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Secondary and tertiary budbreak release is enhanced by extended dormancy chilling in \u27Shiraz\u27 grapevines
Get PDFLimited information exists regarding the dormancy of secondary and tertiary buds within the compound bud of grapevines. We were interested to evaluate how extended chilling duration would affect the budbreak percentage of all three bud orders within the compound bud. Dormant potted \u27Shiraz\u27 grapevines, with thirty retained buds per vine, were placed in a cool room at 4 °C over a 20-month period to extend dormancy. Vines were then systematically removed over five dates and placed in a controlled growth environment to assess budbreak percentages and cane tissue concentrations of abscisic acid and cytokinins. Budbreak was hastened by at least 13 d with vines receiving any extra chilling compared to no initial chilling. Furthermore, the firstly observed correlative inhibition of basal buds was apparently removed with chilling. Removal of correlative inhibition within the compound bud with increased chilling duration was also observed with the increases of secondary (doubles) and tertiary (triples) buds breaking simultaneously with the primary bud at each node. This resulted in 91 % of the nodes having two developing shoots and 56 % of the nodes presenting three developing shoots by the end of the experiment. Furthermore, a sigmoidal relationship between percent secondary buds and chilling duration was observed. Possible phytohormone connections were observed with the decline of ABA as secondary and tertiary buds broke at 414 d of chilling and depletion of the CKs, which coincided with the greatest rate of primary bud break after 242 d of chilling. Other possible involvement of ABA and Cis-type cytokinin interactions with secondary and tertiary bud dormancy is discussed. The results suggest future investigations into secondary and tertiary bud release within the grapevine using similar techniques may help to better understand the biochemical mechanisms associated with dormancy
Common garden versus common practice – Phenotypic changes in Trifolium pratense L. in response to repeated mowing
Get PDFPlants react to various biotic and abiotic factors by adjusting their growth pattern. This process, called phenotypic plasticity, can also be observed in the agronomical important fodder plant Trifolium pratense L. (red clover) which is grown worldwide for its high pro-tein content and soil improving ability. After cutting it changes its growth pattern due to phenotypic plasticity and initiates a second growth phase. Here, we analyze the regrowth dynamics of red clover in response to grazing or mowing by recording the plant’s architecture, leaf morphology, and growth performance in different cutting experiments. As previous studies were limited in the number of individuals and carried out via common garden experiments, we analyzed the regrowth reaction of T. pratense under standard agricul-tural field conditions. T. pratense forms smaller and rounder leaflets after repeated cutting, compensated by the production of more bio-mass. Nitrogen contents were subjected to seasonal changes, rather than by changes through cutting. As middle to late cut plants had higher regrowth capacities and regrew more biomass than early cut plants, an optimal time point for biomass harvest can be suggested to maximize the total yield of red clover biomass
Assessment of the profile of free amino acids and reducing sugars of cacao beans from local Cameroonian Trinitario (SNK varieties) and Forastero (TIKO varieties) using fermentation-like incubation
Get PDFThis study investigated the profile of cacao beans from the local Cameroonian Trinitario (SNK) and Forastero (TIKO) in terms of aroma precursors (amino acids and reducing sugars) through fermentation-like incubations. Treatments consisted of incubating beans in acetic acid, 100 mmol/L for two days followed by 200 mmol/L of acetic acid for three days (Treatment T1) and in 100 mmol/L of lactic acid for two days followed by 200 mmol/L of acetic acid for three days (Treatment T2). Both treatments resulted in an increase of free amino acids content by 1.5 - 2.5 times in SNK and TIKO varieties. The ratio of the hydrophobic amino acids over the rest of amino acids showed the preponderance of T1 on the hydrophobic amino acids released in TIKO while in the SNK, some varieties displayed the highest ratio in T2. Glucose and fructose content in TIKO and SNK beans increased 2 to 3 times during incubation. Galactose and raf-finose were found in unfermented beans. After incubation, raffinose was missing while at the same time a raise of galactose content could be seen. These results highlighted that acidification remains the factor inducing the releasing of free hydrophobic amino acids, the genotype being less involved
CO2 treatment increases glucosinolate hydrolysis products in two Arabidopsis thaliana accessions
Get PDFBrassicales include many vegetables of nutritional interest because the hydrolysis products of their phytochemicals, the glucosinolates, have health-promoting properties. So far, the impact of rising CO2 concentrations on glucosinolates and their hydrolysis is unclear. Applying a modified atmosphere, we exposed two Arabidopsis thaliana accessions that differ in their glucosinolate hydrolysis behavior, namely Hi-0 and Bur-0, to elevated CO2 concentrations. Glucosinolates and their hydrolysis products were analyzed using UHPLC-DAD-MS and GC-MS.
CO2 treatment increased indicators of primary production, such as biomass, leaf area and electron transport rate, and increased gluco-sinolate levels in Bur-0, but not Hi-0. Significantly, released glucosinolate hydrolysis product levels increased by up to 122% in Bur-0 due to increased epithionitrile formation. Likewise, in Hi-0 glucosinolate hydrolysis product levels increased after CO2 treatment by up to 67%, caused by enhanced nitrile and to some extent isothiocyanate formation. In addition, more alkenyl rather than alkyl glucosinolates were formed in Bur-0 under elevated CO2, thus changing the glucosinolate profile compositions. As CO2 treatment enhanced primary production but also overall glucosinolate hydrolysis pro-duct formation, it is conceivable to recycle excess CO2 by using it as supplement greenhouse gas to produce high-quality food
Direct injection on field sprayers for situation-appropriate and site-specific application
Get PDFBisher werden im praktischen Pflanzenschutz üblicherweise Tankmischungen eingesetzt, eine teilflächenspezifische Anwendung einzelner Mittel ist so unmöglich. Feldspritzgeräte mit Direkteinspeisung sind in der Lage, mehrere Pflanzenschutzmittel in einer Überfahrt unabhängig voneinander verzögerungsfrei und zielgenau zu applizieren. Direkteinspeisung ist eine notwendige Technik, um die teilflächenspezische Applikation mit getrennt dosierbaren Pflanzenschutzmitteln umzusetzen. Sie trägt damit zur umweltschonenden und nachhaltigeren Agrarproduktion bei. Nach der Entwicklung und Markteinführung eines Direkteinspeisungssystems ohne Verzögerungszeiten zur Teilflächenapplikation von Pflanzenschutzmitteln (Verbundprojekte ptBLE FKZ: 2815404010; 2815IP005) durch die Firma DAMMANN wurde das System im Praxiseinsatz für die teilflächenspezifische Applikation genutzt. Das System der Direkteinspeisung ermöglicht somit die sensor- und geodatengestützte Ausbringung von Pflanzenschutzmitteln.Up to now, tank mixtures have usually been used in practical crop protection, making a site-specific application of individual agents impossible. Field sprayers with direct injection are able to apply several crop protection agents in one pass, independently of each other, without delay and precisely. Direct injection is a necessary technique for implementing site-specific application with separately dosed crop protection agents. It thus contributes to environmentally friendly and more sustainable agricultural production. After the development and market launch of a direct injection system without delay times for the site-specific application of crop protection products (joint projects ptBLE FKZ: 2815404010; 2815IP005) by the company DAMMANN, the system was used in practice for site-specific application. The direct injection system thus enables the sensor- and geodata-supported application of plant protection products
Site-specific prognosis model for the spatial distribution of Fusarium crown rot
Get PDFDie teilflächenspezifische Applikation von Pflanzenschutzmitteln ermöglicht die variable Anpassung der Fungizidmenge an das räumliche Auftreten von Pflanzenkrankheiten im Schlag. Hierfür müssen jedoch geeignete Methoden zur Krankheitserkennung oder –prognose vorhanden sein. Deshalb wurde im Rahmen des Forschungsprojektes „AssSys“ (Anonym, 2021) ein teilflächenspezifisches Prognosemodell entwickelt, welches die relative räumliche Verteilung von Fusarium-Halmbasisverbräunung in Winterweizen prognostiziert. Hierbei werden anhand von topographischen Daten (Höhendaten, SAGA Wetness Index) drei Zonen unterschiedlicher Befallsgefährdung ausgewiesen. Zur Entwicklung und Evaluierung des teilflächenspezifischen Prognosemodells wurde in den Jahren 2011–2012 sowie 2018–2020 das räumliche Auftreten von Fusarium-Halmbasisverbräunung auf mehreren Untersuchungsflächen je Jahr bonitiert. Die Modellgüte wurde anhand der Koinzidenz zwischen bonitiertem und prognostiziertem Befallsniveau über die Untersuchungsflächen bestimmt. Diese variiert abhängig von der Datenquelle und der ausgewiesenen Zone zwischen 57 % und 80 %. Das teilflächenspezifische Prognosemodell ermöglicht somit die Identifizierung besonders sowie wenig vulnerabler Bereiche in Schlägen und wird prototypisch als Webservice via www.isip.de realisiert.Site-specific application of pesticides allows to adapt the application rate to the spatial distribution of plant disease(s) in fields. For this purpose, suitable procedures for disease detection or prognosis are necessary. Therefore, a site-specific prognosis model was developed in the research project “AssSys” (Anonym, 2021) to predict the relative spatial distribution of Fusarium crown rot in winter wheat. Based on topographic data (elevation data, SAGA Wetness Index) three zones of disease risk are differentiated. From 2011–2012 and 2018–2020 the spatial distribution of Fusarium crown rot was sampled in several study fields per year for model development and evaluation. Model quality was assessed as the coincidence between sampled and predicted disease level. It ranged from 57 % to 80 % given the data source and disease risk zone. In general, the site-specific prognosis model provides an opportunity to identify zones of high and low vulnerability in agronomic fields
Shelf-life study of osmodehydrated white cabbage packaged in modified atmosphere: A mathematical approach
Get PDFOsmotic treatment (OT) is a process applied for drying of fruits and vegetables where the hypertonic solution is osmotic medium. White cabbage (cultivar „Futoški“) shelf-life analysis was conducted after OT in three different hypertonic solutions: a mixture of commercial sucrose and NaCl (S1), a mixture of S1 and molasses in the ratio 1:1 (S2) and. pure sugar beet molasses (85.4% dry matter) (S3). After the OT, cabbage samples were packed in high barrier bags in the modified atmosphere packaging (MAP). The composition of two mix-tures of used gas (40:60/CO2:N2 and 80:20/CO2:N2) was imported into bags. The samples were analysed for L-ascorbic acid content, pH, acidity and a total number of microorganisms and sensorial attributes during 90 days of storage in a refrigerator at 4-8 °C in defined time intervals. During the 90-day storage in the MAP, microbiological analysis showed that the number of microorganisms decreased during the storage in the MAP. The highest retention of ascorbic acid (27.35%) was observed in OT cabbage dehydrated in pure molasses solution and 80:20/CO2:N2 gas mixture after 90 days of storage. Sensory analysis showed that osmodehydrated cabbage for 20 days in S1, and 45 days for OT cabbage in solutions S2 and S3 had acceptable consumable characteristics
Production of ornamental plants in Germany – will alternative plant protection strategies sustain production?
No full textCharakteristisch für den Zierpflanzenbau in Deutschland sind die Vielzahl an Kulturen und Produktionssystemen sowie die hohen Anforderungen an den Zierwert und die Transportfähigkeit der Erzeugnisse durch den Handel. Um diesen Anforderungen bei steigenden Kosten gerecht zu werden, wachsen, rationalisieren und automatisieren Betriebe.
Viele Jahre trugen Pflanzenschutzmittel dazu bei gesunde und vermarktungsfähige Pflanzen zu produzieren, denn bei der Vermarktung gilt Nulltoleranz für Schaderreger. Auf der anderen Seite schränkt der Handel seit Jahren die Palette verfügbarer Pflanzenschutzmittel über das gesetzliche Maß hinaus ein. Klassische Elemente des integrierten Pflanzenbaus wie Sortenwahl, Hygiene, Kulturführung oder technische Neuerungen, die im Folgenden beschrieben werden, stoßen hier aber an Grenzen. Seit Einführung der Indikationszulassung liegt die Zahl der Bekämpfungslücken in Sonderkulturen auf einem hohen und stabilen Niveau. Im geschützten Anbau wurde schon vor Jahren der biologische Pflanzenschutz mit Nützlingen eingeführt und wird erfolgreich praktiziert, solange für Notfälle nützlingsschonende Pflanzenschutzmittel zur Verfügung stehen. Aber viele gerade dieser Mittel überstehen den Prozess der Wiederzulassung nicht. Wie kann den Produzenten geholfen werden?
In diesem Übersichtsartikel wird die Situation im Zierpflanzenbau dargestellt sowie das Potenzial digitalisierter Hilfsmittel für das Monitoring von Schaderregern und zur Entscheidungshilfe für Pflanzenschutzanwendungen sowie alternativer Produkte, wie Biologika, Grundstoffe oder Biostimulantien diskutiert. Zuletzt werden Handlungsoptionen für die Beteiligten in der Produktion, im Handel und Politik zur Sicherung der Produktion beschrieben.Characteristic for ornamental production in Germany is the large number of different crops and production systems, as well as the high demands on ornamental value and the transportability of the products by retail markets. To meet these demands at increasing costs, farms are growing, rationalizing, and automating.
For many years, plant protection products were an important tool to produce healthy and marketable plants because zero-tolerance for pests applies to the marketing. On the other hand, the trade has for years restricted the range of available crop protection products beyond what is legal. However, classic elements of integrated crop management such as variety selection, hygiene, crop management, or technical innovations, which are described below, are reaching their limits here.Since the introduction of minor uses approvals, the number of control gaps in minor crops has remained at a high and stable level. In protected cultivation, therefore, biological plant protection with beneficial organisms has been introduced and is practiced successfully as long as selective plant protection products are available for emergencies. However, just many of these products do not survive the process of re-registration.
How can we support growers? In this review article, we discuss the current situation of ornamentals producing nurseries and the potential of digitized tools for pest monitoring and decision support for crop protection applications, as well as alternative products such as biologicals, basic substances, or biostimulants. Finally, options for action for stakeholders in production, trade, and politics to secure production are described
Journal of Cultivated Plants: A 100-year history
Get PDFDas Journal für Kulturpflanzen blickt auf eine 100-jährigeHistorie zurück. Angefangen als Nachrichtenblatt für den Deutschen Pflanzenschutzdienst hatte es von Beginn an die Aufgabe, die Pflanzenschutzdienststellen und die Landwirtschaft über aktuelle Entwicklungen der Pflanzenschutzforschung zu informieren und so zu einer Ertragssteigerung und damit besseren Versorgung der Bevölkerung mit Nahrungsmitteln beizutragen. Während seiner Geschichte erlebte die Zeitschrift häufigere Titeländerungen, was zum einen der durch Krieg und Teilung gekennzeichneten Historie Deutschlands und zum anderen der damit verbundenen dynamischen Entwicklung der deutschen Ressortforschung geschuldet ist. Seiner Rolle als Mittler zwischen Wissenschaft, Beratung und Praxis ist das Journal für Kulturpflanzen aber bis heute treu geblieben.The Journal of Cultivated Plants looks back on a 100-year history. Starting out as Nachrichtenblatt für den Deutschen Pflanzenschutzdienst, it had the task from the outset ofinforming plant protection services and agriculture about current developments in plant protection research and thus contributing to an increase in yields and a better supply of food for the population. During its history, the journal experienced more frequent title changes, due on the one hand to Germany\u27s history, which was marked by war and division, and on the other hand to the associated dynamic development of German departmental research. However, the Journal of Cultivated Plants has remained true to its role as a mediator between agricultural scientists, consultants and users
Analysis of changes in viticultural climatic indices in northwestern and western Iran
Get PDFClimate and climatic variables are very important factors in grape growth. Usually, temperature variables (maximum, average and minimum), as well as pre-cipitation variables (annual, monthly and daily), are used to determine the regional climate and to study the type and amount of climate change. Most of the viticultural climatic indices presented by researchers have been using the above variables. Northwestern and western regions of Iran are considered as the most important areas of grape cultivation with different climatic conditions in different parts that have led to the cultivation of grape cultivars. In this study, five temperature indices (Huglin, latitude-temperature, night cooling, temperature variability and Winkler) and two precipitation indices were investigated based on De Martonne and hydrothermal drought indices. Then, they were analyzed by Mann-Kendall method and Sen\u27s slope estimator index. The studies showed significant positive trends in Huglin, Winkler, night cooling and latitude-temperature indices, while the temperature variability index is significant only in a few stations. On the other hand, the indices related to drought and hydrothermal show no trend. However, some southern stations in the region showed a different trend in some indices. As a result, the trend of changes in temperature indices can lead to the expansion of cultivation of grape cultivars in the coming years, although the limitation of water resources will be a negative factor