercitrin, quercitrin malonyl glucoside, and isorhamnetin glucoside. Repeatability % RSD did not exceed 3.87%, and intermediate precision did not exceed 4.63%. The total content of phenolic compounds varied from 0.51±0.001 mg/g (cv. “Concordia”) to 1.11±0.013 mg/g (cv. “Patten”). Chlorogenic acid was the major component in all the tested pear cultivars. The highest amount of chlorogenic acid (0.69±0.033 mg/g) was found in pear samples of the cultivar “Grabova,” and the highest amount of flavonol compounds (1.11±0.013 mg/g) was found in pear samples of the cultivar “Concordia.” [ABSTRACT FROM AUTHOR]

Simple Summary: Mosquitoes are the carrier of pathogens that cause common human diseases such as malaria, Dengue, Chikungunya, yellow fever, Zika, and West Nile. The use of chemical and biological insecticides is among the key control tools for reducing mosquito populations at different life stages (i.e., eggs, larvae, pupae, and adults). The weaknesses of these tools, especially those with chemicals, are the high cost of production, and their negative effects on other beneficial organisms such as bees and water-dwelling invasive species. Thus, researchers and academics are searching for new safe and environmentally friendly forms of insecticides. Of late, green synthesized plant-based metallic nanoparticles have attracted great interest as an alternative to traditional insecticides. Typically using metal salts in combination with aqueous plant extracts, the synthesis of these nanoparticles is eco-friendly and relatively cheap. This review aims to report on the currently available knowledge on the development of green synthesized metallic nanoparticles and their performance as repellent, ovicidal, larvicidal, pupicidal, and adulticidal agents against different mosquito species. Mosquitoes act as vectors of pathogens that cause most life-threatening diseases, such as malaria, Dengue, Chikungunya, Yellow fever, Zika, West Nile, Lymphatic filariasis, etc. To reduce the transmission of these mosquito-borne diseases in humans, several chemical, biological, mechanical, and pharmaceutical methods of control are used. However, these different strategies are facing important and timely challenges that include the rapid spread of highly invasive mosquitoes worldwide, the development of resistance in several mosquito species, and the recent outbreaks of novel arthropod-borne viruses (e.g., Dengue, Rift Valley fever, tick-borne encephalitis, West Nile, yellow fever, etc.). Therefore, the development of novel and effective methods of control is urgently needed to manage mosquito vectors. Adapting the principles of nanobiotechnology to mosquito vector control is one of the current approaches. As a single-step, eco-friendly, and biodegradable method that does not require the use of toxic chemicals, the green synthesis of nanoparticles using active toxic agents from plant extracts available since ancient times exhibits antagonistic responses and broad-spectrum target-specific activities against different species of vector mosquitoes. In this article, the current state of knowledge on the different mosquito control strategies in general, and on repellent and mosquitocidal plant-mediated synthesis of nanoparticles in particular, has been reviewed. By doing so, this review may open new doors for research on mosquito-borne diseases. [ABSTRACT FROM AUTHOR]

The trial was carried out at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry in 2013-2015. Cv. 'Auksis' was tested on 12 rootstocks: B.396, B.9, M.9, M.26, P 22, P 59, P 61, P 62, P 66, P 67, PB.4, and Pure 1. Accumulation of phenolic compounds depended on fruit yield and average fruit weight. On average, significantly lower concentration among rootstocks occurred when apple trees had abundant yield and fruits were smaller. On average chlorogenic acid constituted 50% and total procyanidins 28% of total phenols in 'Auksis' fruits. Flavonoid concentration most depended on rootstock and the highest variation was recorded. More than 50% difference occurred between the highest total flavonoid concentration in apples on PB.4 and the lowest on M.9 rootstocks. Low variability of total procyanidin concentration among rootstocks was observed. Differences between the highest and lowest concentration was 15%. Total concentration of phenolic compounds differed among rootstocks by 29-35% depending on the year. Differences in accumulation of phenolic compounds depended on rootstock genotype but not on yield or fruit weight. PB.4 and P 67 rootstocks had the highest, and M.9, P 62 and M.26 had the lowest concentration of total phenol in 'Auksis' fruits. [ABSTRACT FROM AUTHOR]

A new technique for the rapid detection and analysis of triterpenic compounds in apple extracts using HPLC was developed and validated. The main advantage of this technique is the short duration of the analysis - this makes this technique superior to others currently applied for the routine HPLC analysis of triterpenic compounds. The developed, optimized, and validated technique was used for the evaluation of triterpenic compounds in samples of different cultivars of apples, their peels, and flesh. In total, four triterpenic compounds were isolated and identified. Ursolic acid was the dominant compound in all the tested apple samples. The highest amounts of triterpenic compounds were detected in the peels of the 'Lodel' apple cultivar, and thus apples of this cultivar may be potentially useful for the isolation of individual compounds and the production of functional food and dietary supplements. [ABSTRACT FROM AUTHOR]

Nutrient uptake and transport depend on the root system of a tree. Various apple rootstock genotypes may interact fruit tree nutrition. The effect of apple (Malus × domestica Borkh.) rootstocks (M.9, M.26, B.396, P22, P59, P61, P62, P66, P67, Pure 1 and PB.4) on the mineral nutrition of leaf and fruit was studied in 2013-2015. The leaf and fruit mineral concentration for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and leaf mineral content for copper (Cu), zinc (Zn), iron (Fe), manganese (Mn) and boron (B) were measured. Apple trees on semi-dwarf M.26 and dwarf P67 rootstocks accumulated more minerals in leaves and fruits. The highest negative deviation from optimal nutrient content was detected in leaves from trees on super-dwarf rootstock P59. Red-leaved rootstocks accumulated significantly more Ca in leaves and fruits of scion cultivar and determined significantly lower K, N and Mg ratios to Ca. Rootstock vigour had impact only on leaf Ca and Mg. More dwarfing rootstocks determined higher content of Ca and lower content of Mg. More vigorous rootstocks had positive effect on fruit K and P, while dwarfing on K, N and Mg ratios to Ca. Based on rootstock selectivity to accumulate certain minerals, by choosing the right rootstock genotype we can create orchards tolerant of unfavourable soil conditions. [ABSTRACT FROM AUTHOR]

The methods recently applied for decontamination of fruits and vegetables are not always efficient, human and ecologically friendly. In this context, photosensitization might serve as really promising tool. Obtained data indicated that Botrytis spp. was susceptible to photosensitization and its growth inhibited 14 % and reduced 18 % rotten strawberries. The following evaluation of shelf life of treated strawberries indicated some extension in comparison with control ones. The examination of nutritional quality of treated strawberries revealed that total antioxidant activity, amount of phenols and anthocyanins did not change in comparison with control. No effects on berry color were observed, just a slight reduction (10 %) of fruit firmness found in treated ones. In conclusion, photosensitization has potential as bio-fungicide, since inactivates Botrytis spp. on the surface of strawberry without impact on their nutritional properties or visual quality. [ABSTRACT FROM AUTHOR]

One of the most important postharvest diseases of strawberry and raspberry is grey mould, caused by Botrytis cinerea Pers.: Fr. New non-chemical food safety technologies reducing berry rots and extending storage time were tested. Photosensitization is an innovative method for inhibition of pathogens in berry and is based on the interaction of light (λ = 400 nm, 20 mW cm-2) and photoactive compound (chlorophyllin derivative). The aim of this study was to evaluate the effect of the chlorophyllin-based photosensitization on the reduction of grey mould (B. cinerea) in postharvest strawberry and raspberry fruits. The berries were soaked in a treatment solution for 1 hour and then exposed to prototype (light) for 30 minutes. The obtained data indicated that chlorophyllin derivative inhibited grey mould infection on fruits. The infection of B. cinerea in strawberries after a 6-day storage decreased by 8% and in raspberries after 1-day storage it decreased by 3%. The chlorophyllin had no impact on the visual quality and nutritional properties of strawberries and raspberries. [ABSTRACT FROM AUTHOR]

The study was done with the two peppermint (Mentha × piperita L.) cultivars - 'Krasnodarskaja' and 'Peppermint', whose leaves were dried using different methods. Investigation of fresh and dried herbs was carried out according to the biochemistry and technology methods. Essential oil was extracted using the hydro distillation method, the amount of chlorophyll a and b was measured spectrophotometrically according to the Vernon method. The highest content of essential oil (0.77%) and chlorophyll (1.69%) was found in the cv. 'Peppermint'. Chlorophyll a to b ratio was different in the fresh peppermint leaves: in the cv. 'Peppermint' it was 1.35 and in the cv. 'Krasnodarskaja' - 1.44. Peppermint leaves were dried using active ventilation, convection, infrared, vacuum, microwave, and sublimation methods. The quality of dried herbs depended on the properties of plants and drying techniques. The highest content of essential oil (0.64-0.68% of dry mass) was found in the variously dried peppermint leaves of the cv. 'Krasnodarskaja'. The lowest content of essential oil (0.08% and 0.065% of dry mass) was determined in microwave dried herbs. The highest content of chlorophyll was found in the lyophilized peppermint leaves (715.0 mg 100 g-1 of dry mass) of the cv. 'Peppermint'. Regardless of the drying method, significant differences between the ratio of chlorophyll a to b were observed in the dried herbs of the cv. 'Krasnodarskaja'. The fresh and dried peppermint samples of the cv. 'Peppermint' had the lowest brightness L* value (from 22.61 to 35.24) and the lowest yellowness b* values (from 9.35 to 17.00). The biggest changes in greenness a* value were in microwave dried peppermint leaves. [ABSTRACT FROM AUTHOR]