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Tomatoes are an important source of benefcial phytochemicals, which act as antioxidants. These include ascorbic acid, phenolic compounds, carotenoids, and tocopherols. The concentration of anti-oxidants is infuenced, among others, by abiotic stress factors like nutritional status. Potassium (K) is a macronutrient, which is essential for several physiological functions in plants -- for example, translocation of assimilates, activation of enzymes, maintenance of turgescence, and stomata regulation. This study aims to investigate the effect of increasing K fertilization on the concentration of anti-oxidants in cocktail tomatoes. Therefore, two tomato cultivars (Primavera and Resi) grown in an outdoor pot experiment were ferti- lized with increasing K doses for two consecutive years. It has been confrmed that antioxidants in tomato fruit can be affected by the K regime, but it is also shown that other factors may reduce or even reverse those effects when cultivation takes place in an uncontrolled outdoor environment. The most consistent K fertilization effects were found for naringenin, p-coumaric acid, and caffeic acid. However, the enrichment of tomatoes with antioxidants by K fertilization is cultivarependent and therefore general statements should be avoided. [ABSTRACT FROM AUTHOR]

This study was conducted to improve the knowledge of molecular processes involved in the interaction between Fusarium graminearum and emmer in the course of grain ripening. Emmer plants were artificially inoculated with a F. graminearum spore suspension at anthesis. In the course of grain ripening from milk ripe to plant death stage, grains at four phenological growth stages were collected for analysis. The infection degree was evaluated based on the F. graminearum DNA content in emmer grain infolding tissues (glumes and rachis). For proteome analysis the albumin and globulin fractions of emmer grains, consisting of proteins with various functions related to the development and stress response, were analysed regarding the changes due to Fusarium infection by two-dimensional gel electrophoresis. Altogether, forty-three proteins affected by infection were identified by mass spectrometry. Enzymes detoxifying reactive oxygen species were regulated at all developmental stages. In the early stage of grain development, the abundance of proteins related to stress response, such as 2-Cys peroxiredoxin, a chitinase, a xylanase inhibitor and a spermidine synthase was increased. During later stage of grain development, the abundance of stress-related proteins, such as chitinases, heat shock proteins and an a-amylase inhibitor-like protein, decreased. During all ripening stages, but especially during medium milk stage (BBCH 75) and soft dough stage (BBCH 85), the abundance of proteins related to carbon metabolism, starch and protein biosynthesis as well as photosynthesis increased due to F. graminearum infection. At the plant death stage (BBCH 97) the abundance of only two proteins related to metabolism decreased. [ABSTRACT FROM AUTHOR]

BACKGROUND Wines rich in biogenic amines can cause adverse health effects to the consumer. Being nitrogen-containing substances, the amount of amines in wines might be strongly influenced by the rate of nitrogen fertiliser application during grape production. The aim of this work was to evaluate the effect of nitrogen fertilisation in the vineyard on the formation of biogenic amines in musts and wines. RESULTS In a field experiment which compared unfertilised and fertilised (60 and 150 kg N ha−1) vines over two separate years, the total amine concentrations in must and wine increased. The latter was due to an increase of individual amines such as ethylamine, histamine, isopentylamine, phenylethylamine and spermidine in the musts and wines with the nitrogen application. Furthermore, the fermentation process increased the concentration of histamine and ethylamine in most of the treatments, while spermidine, spermine and isopentylamine concentrations generally decreased. Throughout both vintages, the concentrations of tyramine and histamine of the investigated musts and wines never reached detrimental levels to the health of non-allergenic people. CONCLUSIONS Nitrogen fertilisation has a significant effect on amines formation in musts and wines. Furthermore, during fermentation, ethylamine and histamine increased while other amines were presumably serving as N sources during fermentation. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The demand for organically grown tomatoes has rapidly increased on the consumer side. However, there is a lack of tomato cultivars suitable for organic farming that are both high yielding and of superior fruit quality. In the present study, the variation in plant growth and fruit quality of tomato cultivars was assessed to identify the traits associated with higher yield and improved fruit quality. Sixty tomato cultivars, cocktail and salad tomatoes, were grown under organic low-input conditions in 2015 and a subset of 20 cultivars for further evaluation in 2016. The results revealed a high variability among 60 cultivars in all 28 traits that were observed. Salad cultivars that have been selected for intensive indoor cultivation exhibited the highest yield components. A cross-year evaluation of the 20 cultivars showed that salad cultivars had 10-70% lower fruit quality including minerals, dry matter, total soluble solids, and total phenolic compounds (TPC), but 10-60% higher fruit yield and leaf minerals than cocktail cultivars. Cocktail cultivars with improved yield performance were derived from organic breeding. Depending on the cultivar, there was a trade-off between fruit yield and fruit quality. Interestingly, salad cultivars with high magnesium (Mg) concentration in the leaves also contained high Mg concentration in the fruits. Moreover, fruit Mg correlated positively with titratable acidity and TPC of the salad cultivars, as well as with fruit phosphorus, potassium, and sulfur in both cocktail and salad cultivars. The results indicate the contribution of Mg in improving flavor, health related-compound and nutritional quality of tomato fruits. This information provides a novel path for further studies to improve plant-available Mg in organic tomato production to enhance fruit mineral concentration and fruit quality. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.) fruit contain several health beneficial antioxidants [1]. Their contents can be greatly influenced by abiotic factors such as light, temperature, or the nutritional status [2]. The macronutrient potassium (K) is essential for several physiological functions in plants, e. g. translocation of assimilates, activation of enzymes, maintenance of turgescence, and stomata regulation. The aim of the study was to investigate the impact of increasing K fertilization on the antioxidants ascorbic acid, phenolic compounds, carotenoids, and tocopherols in tomatoes. Three cocktail tomato cultivars (Primavera, Resi, and Yellow Submarine) raised in an outdoor pot experiment were treated with five rising K doses in the first study year 2014. In 2015, Primavera and Resi were selected for a subsequent experiment using the lowest and highest K doses. In this experiment, the lipophilic antioxidants were additionally measured in three different tomato ripening stages. Increasing levels of K fertilization distinctly affected the contents of antioxidants in cocktail tomatoes (Table 1). However, most of the effects were not consistent across all three cultivars and the two study years. In 2014, K fertilization level positively correlated (p≤0.05 or 0.01) with ascorbic acid and γ-tocopherol in Resi and with p-coumaric acid in Primavera, while significant negative correlations were observed for narigenin and ß-carotene in Primavera and for β-tocopherol and δ-tocopherol in Yellow Submarine. In contrast, significant positive correlations between K fertilization level and ascorbic acid, p-coumaric acid and caffeic acid were demonstrated for both, Primavera and Resi, in 2015. As opposed to 2014, the tocopherols in Resi and Primavera negatively correlated with increasing K fertilization. The only antioxidant that consistently showed positive correlations with increasing K doses across cultivars and study years was p-coumaric acid. In summary, the content of plant antioxidants in cocktail tomatoes cultivated outdoors can be positively or negatively affected by K fertilization. However, other abiotic factors, such as variation in light and temperature may impact or even inverse those effects [3,4]. [ABSTRACT FROM AUTHOR]

Aroma of fruit is a key indicator to depict the quality of fruit flavor and is likely to play an important role in determining the perception and acceptability of products by consumers [1,2]. Flavor has obviously been targeted as a secondary breeding goal in recent decades [3]. Studies reveal that tomatoes grown under organic conditions positively increase the consumer preference [4]. Therefore, it is necessary for plant breeders who are developing cultivars for organic production to select also for better flavor characteristics. Sixty indeterminate cultivars which differ mainly in terms of fruit weight, year of cultivar release and fruit color were grown in an outdoor organic low-input system in a temperate climate. The diversity of volatile organic compounds (VOCs), taste-related primary metabolites, and sensory properties of ripe tomatoes consisting of 27 cocktail and 33 salad tomato cultivars released between 1880 and 2015 from conventional, organic or unknown breeding programs, were investigated at two different harvest dates in 2015. The volatile compounds of tomato fruits were semi-quantified by GC-FID and tentatively identified by GC-MS. Isolation of volatiles were performed through automated headspace solid-phase microextraction (HS-SPME). A non-targeted data analysis (pattern recognition) was used. The evaluation of the cultivars from the two harvest dates exhibited a wide range of variation for all studied traits, with the exception of a few VOCs. Cultivar × harvest date interaction had no significant effect on TA (titratable acidity), TSS (total soluble solid), or overall acceptability but influenced most of the studied VOCs. Further examination was focused on total of 25 VOCs: 7 aldehydes, 5 ketones, 7 alcohols, 4 aliphatic acids, 1 ester and 1 sulfur-containing compound. The main compounds with the highest value in relative concentration in the headspace of tomato fruits include hexanal, 6-me-5-heptene-2-one, (E)-2-hexenal, octanal, 1- hexanol, etc., of which aldehydes are the most abundant volatile group. Variation in all studied traits like fruit type, harvest time, or fruit color was observed, and the discriminative variables characterizing the fruit types were revealed. Principal component analysis differentiated cocktail and salad types with a higher contribution of taste related-primary metabolites (TSS and TA), sensory attributes (sweetness, tomato typical-aroma, and sourness) and phenyl ethyl alcohol, the latter is a discriminative key compound to distinguish cocktail from the salad type. The observed correlations among the metabolites give cues for their biosynthesis pathway. The presence of VOCs such as (Z)-3-hexen-1-ol, phenyl ethyl alcohol, and benzyl alcohol had effect on the perception of ‘sweetness' and ‘tomato typical-aroma'. Therefore, the present findings should provide a preliminary knowledge for cultivar selection in breeding programs that perform better in flavor and are suitable for organic low-input production systems. [ABSTRACT FROM AUTHOR]

Being a staple food potatoes are grown in many countries with a world-wide production of 380 Mio tonnes in 2014 [1]. In Germany the per capita consumption of potatoes is about 56.8 kg in the financial year 2015/2016 with a share of 60% of processed potatoes [2] such as fried products (e.g. French fries). Industrial processing of French fries includes several steps like quality control of raw material, blanching, par-frying and freezing [3]. End-frying as the last preparation step is mainly done in canteens or at home. In fried products the heatinduced contaminant acrylamide can be formed via the Maillard reaction depending on the amount of the precursors reducing sugars (glucose, fructose) and asparagine [4]. Different NIRS applications have been tested for potatoes during the last decades. Good predictions of the dry matter and starch content have been established by measuring theraw grounded tuber [5]. Potato cultivars used for processing of French fries usually contain a high amount of dry matter that mainly consists of starch. Due to their low concentration, reducing sugars in the raw tuber (3-24 mmol/kg) and likewise, the acrylamide in the deep fat fried product are minor components [4]. NIRS-based predictions of reducing sugars in the raw material would be an advantage in the quality control of industrial French fries processing [5]. However, acceptable predictions for such minor components are hardly reachable [5,6]. Nonetheless, in potato breeding process less exact predictions could be a useful complementation in the phenotyping of new breeding lines. Within a current project (DEPOLA, starting 2017) we try to develop a NIRS model to be usedas a valid screening tool in identifying potato genotypes with a low acrylamide potential. To perform the trial, a set of 185 genotypes from German and Turkish breeding programs is grown in both countries of contrasting climatic conditions. The total sample number will reach at the projects end 1600 including field replications, several locations (three per country) and different storage treatments. Yet, a subset of 96 samples is analyzed. The quality parameters that were used for model development are dry matter, starch, glucose, fructose, sucrose, colour (L*a*b* values) and acrylamide. NIR measurement was repeated twice for each sample and a wavelength range of about 400-2500 nm was monitored with a FOSS XDS NIR spectrophotometer. Most quality parameters show a high variation within the data set, especially for acrylamide but also for the colour (a* value) and the glucose content, which is a basic requirement. Taking into account the size of the sample set a cross validation was performed. Besides, using non-treated spectra that seem to be well suited for the dry matter content (R² of calibration and prediction of 0.97 and 0.96, respectively), the first and second derivatives were used to model the prediction of the minor components. For glucose the R² of calibration and prediction were 0.85 and 0.59 when using the first derivative. By using the second derivative for acrylamide the R² of calibration and prediction were 0.91 and 0.41. The mathematical pre-treatments were able to improve the model indices. Even though the data set was small, it indicates capabilities of NIR technique as a screening tool for breeding purposes. Satisfactory information should be taken from a larger data set that we will gain by the end of the project in 2020. [ABSTRACT FROM AUTHOR]

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There is evidence that potassium (K) fertilization enhances the yield of medium and large-sized tomato cultivars. Many authors observed positive effects of K fertilization on fruit color, texture, total soluble solids (TSS) and titratable acids (TA) [3, 6]. The market for small-sized cocktail tomatoes is currently growing due to their preferable taste [5] which is positively related to increasing levels of TSS and TA [1, 2, 4]. We hypothesize, that K improves yield and quality of cocktail tomatoes. In order to test our assumption, we carried out pot experiments in two consecutive years. In a pot (6 L) experiment, three cocktail tomato cultivars (Primavera, Resi and Yellow Submarine) were fertilized with five K levels (3.1, 6.3, 9.4, 12.5 and 18.7 g K/pot applied in total over 19 weeks) to find out ideal dosages for well and deficient fertilized plants. Interestingly, the K effect on yield and most quality parameters was highly cultivar specific: while Primavera and Yellow Submarine reached a yield increase of more than 100% from the lowest to the highest K dose, no response of Resi was observed. In contrast to Primavera and Yellow Submarine, Resi showed only weak K fertilization effects on fruit quality aspects. Therefore, in a second experiment we grew the cultivars Primavera and Resi with two K doses (deficient and well-fertilized). In a third treatment, we interrupted K fertilization in order to induce a response in the cv. Resi to a sudden shortage of K. In contrast to Primavera, Resi showed no yield response to K fertilization like in the first experiment. The low yielding cv. Resi seemed to be more K efficient compared to Primavera. We conclude that the effect of K on yield and quality of cocktail tomatoes depends on the cultivar. [ABSTRACT FROM AUTHOR]

This article discusses two studies that explore methods for reducing acrylamide levels in processed potatoes. The first study used New Genomic Techniques (NGTs) to edit the genetic makeup of a potato variety called Lady Rosetta, resulting in lower levels of acrylamide. The second study focused on identifying specific genetic variations in potato alleles that can reduce acrylamide content in processed products. Both studies offer potential solutions for reducing acrylamide without the use of harmful chemicals. The data supporting these findings can be found in the supplementary material of the article. [Extracted from the article]

Breeding goals of potatoes for deep-frying purposes include high starch contents, good suitability for long-term storage, and low tendency to form reducing sugars as acrylamide precursors. Due to the extensive number of samples, an accurate analysis of acrylamide in French fries and its precursors in tubers is difficult to implement in the breeding process. Therefore, this study aimed to evaluate the suitability of NIRS measurements after minimal sample processing for the prediction of reducing sugar contents in the tubers or acrylamide contents in French fries. An external validation with more than 650 samples consisting of 194 potato genotypes resulted in a prediction accuracy of 51 % for acrylamide and 76 % for reducing sugar content. RPD values of less than 1.5 for acrylamide and between 1.64 and 2.23 for reducing sugar prediction rendered low medium to medium model quality. Nevertheless, acrylamide prediction models based on NIRS measurement of mashed tubers categorised over 80 % of unknown samples correctly as being below or above the European threshold value, indicating suitability as rapid test procedure in the breeding process., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier Ltd.)

Cocoa beans are produced all across the humid tropics under different environmental conditions provided by the region but also by the season and the type of production system. Agroforestry systems compared to monocultures buffer climate extremes and therefore provide a less stressful environment for the understory cocoa, especially under seasonally varying conditions. We measured the element concentration as well as abiotic stress indicators (polyamines and total phenolic content) in beans derived from five different production systems comparing monocultures and agroforestry systems and from two harvesting seasons. Concentrations of N, Mg, S, Fe, Mn, Na, and Zn were higher in beans produced in agroforestry systems with high stem density and leaf area index. In the dry season, the N, Fe, and Cu concentration of the beans increased. The total phenolic content increased with proceeding of the dry season while other abiotic stress indicators like spermine decreased, implying an effect of the water availability on the chemical composition of the beans. Agroforestry systems did not buffer the variability of stress indicators over the seasons compared to monocultures. The effect of environmental growing conditions on bean chemical composition was not strong but can contribute to variations in cocoa bean quality.

Pollination improves the yield of most crop species and contributes to one-third of global crop production, but comprehensive benefits including crop quality are still unknown. Hence, pollination is underestimated by international policies, which is particularly alarming in times of agricultural intensification and diminishing pollination services. In this study, exclusion experiments with strawberries showed bee pollination to improve fruit quality, quantity and market value compared with wind and self-pollination. Bee-pollinated fruits were heavier, had less malformations and reached higher commercial grades. They had increased redness and reduced sugar-acid-ratios and were firmer, thus improving the commercially important shelf life. Longer shelf life reduced fruit loss by at least 11%. This is accounting for 0.32 billion US$ of the 1.44 billion US$ provided by bee pollination to the total value of 2.90 billion US$ made with strawberry selling in the European Union 2009. The fruit quality and yield effects are driven by the pollination-mediated production of hormonal growth regulators, which occur in several pollination-dependent crops. Thus, our comprehensive findings should be transferable to a wide range of crops and demonstrate bee pollination to be a hitherto underestimated but vital and economically important determinant of fruit quality.