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Transfer of perchlorate into different plant parts – Can perchlorate contaminations of soils explain perchlorate findings in vegetables and fruits?
Get PDFIm Jahr 2013 wurden in diversen Obst- und Gemüseprodukten aus verschiedenen Ländern hohe Perchlorat-Gehalte detektiert. Da Perchlorat auch in Düngemitteln nachgewiesen wurde und eine hohe Pflanzenverfügbarkeit aufweist, wurde angenommen, dass die Hauptquelle der Kontamination mineralische Dünger sein könnten. Prinzipiell sind aber auch andere Kontaminationspfade denkbar wie z.B. das Substrat, das Waschwasser im Aufbereitungsprozess der Gemüsebaukulturen oder die Behandlung, die z.T. durchgeführt wird, um die Lagerfähigkeit der Gemüseprodukte zu erhöhen.Um die Perchlorat-Aufnahme von Gemüsepflanzen und den Transfer in unterschiedliche Pflanzenorgane zu untersuchen, wurden in der vorliegenden Arbeit Gewächshausversuche mit verschiedenen Kulturen durchgeführt. Die Versuche wurden mit Spinat (Spinacia oleracea) und Mangold (Beta vulgaris) beispielhaft für Blattgemüse, Radieschen (Raphanus sativus) und Mairüben (Brassica rapa L. var. rapa) als Vertreter von Wurzelgemüse und Tomate (Solanum lycopersicum L.) als ein fruchtbildendes Gemüse durchgeführt. Perchlorat wurde dem Substrat in steigenden Konzentrationen von 0 – 5 – 10 – 100 – 500 μg ClO4-/Gefäß einmalig zu Vegetationsbeginn (2 bis 6-Blattstadium) in gelöster Form zugesetzt. Die untersuchten Pflanzenspezies haben annähernd die gesamte ihnen verabreichte Perchlorat-Menge aufgenommen und der höchste Anteil von 70–100% wurde in den Blättern der untersuchten Gemüsearten wiedergefunden. In Radieschenknollen und Mairüben wurden nur in den hohen Perchlorat-Stufen von 100 und 500 μg ClO4-/Gefäß Spuren von Perchlorat detektiert. In den Tomatenfrüchten wurde kein Perchlorat nachgewiesen, was darauf hindeutet, dass kein Perchlorat-Transfer von den Blättern in die Früchte erfolgt, wenn Perchlorat nur einmalig zu Vegetationsbeginn appliziert wird.Zusammenfassend kann festgestellt werden, dass Perchlorat-haltige Düngemittel durchaus kritisch im Einsatz bei Blattgemüse zu beurteilen sind, da näherungsweise das gesamte im Dünger enthaltene Perchlorat von den Pflanzen aufgenommen und in die Blätter transportiert wird. Für Wurzelgemüse und Gemüse, die eine längere Kulturdauer haben und Früchte ansetzen, ist das Risiko einer Perchlorat-Belastung als geringer zu beurteilen, wenn Perchlorat-haltige Dünger zu Vegetationsbeginn eingesetzt werden. Für die mehrmalige Applikation während des Vegetationsverlaufs kann aus den vorliegenden Daten kein Rückschluss gezogen werden.High perchlorate findings were reported in fruits and vegetables from different countries in 2013. It was speculated that mineral fertilizers were responsible for the contamination because perchlorate was detected in substantial amounts in some fertilizers and is generally available for plant uptake. In principle, other source such as the growth medium, washing water, contamination during packaging or treatment of products to increase shelf-life of fruits and vegetables are potential contamination sources as well.A greenhouse trial was conducted with different vegetables to investigate the perchlorate uptake and transfer between different plant organs. For this purpose, spinach (Spinacia oleracea) and Swiss chard (Beta vulgaris) were grown as leafy vegetables, radish (Raphanus sativus) and May turnip (Brassica rapa L. var. rapa) as root vegetables and tomato (Solanum lycopersicum L.) as a fruit-bearing crop. Perchlorate was added to the substrate in concentrations of 0 – 5 – 10 – 100 – 500 μg ClO4-/pot to the young plants (two to six leaf stage). The investigated species took up almost the applied perchlorate and the highest proportion of 70–100% was detected in leaves. In the bulbs of radish and May turnip only at the higher level of 100 or 500 μg ClO4-/pot low concentrations of perchlorate could be detected. In tomato fruits no perchlorate was detected indicating that no transfer from leaves to fruits occurred, when perchlorate was applied in one dose at the beginning of the experiment. It can be concluded that the majority of perchlorate contained in fertilizers will be taken up by plants and will be stored mainly in leaves. Therefore, leafy vegetables have a high risk to be contaminated by perchlorate while the edible parts of bulb vegetables and fruits show a lower risk to be contaminated when perchlorate was applied at the beginning of vegetative growth. No conclusions are possible if perchlorate-containing fertilizers are applied regularly over the whole vegetation period
Global warming allows two grape crops a year, with about two months apart in ripening dates and with very different grape composition - The forcing vine regrowth to obtain two crops a year
Get PDFWith the aim of delaying the ripening of grapes by around two months, a technique has been proposed based on forcing vine regrowth (Gu et al. 2012, Martínez de Toda et al. 2019). It is a bold method to fight against climate warming that could be only developed in really warm viticultural regions. It consists in shortening the growing shoots to several nodes with the aim of forcing vine regrowth; in order to force budbreak, shoot regrowth, and cropping, the source of inhibition needs to be eliminated and to this end, lateral shoots, leaves, and primary clusters, if they exist, are removed.But the main drawback of the forcing vine regrowth technique is loss of yield. In order to avoid this loss of yield and not to eliminate the primary clusters already formed in the main shoots, it is possible to force the development of buds of the fifth and sixth nodes, but maintaining the clusters of the main shoots. In this way, the yield of the forced buds would be added to the normal or primary yield of the shoots. The experiences carried out with \u27Grenache\u27, \u27Tempranillo\u27 and \u27Maturana Tinta\u27 varieties in La Rioja (Spain) are presented
The impact of temperature on \u27Pinot Noir\u27 berry and wine quality in a steeply sloping cool climate vineyard in South Australia
Get PDFViticulture is particularly sensitive to climate change, as temperature is critical to the two key concepts of terroir and vintage. Vitis vinifera L. \u27Pinot Noir\u27 is known to not grow well in hot climates. A trial was run over two years in a commercial vineyard in the Adelaide Hills, South Australia, to determine the impact of higher temperatures on the \u27Pinot Noir\u27 grape and wine colour. A factorial experiment combining two sources of variation in temperature was established: three positions on a steep vineyard slope, and two thermal treatments: unheated control and heated with passive open-top transparent chambers. Elevated temperature decoupled sugars and anthocyanins in grape berries, with the heated treatment grapes producing a lower anthocyanin concentration for the same concentration of total soluble solids. Temperature effects were less defined for small batches of wines prepared from these grapes, with the wines from heated vines having higher total phenolics, and perhaps consequently lower CIELab b* values (i.e., less blue pigmentation/anthocyanins). The study provides a unique insight into temperature gradients on a steeply sloping site and the effects on colour development of \u27Pinot Noir\u27 grape berries and wine
Medicinal plants and their secondary metabolites − State of the art and trends in breeding, analytics and use in feed supplementation− with special focus on German chamomile
Get PDFPlants in ecology interact with their biotic and abiotic environment. Means of interactions, and thereby crucial for the survival of the species, are secondary plant metabolites. Exploration of the plants’ metabolism in action and reaction to their environment, the formation and release of secondary plant metabolites in specific (stress) situations and their functions as attractants, defence or protection agents gives us the chance to exploit the knowledge for human purposes. The purpose of medicinal use of these metabolites turns the bearing plants into medicinal plants. Health promoting, disease preventing and other favourable effects make these plants and their extracts valuable as dietary and feed additives. This review covers some current aspects of conventional breeding, particularly of German chamomile, of phytochemical analytics and of use of medicinal plants in feed supplementation. The main three groups of functional plant metabolites terpenes, polyphenols and alkaloids are treated. Outlook in research, in challenging analytical questions and in effective product development is provided, outlining current trends in production of secondary plant metabolites and demands on the market
Book Review - The Pomegranate – Botany, Production and Uses
Get PDFThe pomegranate (Punica granatum L., family: Punicaceae) is one of the oldest known edible fruits and is associated with the ancient civilizations of the Middle East. This is the first comprehensive book covering the botany, production, processing, health and industrial uses of the pomegranate. The cultivation of this fruit for fresh consumption, juice production and medicinal purposes has expanded more than tenfold over the past 20 years. Presenting a review of pomegranate growing, from a scientific and horticultural perspective, this book provides information on how to increase yields and improve short- and medium-term grower profitability and sustainability. It covers: practices to mitigate pests, diseases and abiotic stresses; yield-based nutrition management; cultural practices for cultivars with horticultural traits such as earliness, high yield, improved taste, soft seeds, disease resistance, and low splitting and sunscald rates; increasing crop diversity to aid crop security; and composition, food uses and medicinal applications.
This book provides a valuable support not only for farmers and for people involved in the pomegranate industry but it can be recommended without any reservation to plant breeders, plant physiologists, food technologists and chemists to obtain comprehensive information on the current state of knowledge of this important fruit species.
The book starts by providing a detailed overview about archaeology, history and symbolism of pomegranate plants. Subsequent sections deal mainly with the taxonomy, propagation and breeding of pomegranates. Furthermore, the environmental requirements, different harvest methods, various plant diseases and their individual management, postharvest biology, optimal storage conditions and bioactive compounds are discussed in detail on a high scientific level. A number of scientific articles are listed in each annex of the 18 sections, allowing readers to obtain more detailed information on the individual topics.
Ali Sarkhosh, Alimohammad M. Yavari, Zabihollah Zamani, The Pomegranate – Botany, Production and Uses, CAB International 2020, 578 pages including bibliographical references and index, price: 176,00 €, ISBN: 978-1-78924-076-4 (hardcover)
Influence of processed Halyomorpha halys bugs on the aroma and taste of \u27Chardonnay\u27 and \u27Merlot\u27 musts and wines
Get PDFNative to East Asia, the invasive brown marmorated stink bug (Halyomorpha halys) was accidentally introduced into Switzerland around 2004 and is now spreading all over Europe. This pentatomid is highly polyphagous and attacks vegetables, field and tree crops as well as soft fruits. Moreover, all development stages of H. halys are found in vineyards, suggesting that grapevine is also a host plant for this insect. Nonetheless, its actual effects on European wine production is unclear. As such, we studied the impact of processed H. halys on the aroma and taste of grape musts and wines. We artificially contaminated \u27Chardonnay\u27 and \u27Merlot\u27 grapes with up to ten H. halys nymphs and adults per kg grapes directly before the vintage was crushed. In the freshly pressed must, the addition of 1 living bug/kg grapes did not affect the olfactory sensation of the \u27Chardonnay\u27 juice. However, the aroma and taste of \u27Chardonnay\u27 and \u27Merlot\u27 musts contaminated with 3 to 10 H. halys individuals/kg grapes could be distinguished from the uncontaminated control juices and were perceived as vegetal and woody. Yet after bottling, the different wines with 0 to 10 H. halys individuals/kg grapes could no longer be differentiated from each other in 2-out-of-5 discrimination tests. Amongst 17 rated organoleptic descriptors to characterise the sensory profile of the four \u27Chardonnay\u27 wines, only two showed significant differences; the colour intensity increased and wines’ finesse decreased with the number of added bugs. For the three \u27Merlot\u27 wines, none of the 21 organoleptic descriptors of the sensory profiles differed significantly. In addition, winegrowers did not dislike H. halys contaminated \u27Chardonnay\u27 and \u27Merlot\u27 wines compared to their uncontaminated controls one year after bottling. It therefore seems that the molecules responsible for the off-flavours in contaminated musts volatilise to a large part during the fermentation process. Our results consequently indicate that a contamination of the vintage with H. halys has the potential to alter the quality of grape musts and potentially grape juices but that there is little risk for influencing the taste of processed wines. Nonetheless, we recommend monitoring the development of H. halys in vineyards in order to anticipate quantitative and qualitative problems at harvest
Improved optical phenotyping of the grape berry surface using light-separation and automated RGB image analysis
Get PDFGrape resilience towards Botrytis cinerea (B. cinerea) infections (Botrytis bunch rot) is an important concern of breeders and growers. Beside grape bunch architecture, berry surface characteristics like berry bloom (epicuticular wax) as well as thickness and permeability of the berry cuticle represent further promising physical barriers to increase resilience towards Botrytis bunch rot. In previous studies, two efficient sensor-based phenotyping methods were developed to evaluate both berry surface traits fast and objectively: (1) light-separated RGB (red-green-blue) image analysis to determine the distribution of epicuticular wax on the berry surface; and (2) electrical impedance characteristics of the grape berry cuticle based on point measurements. The present proof-of-concept study aiming at the evaluation of light-separated RGB images for both phenotyping applications, phenotyping wax distribution pattern and berry cuticle impedance values. Within the selected grapevine varieties like \u27Riesling\u27, \u27Sauvignon Blanc\u27 or \u27Calardis Blanc\u27 five contributions were achieved: (1) Both phenotyping approaches were fused into one prototypic unified phenotyping method achieving a wax detection accuracy of 98.6 % and a prediction of electrical impedance with an accuracy of 95 %. (2) Both traits are derived using only light-separated images of the grapevine berries. (3) The improved method allows the detection and quantification of additional surface traits of the grape berry surface such as lenticels (punctual lignification) and the berry stem that are also known as being able to affect the grape susceptibility towards Botrytis. (4) The improved image analysis tools are further integrated into a comprehensive workbench allowing end-users, like breeders to combine phenotyping experiments with transparent data management offering valuable services like visualizations, indexing, etc. (5) Annotation work is supported by a sophisticated annotation tool of the image analysis workbench. The usage of light-separated images enables fast and non-invasive phenotyping of different optical berry surface characteristics, which saves time-consuming labor and additionally allows the reuse of the berry samples for subsequent investigations, e.g. Botrytis infection studies