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Residual soils, residues from potato and beet processing, are one of the most important pathways for the spread of quarantine pests in potato and beet cultivation. In terms of plant quarantine, residual soils must be free from quarantine pests in order to be able to return them to agricultural habitats. Cyst nematodes, which are highly persistent to environmental influences, are particularly challenging. In the GlobRISK project, the anaerobic soil disinfestation (ASD) developed in the Netherlands was transferred and optimized as an alternative to the complete flooding of entire fields (inundation). ASD was tested for the specific application of disinfesting residual soils from regulated potato cyst nematodes (Globodera pallida and G. rostochiensis) and non-regulated beet cyst nematodes (Hetereodera schachtii). In this study, the effect of ASD on cyst nematodes was investigated at three levels: in microplots under natural environmental conditions, in mesocosms of 15 L buckets in the climate chamber and in microcosms in the laboratory. In the microplot experiment, higher temperatures were achieved by incorporating and foil covering with the product Herbie®72 (Thatchtec/Soilwise), which was specially developed for ASD, compared to uncovered plots including controls without Herbie®72. However, the development of anaerobic conditions in the treated plots was incomplete due to shallow incorporation of the substrate, insufficient soil moisture and incomplete foil cover. As a result, the reduction in hatching rate of G. pallida was only slightly reduced at 98% hatch reduction could only be achieved for soils from three different locations in mesocosms with a volume of 15 L of soil when the substrate Herbie®72 was incorporated, under conditions of complete air exclusion combined with compaction and water saturation of the soils treated. This could be also shown for the substrate mustard seed meal from Brassica juncea, which was incorporated as an alternative to Herbie®72. In summary, it can be concluded that ASD (anaerobic soil disinfestation) and biofumigation using mustard seed meal instead of Herbie®72 under controlled conditions represent an effective alternative to inundation.

The Oriental tea tortrix Homona magnanima Diakonoff, 1948 (Lepidoptera: Tortricidae) has been intercepted three times in Germany on imported plants from Japan since 2023. The moth was found on bonsai of Taxus sp., T. cuspidata and Pinus thunbergii. The findings were diagnosed in a close cooperation between official laboratories in the federal states of Baden-Wurttemberg (Landwirtschaftliches Technologiezentrum Augustenberg), Brandenburg (Landesamt für Ländliche Entwicklung, Landwirtschaft und Flurneuordnung), North Rhine-Westphalia (Landwirtschaftskammer) and the National Reference Laboratory located at Julius Kühn Institute (NRLJKI). DNA barcoding of the COI gene region revealed identical sequences for all findings in Germany. However, the final confirmation by a database comparison with NCBI GenBank and the BOLD database was insufficient, presumably due to incorrectly referenced but also missing entries. Phylogenetic analysis in combination with information on native distribution, host tree preferences and morphological features allowed for a species assignment as Homona magnanima. Following the identification, an Express-Pest Risk Analysis was conducted by the JKI, resulting in a categorisation of the tortrix as a potential quarantine pest.

Diese Übersichtsarbeit verfolgt das Ziel, über bakterielle kontraktile Phagenderivate (englisch CPTPs) und ihr Potenzial als effiziente und Schadorganismus-spezifische Alternativen zu konventionellen chemischen Pflanzenschutzmitteln in der Land-/Forstwirtschaft und im Gartenbau zu informieren. CPTPs werden von verschiedenen Bakterien in diversen Habitaten für den interbakteriellen Konkurrenzkampf sowie zur Beeinflussung eukaryotischer Wirte, wie Pilze und Insekten, verwendet. Diese Arbeit präsentiert interessante und bemerkenswerte Beispiele für den vielfältigen Einsatz von CPTPs als leistungsfähige biologische Bekämpfungsmittel. Wir stellen die verschiedenen Typen von CPTPs vor und legen einen besonderen Fokus auf diejenigen, die eine Wirkung gegen Schadinsekten besitzen. Zusätzlich stellen wir zwei kürzlich etablierte Webservices vor, die das permanent wachsende Wissen über CPTPs mit einem Auswahlverfahren für die besten Bakterienkandidaten kombinieren, um eine zielgerichtete Anwendung der CPTPs in der nachhaltigen Pflanzenproduk­tion zu ermöglichen.

Spinal diffusion tensor imaging (sDTI) is still a challenging technique for selectively evaluating anatomical areas like the pyramidal tracts (PT), dorsal columns (DC), and anterior horns (AH) in clinical routine and for reliably quantifying white matter anisotropy and diffusivity. In neurodegenerative diseases, the value of sDTI is promising but not yet well understood.The objective of this prospective, single-center study was to evaluate the long fiber tract degeneration within the spinal cord in normal aging (n = 125) and to prove its applicability in pathologic conditions as in patients with molecular genetically confirmed hereditary spastic paraplegias (HSP; n = 40), a prototypical disease of the first motor neuron and in some genetic variants with affection of the dorsal columns. An optimized monopolar Stejskal-Tanner sequence for high-resolution, axial sDTI of the cervical spinal cord at 3.0 T with advanced standardized evaluation methods was developed for a robust DTI value estimation of PT, DC, and AH in both groups.After sDTI measurement at C2, an automatic motion correction and an advanced semi-automatic ROI-based, standardized evaluation of white matter anisotropy and diffusivity was performed to obtain regional diffusivity measures for PT, DC, and AH. Reliable and stable sDTI values were acquired in a healthy population without significant decline between age 20 and 65. Reference values for PT, DC, and AH for fractional anisotropy (FA), mean diffusivity (MD), and radial diffusivity (RD) were established.In HSP patients, the decline of the long spinal fiber tracts could be demonstrated by diffusivity abnormalities in the pyramidal tracts with significantly reduced PTFA (p

The dissemination of soil tares in the potato and sugar beet processing industry is one of the main paths for the spread of potato cyst nematodes (PCN), a severe quarantine pest. Efficient measures for the disinfestation of tare soil from PCN, but also from beet cyst nematodes (BCN), are needed. In our study, Globodera pallida (a PCN) and Heterodera schachtii (a BCN) cysts were sealed in gauze bags and imbedded in sedimentation basins. The cysts were either placed (a) in a presedimentation basin (Brukner basin) for three days, (b) in the presedimentation basin for three days and subsequently in sedimentation basins for nine weeks or (c) in sedimentation basins for nine weeks (without presedimentation). We tested the viability of the eggs and juveniles by hatching assays and using the reproduction rates in bioassays. We demonstrated that PCN and BCN imbedded in a sedimentation basin were only still showing some hatching activity after 2.5 weeks, while no hatching was observed when an additional Brukner basin treatment was conducted before sedimentation.

Das Nachrichtenblatt für den Deutschen Pflanzenschutzdienst, unser heutiges Journal für Kulturpflanzen, feiert seinen 100. Geburtstag. Seinem Ziel, „den im praktischen Pflanzenschutzdienst Tätigen Belehrung und Informationen (zu) übermitteln“, wie Otto Appel zur Einführung schrieb, ist es bis heute treu geblieben. Dies gilt auch für den Bereich der Nematologie. Die Themen haben sich dabei über die Zeit weiterentwickelt. Standen früher Biologie und Wirtspflanzenspektrum einzelner Arten pflanzenparasitärer Nematoden im Fokus des Interesses, so sind es heute Wirt-Parasit Interaktionen, Resistenz und Toleranz von Kulturpflanzen oder der Einfluss von Klimawandel und Globalisierung auf die Verbreitung und das Schadpotenzial der Nematoden. Der vorliegende Beitrag blickt zurück auf die Themen vor 100 Jahren, stellt am Beispiel laufender Arbeiten am Julius Kühn-Institut aktuelle Forschungsthemen vor und gibt einen Ausblick auf die Themen der Zukunft.

Eine nicht-invasive Diagnose holzzerstörender Schadorganismen ist von großer Bedeutung um Eingriffe in kostbare Holzprodukte und lebende Bäume auf ein Minimum zu beschränken. Hier stellen wir zwei ganz unterschied­liche Methoden vor, eine physikalische und eine molekularbiologische, die einen schonenden Nachweis von Insekten­larven im Holz ermöglichen. Beide Methoden sind bereits zum Teil erfolgreich zur Analyse des Asiatischen Laubholzbockkäfers (Anoplophora glabripennis, ALB) eingesetzt worden und eignen sich als Frühwarnsysteme in der Bekämpfung von Quarantäneschadinsekten.

Dem JKI wurde im April 2019 durch das Bundesministerium für Ernährung und Landwirtschaft (BMEL) die Funktion des nationalen Referenzlaboratoriums (NRL) für Schadorganismen der Pflanzen zugewiesen. Mit dieser Funktion des NRL für Deutschland sind bestimmte Zuständigkeiten und Aufgaben verbunden, die in der EU-Verordnung 2017/625 (EU, 2017) geregelt sind. Dazu gehören auch Referenzuntersuchungen bzw. die Diag­nose von Quarantäneschadorganismen (QSO). Das NRL stellt eine übergeordnete Einheit innerhalb des JKI dar. Durch insgesamt 14 Prüflabore der JKI-Institute für Pflanzenschutz in Ackerbau und Grünland (A), nationale und internationale Angelegenheiten der Pflanzengesundheit (AG), Epidemiologie und Pathogendiagnostik (EP), Pflanzenschutz in Gartenbau und Forst (GF), Pflanzenschutz in Obst- und Weinbau (OW) wird die Referenzfunktion bei der Diagnose zu verschiedensten (Quarantäne)-Schadorganismen der Pathogengruppen Bakterien, Insekten, Nematoden, Pilze (einschließlich Oomyceten), Phytoplasmen und Viren wahrgenommen.

Zwei Organismengruppen gehören zu den besonders wider­standsfähigen und ertragsmindernden Schadorganismen an der Kartoffel: (1) Zystennematoden der Gattung Globodera, wie der Weiße (G. pallida) und der Goldene Kartoffelzystennematode (G. rostochiensis), sowie (2) Synchytrium endobioticum, der Erreger des Kartoffelkrebses. Ihr Status als geregelte, schwer kontrollierbare Unions-Quarantäneschadorganismen ist ihren äußerst robusten Dauerstadien (Zysten bzw. Wintersporangien) zuzuschreiben sowie dem Auftreten einzelner Populationen mit hoher Virulenz. Ihre Verbreitung ist daher unbedingt zu vermeiden. Ein hohes Risiko einer Verschleppung bergen die jährlich mehreren hunderttausend Tonnen bei der Kartoffelverarbeitung anfallenden Resterden mit nicht zuzuordnender Herkunft. Um eine unbedenk­liche Rückführung der Erden auf Ackerflächen zu ermöglichen, wird im Projekt GlobRISK die Optimierung bzw. Ergänzung phytosanitärer Verfahren zur Dekontamina­tion der Resterden von Kartoffelzystennematoden vorangetrieben. Im Drittmittelprojekt INNOKA beabsichtigen wir, innovative Nachweisverfahren für S. endobioticum aus Resterden zu entwickeln und somit Grundlagen für weitere Forschungsarbeiten zur Dekontamination S. endo­bioticum belasteter Resterden zu schaffen.

As a severe danger to potato plants, potato cyst nematodes (PCNs) are regulated quarantine pests in many countries. Adhering soils to potato or other tuber crops provoke the uncontrolled spread of the pest after their industrial processing. The disinfection of soil tares to inactivate PCNs is therefore compulsory. In the present study, we test whether the viability and formation of PCN cysts are suppressed after treatment with γ and β irradiation. In a first experiment, nematode cysts were treated with γ or β irradiation without soil matrix to determine the minimum dose parameters in a range between 0–12 kGy. Subsequently, two representative soils that included cysts were irradiated. Irradiation effects on PCN viability and the formation of new cysts were evaluated via hatching tests and bioassays with susceptible potato plants, respectively. In addition, maize seedling growth was tested in irradiated soil tares. We found that next to γ also, β irradiation suppressed the hatch of PCN juveniles and its formation of cysts when placed in soil tares. The growth of maize seedlings was not impaired in irradiated soils compared to control soils. Both γ and β irradiation treatment offer an organism group selective and effective phytosanitary measures to disinfect soil tares from PCNs.

Selenium (Se) is an important micronutrient but also a strong toxin with a narrow tolerance range for many organisms. As such, a globally heterogeneous Se distribution in soils is responsible for various disease patterns (i.e. Se excess and deficiency) and environmental problems, whereby plants play a key role for the Se entrance into the biosphere. Selenium isotope variations were proved to be a powerful tracer for redox processes and are therefore promising for the exploration of the species dependent Se metabolism in plants and the Se cycling within the Critical Zone. Plant cultivation setups enable systematic controlled investigations, but samples derived from them-plant tissue and phytoagar-are particularly challenging and require specific preparation and purification steps to ensure precise and valid Se isotope analytics performed with HG-MC-ICP-MS. In this study, different methods for the entire process from solid tissue preparation to Se isotope measurements were tested, optimized and validated. A particular microwave digestion procedure for plant tissue and a vacuum filtration method for phytoagar led to full Se recoveries, whereby unfavorable organic residues were reduced to a minimum. Three purification methods predominantly described in the literature were systematically tested with pure Se solution, high concentrated multi-element standard solution as well as plant and phytoagar as target matrices. All these methods efficiently remove critical matrix elements, but differ in Se recovery and organic residues. Validation tests doping Se-free plant material and phytoagar with a reference material of known Se isotope composition revealed the high impact of organic residues on the accuracy of MC-ICP-MS measurements. Only the purification method with no detectable organic residues, hydride generation and trapping, results in valid mass bias correction for plant samples with an average deviation to true δ82/76Se values of 0.2 ‰ and a reproducibility (2 SD) of ± 0.2 ‰. For phytoagar this test yields a higher deviation of 1.1 ‰ from the true value and a 2 SD of ± 0.1 ‰. The application of the developed methods to cultivated plants shows sufficient accuracy and precision and is a promising approach to resolve plant internal Se isotope fractionations, for which respective δ82/76Se values of +2.3 to +3.5 ‰ for selenate and +1.2 to +1.9 ‰ for selenite were obtained.

This study investigated the impact of constitutively expressed Trichoderma atroviride genes encoding exochitinase nag70 or endochitinase ech42 in transgenic lines of the apple cultivar Pinova on the symbiosis with arbuscular mycorrhizal fungi (AMF). We compared the exo- and endochitinase activities of leaves and roots from non-transgenic Pinova and the transgenic lines T386 and T389. Local and systemic effects were examined using own-rooted trees and trees grafted onto rootstock M9. Scab susceptibility was also assessed in own-rooted and grafted trees. AMF root colonization was assessed microscopically in the roots of apple trees cultivated in pots with artificial substrate and inoculated with the AMF Glomus intraradices and Glomus mosseae. Own-rooted transgenic lines had significantly higher chitinase activities in their leaves and roots compared to non-transgenic Pinova. Both of the own-rooted transgenic lines showed significantly fewer symptoms of scab infection as well as significantly lower root colonization by AMF. Biomass production was significantly reduced in both own-rooted transgenic lines. Rootstock M9 influenced chitinase activities in the leaves of grafted scions. When grafted onto M9, the leaf chitinase activities of non-transgenic Pinova (M9/Pinova) and transgenic lines (M9/T386 and M9/T389) were not as different as when grown on their own roots. M9/T386 and M9/T389 were only temporarily less infected by scab than M9/Pinova. M9/T386 and M9/T389 did not differ significantly from M9/Pinova in their root chitinase activities, AMF root colonization and biomass.

Fungi are prominent drivers of ecological processes in soils, so that fungal communities across different soil ecosystems have been well investigated. However, for arable soils taxonomically resolved fine-scale studies including vertical itemization of fungal communities are still missing. Here, we combined a cloning/Sanger sequencing approach of the ITS/LSU region as marker for general fungi and of the partial SSU region for arbuscular mycorrhizal fungi (AMF) to characterize the microbiome in different maize soil habitats. Four compartments were analyzed over two annual cycles 2009 and 2010: a) ploughed soil in 0-10 cm, b) rooted soil in 40-50 cm, c) root-free soil in 60-70 cm soil depth and d) maize roots. Ascomycota was the most dominant phylum across all compartments. Fungal communities including yeasts and AMF differed strongly between compartments. Inter alia, Tetracladium, the overall largest MOTU (molecular operational taxonomic unit), occurred in all compartments, whereas Trichosporon dominated all soil compartments. Sequences belonging to unclassified Helotiales were forming the most abundant MOTUs exclusively present in roots. This study gives new insights on spatial distribution of fungi and helps to link fungal communities to specific ecological properties such as varying resources, which characterize particular niches of the heterogeneous soil environment.

The article provides information on a study which reported significant mass-dependent selenium (Se) isotope variations in modern hot spot-influenced lavas that records ocean-atmosphere oxygenation. Topics discussed include origin of Se isotopic variability in the mantle, recycled sediments from a redox-stratified ocean, and mantle recycling record of atmospheric oxygenation.

Aims: Heart rate variability (HRV) reveals information on the functional state of the autonomic nervous system (ANS). This study was initiated to assess the physiological- and maturational development of the ANS by comparing HRV data of healthy prematures with term infants.Methods: Short-term recordings of HRV in 39 premature healthy infants (29–35 weeks' gestation) were performed and compared with normative data of term infants. Frequency domain HRV parameters are computed in three frequency bands.Results: Gestational age of newborn infants is correlated with HRV. Prematures showed significant lower HRV parameters than term infants. The most significant differences were discerned for HRV parameters reflecting parasympathetic activity, whereas the pulse of the baro-receptor reflex was similar for prematures and term infants at 0.07 Hz (0.1 Hz adults). A respiratory peak in the HF-band according to respiratory sinus arrhythmia (RSA), as is common in adults, was not detected for prematures as it is not detected in term infants.Conclusions: Maturation of the ANS is accompanied by increasing HRV with a pronounced increase of parasympathetic activity. These changes are measurable by short-term recordings. The physiological pulses concerning baroreceptor reflex activity and respiratory modulation were similar in prematures and term infants. [ABSTRACT FROM AUTHOR]

Lead clusters in the size range between about n = 15 and 40 have recently shown to exhibit complex dissociation spectra due to sequential and competing decays. In order to disentangle the pathways the exemplary clusters have been stored and size selected in a Penning trap and irradiated by nanosecond laser pulses. We present time-resolved measurements at time scales from several tens of microseconds to several hundreds of milliseconds. The study results in strong evidence that decays not only by neutral monomer evaporation but also by neutral heptamers breaking off. In addition, the decays are further followed to smaller products. The corresponding decay and growth times show that also dissociates by either monomer evaporation or heptamer break-off. Furthermore, the product may well be a result of heptamer break-off from —as the second step of a sequential heptamer decay. [ABSTRACT FROM AUTHOR]

The Solomon island arc, SW Pacific, is of particular interest for understanding subduction zone volcanism, as magmatism in the active part of the arc is dominated by mafic melts, thus permitting direct insights into mantle processes. Along the Solomon island arc, the Indian–Australian plate is subducting at present beneath the Pacific plate. However, until at least c. 12 Myr ago, the Pacific plate was subducting beneath the Indian–Australian plate until the Cretaceous Ontong Java Plateau collided with the northern Solomon island arc. To evaluate the effects of the changes in tectonic regime on lava compositions, we present a comprehensive Sr–Nd–Hf–Pb isotope, major element and trace element dataset, covering lavas erupted along the entire island arc (c. 1000 km). Basalts and andesites represent the most abundant rock types. Picrites and ankaramites occur in the New Georgia Group of the Solomon Islands, where they erupted above the subducting Woodlark spreading center, and also in the Santa Cruz archipelago, north of Vanuatu, where the Rennell Fracture Zone is subducting. Recent work has also identified the presence of adakites (Sr/Y up to c. 200), and high-Mg andesites (MgO > 5 wt %, Sr/Y c. 11–46). Most of the high-Mg andesites are genetically linked to the adakites, but some of the high-Mg andesites show affinities to boninitic compositions. Large ion lithophile element abundances in most Solomon island arc magmas indicate a strong source overprint by subduction components. 87Sr/86Sr and ∊Nd values along the arc range from 0·7029 to 0·7052 and from +5·8 to +8·3, respectively. The Sr–Nd values partially overlap the compositions of oceanic basalts from the Indian–Australian plate. Measured ∊Hf values range from +10·5 to +14·6. If corrected for contributions from subduction components, combined ∊Hf–∊Nd systematics also indicate that most of the studied Solomon arc lavas were generated within the Indian-type mantle domain. However, a few samples display ∊Hf–∊Nd compositions resembling those of the Pacific-type mantle domain. These samples either originate from older Pacific basement (basalts) or represent melts derived from subducted Pacific crust (adakites). Lead isotope compositions, controlled by subduction components, can be used to identify the presence of two distinct types of subduction components that originate (1) from the Pacific plate including Ontong Java Plateau material (> 6 Myr old) and (2) from the more recently subducted Indian–Australian plate. Combined Hf–Nd–Pb isotope data also reveal that lower parts of the Ontong Java Plateau entered the mantle wedge, as previously postulated by geophysical models. [ABSTRACT FROM AUTHOR]