7850 research outputs found
Sort by
Analysis of active ingredient deposition after application of plant protection products in bioassays and practice – the requirement for a realistic evaluation of the sensitivity of pests of horticultural crops
Full text linkDie Forderungen und Ansprüche des Handels und der Konsumenten nach Pflanzen ohne Besatz durch Schaderreger und/oder von ihnen induzierten Symptomen führen im Gartenbau zu häufig wiederholten Bekämpfungsmaßnahmen in engen Applikationsfolgen. Die Umsetzung der zum Schutz des Verbrauchers und der Umwelt geforderten Reduzierung der Risiken von zugelassenen Pflanzenschutzmitteln (PSM) führte dazu, dass in der Praxis oft keine ausreichend weite Wirkstoffpalette für einen Wirkstoffwechsel vorhanden ist. Selektion auf Resistenzen von Schaderregern und Minderwirkungen sind die Folge. Im Gartenbau wird zunehmend über Minderwirkungen von Insektiziden und Akariziden berichtet, ohne dass ein zweifelsfreier Nachweis der Ursachen erfolgte. In einem Konsortium aus Vertretern mehrerer öffentlicher und privater Einrichtungen wurden deshalb Methoden zur Bestimmung der Sensitivität/Resistenz etabliert, um das Wissen über Resistenzen gegen Insektizide und Akarizide im deutschen Gartenbau zu verbessern. Die von der IRAC (Insecticide Resistance Action Committee) empfohlenen und damit international anerkannten Methoden wurden ebenfalls berücksichtigt.In diesem Beitrag wird berichtet, wieviel Wirkstoff bei verschiedenen, auch international validierten Resistenztests im Labor (Biotests) auf den behandelten Oberflächen tatsächlich abgelagert wird. Die mit der Kryo-Rasterelektronenmikroskopie (Kryo-REM) sichtbar gemachte Diversität der Mikromorphologie von Pflanzenoberflächen gibt Anlass das zu überprüfen. Am Beispiel von Pflanzenschutzmittelapplikationen in Rosenkulturen wird gezeigt, dass auch die Evaluation der Wirkstoffbeläge in der gartenbaulichen Praxis ein wesentlicher Baustein für die Beurteilung der Sensitivität der Schaderreger ist. Die Analyse der Wirkstoffe ermöglicht die Validierung der Applikation von PSM in Vorbereitung der Biotests und die Bewertung der Wirkungen von PSM-Anwendungen im Labor und in der Praxis.Ein zweiter Beitrag, der sich mit der Sensitivität ausgewählter Schaderreger des Gartenbaus gegenüber verschiedenen PSM beschäftigt, wird an anderer Stelle veröffentlicht werden.In horticulture, the demands and requirements of the trade and consumers for pest-free or symptom-free plants often lead to repeated control measures in close application sequences. The implementation of the reduction in the risks of authorised plant protection products (PPPs) required to protect consumers and the environment has, in practice, often led to a lack of a sufficiently wide range of active substances for a rotation of active substances. This development results in a selection for pests resistant to insecticides and reduced efficacy of insecticides. In horticulture, reports of reduced effects of insecticides and acaricides are increasing, although there is no conclusive proof. A consortium of representatives from several public and private institutions has therefore applied methods for determining sensitivity/resistance to improve knowledge of resistance to insecticides and acaricides in German horticulture. The methods recommended by the IRAC and, thus, internationally accepted were also taken into account.This paper reports how much active ingredient is deposited on the treated plant surface while preparing various resistance tests in the laboratory (bioassays). The diverse micromorphology of leaf surfaces visualised using cryo-scanning electron microscopy provides an opportunity to verify this. Using the example of the insecticide application in rose cultures as model plants, it is shown that the residue analysis of active ingredient residues in horticultural practice is also an essential component for assessing the susceptibility of pests. In addition, residue analyses of the active substances enable the validation of the bioassays and the comparability of the effects of applications in the laboratory with those in practice.A second study will be published elsewhere, which deals with the sensitivity of selected horticultural pests to various types of plant protection substances
Plant health highlights at international and national level from the introduction of the EU internal market to the present day
Full text linkDer internationale Pflanzenhandel und der Tourismus sowie die Auswirkungen des Klimawandels erhöhen das Risiko der Einschleppung gebietsfremder Pflanzenschadorganismen, die nachfolgend hohe Schäden verursachen können. Schon Ende des 19. Jahrhunderts erkannten viele Staaten, dass den Risiken des Pflanzenhandels zweckmäßigerweise durch eine internationale Kooperation begegnet werden muss. Als wirksam erwiesen sich insbesondere gesetzliche Regelungen wie Einfuhrverbote, spezifische Einfuhranforderungen sowie behördliche Überwachung der Erzeugung, der Einfuhr und des Verbringens von Pflanzen und Pflanzenerzeugnissen. Das Internationale Pflanzenschutzübereinkommen (IPPC) definiert den rechtlich-fachlichen Rahmen für pflanzengesundheitliche Regelungen und ist damit auch Grundlage der Rechtsetzung der Europäischen Union und seiner Mitgliedstaaten. Die EU-Vorschriften zur Verhinderung der Ein- und Verschleppung von Quarantäneschadorganismen wurden durch die Einführung des Binnenmarktes in 1993 und durch Weiterentwicklungen in den Jahren 2016 bis 2019 umfassend harmonisiert und durch vielfältige zusätzliche Elemente effizienter gestaltet. Impulse zur Verbesserung der Rechtsgrundlagen gingen insbesondere vom starken Wachstum des internationalen Pflanzenhandels und Reiseverkehrs, der Entwicklung des IPPC sowie der Evaluierung der Wirksamkeit der pflanzengesundheitlichen Regelungen nach Etablierung des Binnenmarktes aus. Dieser Beitrag beleuchtet sowohl bedeutsame Einschleppungen von Quarantäneschadorganismen als auch wichtige Fortschritte auf dem Weg zur Etablierung der derzeit gültigen Gegenmaßnahmen. Insbesondere für die letzten 30 Jahre werden die Anpassungen der Regelungen und Standards sowie die Zusammenarbeit der in der Pflanzengesundheit tätigen Organisationen auf nationaler, EU und internationaler Ebene erläutert.The globalization of plant trade and tourism as well as the effects of climate change are increasing the risk of the introduction of non-native plant pests, which can subsequently cause considerable damage. As early as the end of the 19th century, many countries recognized that the risks of plant trade should be countered by international cooperation. Legal regulations such as import bans, specific import requirements and official monitoring of the production, import and movement of plants and plant products proved to be particularly effective. The International Plant Protection Convention (IPPC) defines the legal and technical framework for phytosanitary regulations and is therefore the basis for the legislation of the European Union and its Member States. The EU regulations to prevent the introduction and spread of quarantine pests were comprehensively harmonized through the introduction of the internal market in 1993 and through further developments in the years 2016 to 2019 and made more efficient through a variety of additional elements. The strong growth of international plant trade and travel, the development of the IPPC and the evaluation of the effectiveness of phytosanitary regulations following the establishment of the internal market have provided impetus for improving legislation. This article highlights both significant introductions of quarantine pests and important progress towards establishing the current countermeasures. In particular, the adaptations of regulations and standards as well as the cooperation of organizations active in plant health at national, EU and international level are explained for the last 30 years
Surveys: Curse or blessing for plant health – an interim assessment
Full text linkSeit dem 14.12.2019 sind die Mitgliedstaaten der EU verpflichtet, Erhebungen zu allen geregelten Unionsquarantäneschädlingen im Rahmen von Mehrjahresprogrammen durchzuführen. Damit hat sich die Anzahl der Erhebungen drastisch erhöht. In Deutschland wurden die Pflanzenschutzdienste als zuständige Behörden der Bundesländer, aber auch das Julius Kühn-Institut damit vor erhebliche Herausforderungen gestellt. Neben kritischen Aspekten der neuen Vorgaben im Erhebungsbereich, hat es sich aber auch gezeigt, dass in jedem Jahr Nachweise von Unionsquarantäneschädlingen basierend auf den Erhebungen erfolgen. Hinsichtlich einer erfolgreichen Tilgung eines Ausbruchs ist insbesondere die frühzeitige Feststellung eines Auftretens relevant. Hier können amtliche Erhebungen einen wichtigen Beitrag im Rahmen des Frühwarnsystems der EU und damit auch zu einer Verhinderung der Etablierung und weiteren Verbreitung von Unionsquarantäneschädlingen in Deutschland leisten.Since 14.12.2019, the EU member states have been obliged to carry out surveys on all regulated Union quarantine pests as part of multi-annual programs. This has drastically increased the number of surveys. In Germany, the plant protection services as the competent authorities of the federal states, but also the Julius Kühn Institute, have thus been faced with considerable challenges. In addition to critical aspects of the new survey requirements, it has also been shown that Union quarantine pests are detected every year based on the additional surveys. With regard to the successful eradication of an outbreak, the early detection of an outbreak is particularly relevant. Here, official surveys can make an important contribution to the EU\u27s early warning system and thus also to preventing the establishment and further spread of Union quarantine pests
Proposition of critical levels and nutrient sufficiency ranges in leaves of \u27White Moscato\u27 (Vitis vinifera \u27Muscat\u27) and \u27Bordeaux\u27 (Vitis labrusca \u27Ives\u27)
Full text linkThe Compositional Nutrients Diagnosis (CND) can establish indexes that establish deficiency, normality or excess, and even critical levels (CL) or sufficiency ranges (SR) in grapevine leaves. However, this information is scarce in \u27White Moscato\u27 and \u27Bordeaux\u27 cultivars cultivated in subtropical regions of the world. The study aimed to propose the CND, CL and SR indexes of nutrients in leaves of \u27Bordeaux\u27 and \u27White Moscato\u27 grapevine cultivars, cultivated in subtropical conditions. Leaves were collected from 105 \u27White Moscato\u27 and \u27Bordeaux\u27 vineyards. Leaves were prepared, dried, ground and subjected to chemical nutrient analysis. Productivity was evaluated. The nutritional status of the grapevine was calculated using the CND method. The CND-r2 indexes were effective in establishing the nutritional status of \u27White Moscato\u27 and \u27Bordeaux\u27 grapevines, in relation to the concentration of nutrients in leaves of N, P, K, Ca, Mg, B, Cu, Fe, Mn and Zn in deficient, adequate and excessive concentrations. The application of the CND method in the grapevine database showed lower SRs for macronutrients N, K, Ca, Mg and S, and the breadth of the nutritional range for nutrients N, K, Mg, and Fe was smaller than reported in literature. The CND methodology established the critical level and nutrient sufficiency ranges suitable under current grapevine production conditions. Multi-nutrient combinations were more effective than the analysis of a single nutrient in expressing that the limitation of a certain element can reduce the productivity of the grapevines
Application of arbuscular mycorrhizal fungi and potassium nitrate improves physiological performance and glycyrrhizin production of licorice under salt stress
Full text linkTo examine the effects of potassium nitrate fertilizer (40 and 80 kg ha-1) and inoculation with arbuscular mycorrhizal fungi (25, 50, and 100 g inoculum) on the physiological performance and glycyrrhizin production of licorice plants (Glycyrrhiza glabra L.) under salt stress (irrigation with 4 and 8 dSm-1 of saline water), two field experiments were conducted in 2021 and 2022. Salinity reduced the physiological performance of plants but increased the concentration of glycyrrhizin in the roots. The application of potassium nitrate, especially at a rate of 40 kg ha-1, along with mycorrhiza, resulted in increased nutrient content, antioxidative activities (catalase, peroxidase, and superoxide dismutase activities), membrane stability index, leaf relative water content, photosynthetic pigment content, glycyrrhizin production, and growth (about 45%) of licorice plants. On the other hand, the treatment with KNO3 and mycorrhiza reduced the accumulation of sodium in plant tissues (about 16%). The application of 40 kg ha-1 KNO3 with 50 g of inoculum was found to be the superior treatment for improving the performance of licorice plants under salt stress. According to the findings of this study, the use of KNO3 in combination with arbuscular mycorrhizal fungi is a successful approach to improve plant growth and productivity under saline conditions
Viscospora peruviscosa, a new fungus in the Glomeraceae from a plantation of Theobroma cacao in Peru
Full text linkA new fungus, Viscospora peruviscosa, was detected in a Theobroma cacao plantation in the Huallaga province of San Martín State in Peru.The fungus was propagated in the greenhouse on Sorghum vulgare and Brachiaria brizantha. The fungus is similar to V. viscosa as it has two spore wall layers and also a viscose outer spore surface, but its spores are smaller ((30-) 44-56 (-65) × (25-) 44-54 μm) and the subtending hyphae generally are more pronounced funnel-shaped. Also, the walls of the spores and subtending hyphae are thinner than in V. viscosa. Phylogenetically, both species form two well separated sister clades in the genus Viscospora. Based on the partial nrDNA gene, the two species have 90-91% maximum identity (MI). So far, the fungus is only known from the cacao plantation in Huallaga. No environmental sequences in the public data bases suggest that the fungus has already been found elsewhere in the neotropics or worldwide. This is the second species in the genus Viscospora (Glomeraceae) described, hence Viscospora is no longer monospecific
Contributions of the VitisGen2 project to grapevine breeding and genetics
Full text linkThe VitisGen projects (2011-2022) have improved the tools available for breeding new grapevine cultivars with regional adaptation, high quality, and disease resistance. VitisGen2 (the second project in the series) was a multi-state collaboration (USDA-Geneva, New York; University of California, Davis; USDA-Parlier, California; Cornell University; Missouri State University; University of Minnesota; South Dakota State University; Washington State University; North Dakota State University; and E&J Gallo, California) to develop improved genetic mapping technology; to identify useful DNA marker-trait associations; and to incorporate marker-assisted selection (MAS) into breeding programs. A novel genetic mapping platform (rhAmpSeq) now provides 2000 + markers that are transferable across the Vitis genus. rhAmpSeq has been used in California, New York, Missouri, and South Dakota to identify new QTL for powdery and downy mildew resistance. In addition, fruit/flower traits that would normally take years to phenotype have been associated with predictive markers accessible from seedling DNA (e.g. malate metabolism, anthocyanin acylation, bloom phenology and flower sex). Since 2011, the project has used MAS to screen thousands of grape seedlings from public breeding programs in the United States and has produced “Ren- Stack” public domain lines to enable simultaneous access to 4 or 6 powdery mildew resistance loci from single source genotypes. High-throughput phenotyping for powdery and downy mildew resistance has been revolutionized with the Blackbird automated-imaging system powered by artificial intelligence for image analysis. Affordable DNA sequencing along with phenotyping innovations are transforming grapevine breeding
Topography interactions with the Atlantic Ocean and its impact on Vitis vinifera L. \u27Tannat\u27
Full text linkClimate is one of the main factors conditioning the chemical composition of grapes and wine. At a vineyard scale, during the growing season, topography can explain spatial temperature variability. Furthermore, each topographical factor (altitude, slope, exposure) may have a different impact on grapevine production, even in low altitude terrains. This work aims to evaluate the mesoclimate of Uruguay\u27s Atlantic region and determine the topography and ocean\u27s effect on temperature and, thus on the response of the \u27Tannat\u27 grapevine. Data from 19 temperature sensors, installed in a coastal vineyard under contrasted topography conditions, were used over three growing seasons in order to study the relationships between bioclimatic indicators of different sites and the plant response of nine \u27Tannat\u27 plots under similar agronomical management and soil type. Mesoclimate, especially due to altitude and exposition to the ocean winds, mostly explained \u27Tannat\u27 variability. Significant differences in extreme temperatures (minimum and maximum) were observed: The plots at higher altitudes (118-140 m a.s.l.) exposed to oceanic winds had a lower daytime temperature than the plot sheltered at lower altitude (70-94 m a.s.l.). The average difference was 0.9 °C during the hottest summer, reaching 1,7 °C between the most contrasted sites. In particular, the local sea breeze circulation during heat waves of the ripening period, prevent extreme high temperatures in sites facing the ocean. Temperature drop of 4.3°C in upwind sites was noticed, against 0.9°C in sheltered plots. The plots at lower altitude presented a nighttime temperature lower than plots at higher altitude (up to 1.0°C lower, on average, during ripening), thus resulting in greater diurnal thermal amplitude (1.5 °C greater). A direct association between altitude, mesoscale temperature and \u27Tannat\u27 grape metabolites was observed for three consecutive years: plots at higher altitude recorded significative greater malic acid (+1.7 g L-1), while plots at lower altitude recorded greater anthocyanin potential (ApH1) (+1920 mg L-1). Other variables such as soluble solids, total titratable acidity, pH and polyphenols were differentiated at least over one growing season. No significant differences in agronomic response parameters such as yield, pruning weight and Ravaz Index were observed. Topographic differences less than 70 m a.s.l. but enhanced by the Atlantic Ocean influence, made it possible to differentiate plots with equal vine responses. Seasonal and spatial climatic characterization of the region at fine scale along with grapevine response will allow to optimize agronomic decisions especially in search of fresh terroirs where the vines can adapt to climate change
