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Using Confocal Laser Scanning Microscopy (CLSM) for diagnosis of Terebrantia (Thysanoptera)
Full text linkAn Sendungen aus Drittländern in die EU werden häufig Thripse, Insekten der Ordnung Thysanoptera, beanstandet. Um zu entscheiden, ob phytosanitäre Maßnahmen erforderlich sind, oder ob eine pflanzengesundheitliche Risikoanalyse durchgeführt werden muss, ist eine rasche morphologische Artbestimmung erforderlich. Es werden hier zwei Anwendungen der konfokalen Laser-Scanning-Mikroskopie (CLSM) vorgestellt, die es ermöglichen, kleine Körperstrukturen von Thripsen zu visualisieren: (i) fluoreszierende Augen und (ii) Mikrotrichia. Diese innovativen Ansätze helfen, Thripsarten anhand ihres spezifischen Musters der Augenfluoreszenz, welches durch verschiedene Arten von Ommatidien (Einzelaugen) verursacht wird, zuverlässig zu diagnostizieren. Ein Screening nach potenziell artspezifischen Emissionsmustern könnte den detaillierten morphologischen Analysen vorausgehen. Im besten Fall könnte das Augenfluoreszenzmuster als diagnostisches Merkmal verwendet werden. In der Bestimmungsliteratur findet bisher lediglich die Größe und Anzahl pigmentierter Ommatidien Berücksichtigung.Da eine Probe im CLS-Mikroskop mit einem Laserstrahl gerastert wird, ist die Lichtstreuung minimal. Morphologisch charakteristische Merkmale geringer Größe wie bspw. Mikrotrichia können viel akkurater abgebildet werden. Somit könnten beide CLSM-Ansätze einen wertvollen Beitrag leisten, die herausfordernde morphologische Diagnose der winzig kleinen Thripse zu erleichtern.Thrips, insects from the order Thysanoptera, are often intercepted in consignments sent from third countries into the European Union. Rapid species identification is needed in order to quickly decide, whether phytosanitary measures are required or a pest risk analysis (PRA) has to be performed. Two applications of Confocal Laser Scanning Microscopy (CLSM) are presented here that allow visualizing subtle body structures of selected thrips: (i) fluorescent eyes and (ii) microtrichia. These innovative approaches support the reliable diagnosis of thrips species based on their specific pattern of eye fluorescence caused by different types of ommatidia (the units of a compound eye). A potential species-specific emission pattern provides a useful aid when screening samples prior to detailed morphological analysis. In the best case, the eye fluorescence pattern could be used as an additional diagnostic feature. Only size and number of pigmented ommatidia have yet been considered in existing identification keys.Since a sample is scanned with a laser beam in the CLS microscope, light scattering is minimal, which in turn means that small morphological structures such as microtrichia can be imaged much more accurately. Thus, both CLSM approaches could contribute significantly to facilitating the challenging morphological diagnosis of the tiny thrips
Preliminary insight into fungal diversity on imported cut greenery with reference to some potential implications for plant health
Full text linkGroße Mengen von Schnittgrün werden importiert um den wachsenden Bedarf der Europäischen Union auf dem Blumenmarkt zu decken. Bislang fehlen Informationen zu den mit diesem Schnittgrün assoziierten Organismen, somit liegen keine Grundlagendaten vor um das damit einhergehende phytosanitäre Risiko einzuschätzen. Die vorliegende Studie untersuchte importiertes Schnittgrün aus Drittstaaten nach Deutschland und zielt darauf ab, eine erste Evaluierung der Diversität und ökologischen Funktion von assoziierten Pilzen zu erlangen. Insgesamt wurden 1571 Pilzisolate aus 51 Proben aus 8 Ländern stammenden 27 Schnittgrünarten gewonnen. Nach Gruppierung in Morphotypen, wurden repräsentative Isolate mittels ITS Region der rDNA identifiziert und anschließend zu funktionalen Gruppen zugeordnet. Es wurden 3 Phyla, 8 Klassen, 39 Familien, 68 Gattungen und 112 Arten identifiziert. Auf unterschiedlichen taxonomischen Ebene (von Phylum bis Gattung), waren Ascomycota, Dothideomycetes, Sordariomycetes, Colletotrichum, Xylaria, Penicillium und Neopestalotiopsis die häufigsten Taxa. Die Zusammensetzung der Pilzgemeinschaft variiert nach Pflanzenart des Schnittgrüns, mit der höchsten Diversität aus Gaultheria shallon und Palme. Die Pilze wurden 7 trophischen und 16 funktionalen Gruppen zugeordnet, von denen die Kategorie der Pflanzenpathogene mit insgesamt 72 % die höchste relative Häufigkeit aufwies. Die stark überlappenden Pilzgemeinschaften von asymptomatischem und erkranktem Schnittgrün zeigten, dass eine Vielzahl von Pathogenen das Schnittgrün auch endophytisch oder asymptomatisch besiedeln. Insbesondere können die Ergebnisse dieser Studie als Ausgangspunkt für künftige tiefergreifende Untersuchungen zu pflanzengesundheitlichen Auswirkungen von Schnittgrünimporten dienen.Large quantities of cut greenery are imported into the European Union to meet the constantly increasing demand in the floristic market. So far, comprehensive information on organisms associated with this cut greenery is lacking and, thus, no basic data is available for evaluating the associated phytosanitary risk. The present study examined cut greenery imported from third countries to Germany with the aim to provide an initial evaluation on the diversity and ecological function of the associated fungi. Totally, 1571 fungal isolates were recovered from 51 samples of cut greenery belonging to 27 plant species originated from eight countries. After grouping into morphotypes, representative isolates were identified based on the ITS region of the rDNA and assigned to functional groups. Taxonomic identification delimited 3 phyla, 8 classes, 39 families, 68 genera and 112 species. At different taxonomical levels (from phyla to genus), Ascomycota, Dothideomycetes, Sordariomycetes, Colletotrichum, Xylaria, Penicillium and Neopestalotiopsis were the most frequent taxa. Fungal community composition varied with plant species, and the highest diversity was recovered from Gaultheria shallon and palm cut greenery. Fungi were assigned into 7 trophic modes and 16 functional groups of which the category of putative plant pathogens was highest with 72% relative abundance. Strong overlap in fungal communities of asymptomatic and diseased samples mostly consisting of plant pathogens indicated that various pathogens live endophytically or asymptomatically in cut greenery. Especially, the outcome of this work can be the baseline for further in-depth studies to assess the phytosanitary implications of cut greenery import
Potential of pesticide reduction and effects on pests, weeds, yield and net return in winter rye (Secale cereale L.)
Full text linkReducing the intensity of pesticide use is a societal and political issue. One way to realize this is to reduce the dose of applied pesticides. The impact of strict dose reductions on yield and net return in winter rye was examined in a longterm field trial at the experimental field of the Julius Kühn Institute in Dahnsdorf (Brandenburg) over a 13-year period (2004-2016). Pesticide treatments included a situation-related strategy (100% strategy) and two other strategies in which the doses were reduced by 25% and 50% compared to the 100% strategy. Treatment decisions were based on control thresholds in the 100% strategy. Fungal pathogens and weeds occurred in all years and had to be controlled. Insect pests were negligible. Averaged over all years, there was a significant difference of 4% in yield between the 100% strategy and the 50% strategy. In contrast, no differences were found in terms of net return. There was also no accumulation of weeds in the reduced strategies. This positive result is due to the close monitoring of the plots as well as the six-year crop rotation and shows that it is possible to reduce pesticide use in winter rye
Costs and benefits of preventive strategies to reduce pesticide use: Case studies on Integrated Pest Management in German arable farming
Full text linkPlant pests, diseases and weeds threaten agricultural crops and require control methods. However, the largely used pesticides are associated with undesirable effects on environment and health. To reduce pesticide use, Integrated Pest Management (IPM) offers a comprehensive toolbox. The two selected IPM strategies (1) wide crop rotation and (2) cultivation of pathogen resistant cultivars were analysed economically based on two different field trials. Crop rotation (long-term field trial at Dahnsdorf, Brandenburg, Germany, with a sixunit crop rotation) and pesticide reduction by 25% and 50% resulted in no decline in gross margins and thus profitability in silo maize, wheat (E- and A-quality), barley and rye. However, a 25% and 50% reduction in pesticides led to a decline in gross margins by -6.3% (-331 € ha-1) and -8.3% (-437 € ha-1) in potatoes. The use of pathogen resistant wheat cultivars and IPM based fungicide application (tested at five field sites across Germany) resulted in reduced fungicide applications and higher gross margins compared to the “non-IPM” strategy by about +45 to 70 € ha-1. Based on these findings, we conclude that preventive IPM strategies have a good potential to reduce pesticide use and are also economically viable for farmers
Exploring phenotypic plasticity leaf trait relationships in fungal-resistant grapevines using linear regression: Implications of the genotype environment interaction
Full text linkAccurate and non-destructive models for predicting leaf area (LA) are essential for monitoring vineyard growth and developing automated algorithms. In this study, we developed and compared the performance of eight linear regression models for predicting LA in eleven fungal-resistant grapevine genotypes. We also explored the phenotypic plasticity of leaf traits and their relationship with LA using kernel density estimation analysis. We found that genotype played a major role in defining leaf shape, and genotype-environment interaction was observed. The best models for LA estimation were identified for each genotype, and a leaf deformation index was proposed. Our results provide accurate and robust models for estimating LA in fungal-resistant grapevine genotypes and demonstrate the relationship between leaf traits and the environment. Additionally, we present a method for defining leaf asymmetry. Overall, this study contributes to the development of non-destructive and automated techniques for monitoring vineyard growth
Starch and green silver nanoparticles based functional nanocomposite films: New insights in fresh fruit packaging
Full text linkThis study uses sour cherries (Prunes census L.) pomace extract as a reducing agent to demonstrate the creation of silver nanoparticles (AgNPs) and preparation of starch film via blending glycerol, polyethylene glycol, and produced starch-AgNPs in different concentrations 1, 2, 3, and 4% of AgNPs with starch film as control. The prepared starch-Ag nanocomposite films were used for packaging strawberries at 4°C. Characteristics of the composite films included FTIR, XRD, SEM, and UV-vis spectroscopy. The composite films with 4% AgNPs showed a smooth surface, as the SEM results showed. Following blending with glycerol and AgNPs, the FTIR result changed the starch’s structure. After adding AgNPs, the composite film’s flexibility improved. The starch-Ag nanocomposite films demonstrated significant antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans. Weight loss was used to assess the impact of packing on the quality and shelf life of packed strawberries during storage, the effect time on pH, and microbial growth throughout a 14-day storage period. The results indicate that strawberry fruits may be kept fresher longer and their shelf life preserved with a 3% AgNPs starch-Ag nanocomposite. This is the first research that uses pulp extract from Prunus census L. to describe the production of AgNPs
Modification of skin anatomy and phenolic compounds of Tannat grapes along ripening by abscisic acid foliar applications
Full text linkThe ‘Tannat’ grapevine variety is known for its high polyphenolic content in grapes but low anthocyanin extractability. Secondary metabolite accumulation during ripening is influenced by a complex interplay of environmental factors and plant responses. While scientific literature indicates that abscisic acid (ABA) applications at veraison can modify the polyphenolic content of grapes, the effects can vary based on the dosage and climatic conditions. However, limited literature exists on the changes of grape skin anatomy in response to exogenous ABA applications during ripening. This study aimed to investigate the effects of ABA applications on ‘Tannat’ grapevines on the grape skin anatomy and polyphenolic compounds during ripening at two different locations. The results demonstrate that location was a key factor that significantly affected grape polyphenol content, under temperate-warm climate conditions and temperate, sub-humid nights (TSH) resulting in higher phenolic compound levels. Additionally, warm climates favored anthocyanin extractability. Grape skin cell typologies evolve differentially; while empty cells (type I) were independent of the climatic conditions, cells with anthocyanin accumulations (type II, III, IV and V) vary based on their polymerization degree in response to the climate conditions. ABA applications increased the total anthocyanin contents in the grapes harvested in the TSH location but did not affect their content in the WH site. The evolution of the anatomy of skin cells of ‘Tannat’ can help to better adjust ‘Tannat’ vineyard management in different viticulture regions (canopy management, exogenous ABA treatments, irrigation) and to improve wine production techniques (maceration days for anthocyanins extractability, aging of wines, etc.)
Unsealing, revitalizing and networking for more urban green – Report of the 13th Symposium Urban Green, Berlin, 7th and 8th November 2023
Full text linkZur Planung und Organisation von Städten ist diverse Infrastruktur erforderlich, die je nach Bereich in Funktionen unterteilt und unterschiedlich benannt wird. Zur grünen Infrastruktur gehört das Stadtgrün, das mit seinen Ökosystemleistungen vielfältige Funktionen in der Stadtlandschaft übernimmt. Die Gesamtheit des Stadtgrüns schließt sich als urbane grüne Infrastruktur zu einem Netzwerk aus naturnahen und gestalteten Flächen zusammen. Multifunktionalität, Nutzbarkeit, biologische Vielfalt und Ästhetik sind Ziele der Planung und Gestaltung der grünen Infrastruktur.Zur grauen Infrastruktur gehören Strukturen, die z. B. die Mobilität und Vernetzung in Städten ermöglichen. Um Städte klimaresilient und lebenswert zu gestalten, sind Maßnahmen zur Förderung der grünen Infrastruktur erforderlich. Dazu zählt die Entsiegelung von Flächen der grauen Infrastruktur, ihre Revitalisierung und geeignete Begrünung, sei es die Bepflanzung mit Bäumen, die Pflanzung von Stauden oder die Förderung der spontanen Vegetation. Diese Maßnahmen bewirken zusätzlich eine gezielte Vernetzung von Grünflächen und ihrer Qualifizierung für die grüne Infrastruktur. So lässt sich oft das vorhandene Netzwerk erweitern, verbessern und aufwerten.Vor diesem Hintergrund beschäftigte sich das 13. Fachsymposium Stadtgrün mit der Frage, wie man Flächen möglichst zielführend entsiegeln, revitalisieren und vernetzen sollte, um zu einem funktionsfähigen Stadtgrün beizutragen.Das 13. Fachsymposium fand als online übertragene Präsenzveranstaltung in Berlin statt. Die veranstaltenden Organisationen, namentlich in alphabetischer Reihenfolge, die Bundesanstalt für Landwirtschaft und Ernährung, das Bundesministerium für Ernährung und Landwirtschaft und das Julius Kühn-Institut bedanken sich bei den Vortragenden und den über 300 Teilnehmenden für eine sehr interessante und zukunftsweisende Tagung.Urban Green assumes diverse functions in the urban landscape through its ecosystem services. The entirety of urban greenery, regardless of the type of vegetation- and water-dominated area, forms an urban green infrastructure that integrates into a more or less connected network of natural and designed spaces. Multifunctionality, usability, biological diversity, and aesthetics are goals of planning and design.The unsealing of areas in the gray infrastructure, their revitalization, and appropriate greening, whether it be tree planting, the cultivation of perennials, or the promotion of spontaneous vegetation, are crucial measures for the deliberate connection of green spaces and their qualification for the green infrastructure. This often allows for the expansion, improvement, and enhancement of the existing network.Against this background, the 13th Urban Greenery Symposium addressed the question of how to effectively unseal, revitalize, and connect areas to contribute to a functional urban greenery. The renaturation of gray infrastructure areas should become part of the "new transformation culture" in cities, where nature-based solutions and dealing with constantly changing natural elements, as well as considering water conditions, are decisive design factors. Examples were derived to illustrate how plant habitats can be restored, and the possibility of networking new urban biotopes was discussed. The significant involvement of public and private actors and their gardens was reflected upon.The symposium was held in Berlin as an in-person event streamed online. The organizing entities, the Federal Ministry of Food and Agriculture, the Julius Kühn Institute, and the Federal Agency for Agriculture and Food, express their gratitude to the speakers and the over 300 participants for a very interesting and forward-looking conference
Effect of site conditions and fertilization treatments on morphological traits and mineral content of Aloe vera plants
Full text linkThe aim of this study was to investigate the effects of various fertilizer treatments on the morphological traits and mineral content of Aloe vera plants. The experiment was conducted in a greenhouse in Rabat, as well as two other fields in Skhirat and Sidi Bettach. The treatments including the ‘no application’, control F0 and three treatments which is compost (Organova) F1, compost combined with humus (Humivital) F2, and nitrogen (ammonitrate) 33% F3. The productivity of biomass was estimated based on the variables of morphological traits and mineral content. The effect of organic and inorganic fertilizers on the different variables of Aloe vera depends on the site. Significant effects were found for the most of the variables such as length, width, dry matter; ash content, manganese Mn, copper Cu, zinc Zn, calcium Ca, potassium K, carbon C, nitrogen N, sulfur S contents. Site effect was significant, with the higher values obtained for length, Width, Dry matter, Ash contents, Ca and N in Skhirat. Site effect was also significant for Mn and Cu in Sidi Bettach, and K in the greenhouse. The effect of the treatment F1 was significantly higher for the length and width of the leaves than F3 and the control F0, in addition F2 was significantly higher for the width of the leaves, nitrogen N and sulfur S contents