Untersuchungen über die Wechselwirkung zwischen Stallmist- und Stickstoffdüngung

Auf der Grundlage von 3‐jährigen Feldversuchen mit den Winterformen von Gerste, Roggen, Triticale und Weizen werden im Nordosten Deutschlands in unmittelbarer Nähe der Ostsee Untersuchungen zum Einfluß einer gesteigerten Intensität auf den Ertrag durchgeführt.

Die Versuchsanlage beinhaltet 4 Intensitätsstufen je Getreideart. Die Intensitätsstufen unterscheiden sich durch steigende Aufwendungen bei Stickstoff, Herbiziden, Fungiziden, Wachstumsreglern und Spurenelementen.

Insgesamt wird festgestellt, daß die Steigerung der Intensität zu einer Erhöhung des Ertrages führt. Allgemein wird in der höchsten Intensitätsstufe auch der höchste Ertrag erzielt.

Die Arten reagieren unterschiedlich auf die Intensitätsänderung. Auch zwischen den Sorten, geprüft am Weizen, bestehen in der Reaktion auf die Intensitätssteigerung Unterschiede. Prinzipiell ist durch eine genaue Kenntnis der Sortenreaktion eine höhere Ausschöpfung des genetisch fixierten Ertragspotentials möglich. In Anbetracht der umfangreichen Sortimente dürfte eine sortenspezifische Anbautechnik für praktische Zwecke kaum realisierbar sein.     

Spectral fingerprinting: sediment source discrimination and contribution modelling of artificial mixtures based on VNIR-SWIR spectral properties

Purpose

Knowledge of the origin of suspended sediment is important for improving our understanding of sediment dynamics and thereupon support of sustainable watershed management. An direct approach to trace the origin of sediments is the fingerprinting technique. It is based on the assumption that potential sediment sources can be discriminated and that the contribution of these sources to the sediment can be determined on the basis of distinctive characteristics (fingerprints). Recent studies indicate that visible–near-infrared (VNIR) and shortwave-infrared (SWIR) reflectance characteristics of soil may be a rapid, inexpensive alternative to traditional fingerprint properties (e.g. geochemistry or mineral magnetism).

Materials and methods

To further explore the applicability of VNIR-SWIR spectral data for sediment tracing purposes, source samples were collected in the Isábena watershed, a 445 km² dryland catchment in the central Spanish Pyrenees. Grab samples of the upper soil layer were collected from the main potential sediment source types along with in situ reflectance spectra. Samples were dried and sieved, and artificial mixtures of known proportions were produced for algorithm validation. Then, spectral readings of potential source and artificial mixture samples were taken in the laboratory. Colour coefficients and physically based parameters were calculated from in situ and laboratory-measured spectra. All parameters passing a number of prerequisite tests were subsequently applied in discriminant function analysis for source discrimination and mixing model analyses for source contribution assessment.

Results and discussion

The three source types (i.e. badlands, forest/grassland and an aggregation of other sources, including agricultural land, shrubland, unpaved roads and open slopes) could be reliably identified based on spectral parameters. Laboratory-measured spectral fingerprints permitted the quantification of source contribution to artificial mixtures, and introduction of source heterogeneity into the mixing model decreased accuracies for some source types. Aggregation of source types that could not be discriminated did not improve mixing model results. Despite providing similar discrimination accuracies as laboratory source parameters, in situ derived source information was found to be insufficient for contribution modelling.

Conclusions

The laboratory mixture experiment provides valuable insights into the capabilities and limitations of spectral fingerprint properties. From this study, we conclude that combinations of spectral properties can be used for mixing model analyses of a restricted number of source groups, whereas more straightforward in situ measured source parameters do not seem suitable. However, modelling results based on laboratory parameters also need to be interpreted with care and should not rely on the estimates of mean values only but should consider uncertainty intervals as well.     

Grassland and globalization – challenges for north‐west European grass and forage research

The concept of sustainable intensification has recently been developed to raise productivity (as distinct from increasing volume of production) while reducing environmental impacts. This means increasing yields per unit of inputs (including nutrients, water, energy capital and land) as well as per unit of undesirable outputs (such as greenhouse gas emissions, water pollution or loss of biodiversity). It is thus helpful to understand ‘intensification’ as referring to ‘environmental factor productivity’ or ‘eco‐efficiency’. Worldwide, grassland is the most important agroecosystem delivering ecosystem services ranging from feed supply for ruminants and soil carbon storage to habitats of biodiversity. However, worldwide, grassland is under threat due to intensified land use and land‐use changes from grass to arable. In this article, we (i) highlight ecosystem services of selected grassland biomes abroad of Europe, (ii) show evidence of sustainable as well as non‐sustainable intensification options in these grassland biomes linked to European agriculture by exports of agricultural commodities (e.g. soy) and (iii) derive research strategies for north‐west European grassland research and management to match sustainable intensification strategies for the grassland‐based dairy industry.     

Change in fracturing and colouring of solid spruce and ash wood after thermal modification

Effects of different thermal treatments (maximum treatment temperatures of 200, 210 and 220°C for 2.5 hours) on solid spruce (Picea abies L. Karst.) and ash (Fraxinus excelsior L.) were investigated in this study. The fracture behaviour in radial/longitudinal as well as in tangential/longitudinal and the change of the wood colour (CIEL*a*b* colour space) on all principal anatomical surfaces (cross sectional, radial and tangential) were analysed. The specific fracture energy and the maximum breaking load decreased almost significantly after all thermally treated samples in comparison to the untreated (standard dried) sample. The wood colour changed also significantly, in particular the lightness decreased with increasing intensity of thermal treatment on all investigated surfaces. A comparison of the percentage loss of the different fracture and colour values has shown a strong correlation between the maximum breaking load and the lightness after several thermal treatments, in both investigated crack propagation systems, on all measured surfaces and for both analysed species.     

饲料加工厂面临饲用玉米干酒糟及其可溶物带来的挑战

根据最近的研究成果,家禽日粮中添加高达20％的玉米干酒糟及其可溶物（Distillers Dried Grains with Soluble,DDGS）是切实可行的。然而,为能取得最佳添加效果,必须对影响其质量的各种因素进行仔细监测。     

Biology of influenza viruses

An attempt is made to present out of a multitude of available data those that will allow an insight into the biology of the influenza viruses, in order to contribute to the understanding of the present situation of influenza virus infections and the risk of pandemic influenza.This short overview is based on several reviews presented by others, some own reviews and statements, as well as some recent publications in scientific journals.     

Small strongyle infection: consequences of larvicidal treatment of horses with fenbendazole and moxidectin

The study was undertaken to evaluate adverse effects of larvicidal treatment in horses naturally infected with cyathostomins. Out of 24 ponies kept on pasture, four animals were housed in September and anthelmintically cured to serve as worm-free controls (group C-0). The others were housed in December. Eight animals each were treated 8 weeks later with 5 x 7.5mg/kg fenbendazole (FBZ) or 1 x 0.4 mg/kg moxidectin (MOX). Four animals remained untreated (group C-i). Two, 4, 6 and 14 days after the end of treatment two animals of each of the treated groups were necropsied together with group C-0 and C-i animals. Infected animals before treatment showed weight loss, eosinophilia, increased plasma protein and globulin contents. Treatment was followed by weight gain and temporal plasma protein and globulin increase. Proportions of CD4+ and CD8+ T lymphocytes in the peripheral blood did not differ between the groups before treatment but dropped significantly temporally after FBZ treatment. Group C-0 was worm-free at necropsy. Group C-i animals contained variable numbers of luminal and tissue cyathostomins. Histological sections showed larval stages in the lamina propria und submucosa surrounded by macrophages. Either treatment was effective against luminal parasites and reduced the number of larvae in the bowel wall beginning 4-6 days after FBZ and 6-14 days after MOX treatment. Histologically, as a first reaction after FBZ application T lymphocytes accumulated around morphologically intact L4 in the submucosa. Subsequently T lymphocytes associated with eosinophils infiltrated the submucosa. Parasites became enclosed by granulomas with eosinophils adhering to and invading the larvae which started to disintegrate on day 4. Later on, particularly on day 14 inflammation extended into the mucosa and was frequently associated with ulcerations. Third stage larvae in general and L4 in the lamina propria, however, seemed not to be affected until day 14 and even then, parasites did usually not generate extensive inflammation. After MOX treatment severe morphologically detectable alterations of tissue larvae could not be observed earlier than day 14. Different from FBZ treatment, larvae disintegrated and were obviously resorbed without causing severe inflammation in the gut wall. In conclusion treatment with either drug was efficacious against tissue larvae of cyathostomins but there may be different clinical consequences: in contrast to MOX effects, killing of larvae due to FBZ was associated with severe tissue damage, which clinically may correspond to reactions caused by synchronous mass emergence of fourth stage larvae, i.e., may mimic larval cyathostominosis.     

Validated method for quantification of genetically modified organisms in samples of maize flour

Sensitive and accurate testing for trace amounts of biotechnology-derived DNA from plant material is the prerequisite for detection of 1% or 0.5% genetically modified ingredients in food products or raw materials thereof. Compared to ELISA detection of expressed proteins, real-time PCR (RT-PCR) amplification has easier sample preparation and detection limits are lower. Of the different methods of DNA preparation CTAB method with high flexibility in starting material and generation of sufficient DNA with relevant quality was chosen. Previous RT-PCR data generated with the SYBR green detection method showed that the method is highly sensitive to sample matrices and genomic DNA content influencing the interpretation of results. Therefore, this paper describes a real-time DNA quantification based on the TaqMan probe method, indicating high accuracy and sensitivity with detection limits of lower than 18 copies per sample applicable and comparable to highly purified plasmid standards as well as complex matrices of genomic DNA samples. The results were evaluated with ValiData for homology of variance, linearity, accuracy of the standard curve, and standard deviation.     

Genetic diversity of Fusarium oxysporum and related species pathogenic on tomato in Algeria and other Mediterranean countries

In order to characterize the pathogen(s) responsible for the outbreak of fusarium diseases in Algeria, 48 Fusarium spp. isolates were collected from diseased tomato in Algeria and compared with 58 isolates of Fusarium oxysporum originating from seven other Mediterranean countries and 24 reference strains. Partial sequences of the translation elongation factor EF‐1α gene enabled identification of 27 isolates as F. oxysporum, 18 as F. commune and three as F. redolens among the Algerian isolates. Pathogenicity tests confirmed that all isolates were pathogenic on tomato, with disease incidence greater at 28°C than at 24°C. All isolates were characterized using intergenic spacer (IGS) DNA typing, vegetative compatibility group (VCG) and PCR detection of the SIX1 (secreted in xylem 1) gene specific to F. oxysporum f. sp. lycopersici (FOL). No DNA polymorphisms were detected in the isolates of F. redolens or F. commune. In contrast, the 27 Algerian isolates of F. oxysporum were shown to comprise nine IGS types and 13 VCGs, including several potentially new VCGs. As none of the isolates was scored as SIX1+, the 27 isolates could be assigned to F. oxysporum f. sp. radicis‐lycopersici (FORL). Isolates from Tunisia were also highly diverse but genetically distinct from the Algerian isolates. Several Tunisian isolates were identified as FOL by a PCR that detected the presence of SIX1. The results show that isolates from European countries were less diverse than those from Tunisia. Given the difference between Algerian populations and populations in other Mediterranean countries, newly emergent pathogenic forms could have evolved from local non‐pathogenic populations in Algeria.