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Trial Report – Closed Transfer Systems (CTS)
Get PDFThe measuring method used to measure operator exposure during the filling process has been significantly improved by several innovative measures, such as a better washing program with less water, the operation of the washing machine with demineralized water, the use of stainless steel sieves for sample preparation and new overalls. In particular, during the test period, valuable experience was gained with the correct textile composition, the correct storage of the contaminated dosimeters and the evaluation of the measured data. The complex process could be made more efficient by new ideas in many places, so that a faster processing of the trials is possible. The measurement accuracy was improved or at least maintained depending on the dosimeter. Due to the independent filling of the tracer solution in PPP canisters, short storage times between filling and the beginning of the test could be realized, whereby the stability of the tracer and thus also the measuring accuracy are positively influenced. Especially in the variants without the CTS, the results show in some cases larger situation-dependent differences in the exposure of different operators. The execution of the tests should therefore be carried out by several operators with a sufficient number of repetitions. It can be deduced from the trial results that visors, laboratory gloves and underwear can largely be dispensed with when evaluating a CTS, since the proportion of these dosimeters in the total exposure is negligible. For overalls, the particular problem is that only a few valid measurements above the detection limit are available, although appreciable exposures may occur. On the other hand, the distribution of measurement results in protective gloves allows the derivation of a suitable standard reference value and is well suited as a basis for evaluating the filling systems. Due to the limits of quantification of the dosimeters, however, restrictions in the measuring methodology are set, which must not be disregarded when defining the test requirements.The measuring method used to measure operator exposure during the filling process has been significantly improved by several innovative measures, such as a better washing program with less water, the operation of the washing machine with demineralized water, the use of stainless steel sieves for sample preparation and new overalls. In particular, during the test period, valuable experience was gained with the correct textile composition, the correct storage of the contaminated dosimeters and the evaluation of the measured data. The complex process could be made more efficient by new ideas in many places, so that a faster processing of the trials is possible. The measurement accuracy was improved or at least maintained depending on the dosimeter. Due to the independent filling of the tracer solution in PPP canisters, short storage times between filling and the beginning of the test could be realized, whereby the stability of the tracer and thus also the measuring accuracy are positively influenced. Especially in the variants without the CTS, the results show in some cases larger situation-dependent differences in the exposure of different operators. The execution of the tests should therefore be carried out by several operators with a sufficient number of repetitions. It can be deduced from the trial results that visors, laboratory gloves and underwear can largely be dispensed with when evaluating a CTS, since the proportion of these dosimeters in the total exposure is negligible. For overalls, the particular problem is that only a few valid measurements above the detection limit are available, although appreciable exposures may occur. On the other hand, the distribution of measurement results in protective gloves allows the derivation of a suitable standard reference value and is well suited as a basis for evaluating the filling systems. Due to the limits of quantification of the dosimeters, however, restrictions in the measuring methodology are set, which must not be disregarded when defining the test requirements
Feuerbrand: Identifikation, Klonierung und funktionelle Charakterisierung korrelierender Gene bei Malus ×robusta
No full textInstitut für Züchtungsforschung an Obst
Die Pflanzenkrankheit Feuerbrand, welche durch das Enterobakterium Erwinia amylovora verursacht wird, stellt ein ernstes Problem für die Apfelproduktion weltweit dar. Eine erfolgreiche und zuverlässige Bekämpfung des Erregers ist bislang nur mit Streptomycinhaltigen Pflanzenschutzmitteln möglich, welche allerdings in Europa nur bedingt oder gar nicht eingesetzt werden dürfen. Besonders problematisch ist dies, da die meisten kommerziellen Apfelsorten anfällig gegenüber Feuerbrand sind. Die Entwicklung von neuen, feuerbrandresistenten Sorten ist damit eines der wichtigsten Ziele der Züchtung. Geeignete Resistenzquellen sind vor allem in Wildapfelarten zu finden, welche sich allerdings durch schlechte Fruchtqualität und geringe Fruchtgröße auszeichnen. Das Einbringen dieser Resistenzen mittels klassischer Züchtung ist ein sehr zeitaufwendiger Prozess, da die unerwünschten Eigenschaften durch Rückkreuzungen entfernt werden müssen. Molekulare Methoden wie die markergestützte Selektion können helfen, diesen Prozess zu beschleunigen. Hierfür ist es allerdings nötig die zugrunde liegenden Resistenzmechanismen und die beteiligten Gene zu kennen. Dies führte zum Ziel dieser Arbeit: die Identifikation, Klonierung und funktionelle Charakterisierung Feuerbrand relevanter Gene bei Malus ×robusta.
Neben der Identifikation neuer Gene, war es auch Aufgabe bereits bekannte Gene näher zu untersuchen. Eins dieser Gene mit großer Bedeutung für die Virulenz von E. amylovora ist der Effektor AvrRpt2EA. Innerhalb dieser Arbeit erfolgte zunächst die Sequenzierung des Effektors von 22 verschiedenen E. amylovora Stämmen mit unterschiedlicher Virulenz gegenüber Malus ×robusta 5 (Mr5). Ein Vergleich der Nukleinsäuresequenz zeigte einen Einzelnukleotid-Polymorphismus, welcher zum Austausch von Cystein zu Serin in der Proteinsequenz führte. Die zwei identifizierten Allele des Effektors wurden im weiteren für die Komplementierung der avrRpt2EA Deletionsmutante ZYRKD3-1 verwendet. Es folgten eine Virulenzanalyse und Real-Time qRT-PCR.
Da AvrRpt2EA homolog zu AvrRpt2 von P. syringae pv. tomato ist, war die Frage ob der Resistenzmechanismus ebenfalls ähnlich ist. In A. thaliana, interagiert AvrRpt2 mit dem Protein RIN4, wodurch das Resistenzprotein RPS2 aktiviert wird. Wenn es sich also um ähnliche Mechanismen handelt, müsste RIN4 auch im Genome von Mr5 zu finden sein. Außerdem wurde mittels Hefe-Zwei-Hybrid-System nach weiteren Interaktionspartnern gesucht und RIN4 mittels Western Blot detektiert.
Die Identifizierung von neuen Genen, als letzter großer Teil dieser Dissertation, erfolgte mit Hilfe einer differentiellen Transkriptomanalyse. Dafür wurde Mr5 mit der virulenten avrRpt2EA Deletionsmutante ZYRKD3-1 und dem avirulenten Wildstamm Ea1189 inokuliert. Der Vergleich des Transkriptoms ermöglichte die Identifizierung differentiell exprimierter Gene (DEG), welche direkt die Pathogenabwehr betreffen. Diese DEGs wurden Stoffwechselwegen zugeordnet, wobei der biotische Stress von besonderem Interesse war. Ausgewählte Gene wurden im Folgenden mit dem BioMark™ HD System näher untersucht.Institute for Breeding Research on Fruit
The bacterial plant disease fire blight caused by Erwinia amylovora is one of the main threats of apple production worldwide. Effective control can be only achieved by the use of the antibiotic streptomycin, but the application is restricted or even prohibited in Europe. Since most of the commercially successful apple cultivars are susceptible, fire blight resistance is one of the main goals of many apple breeding programs. Most described sources for fire blight resistance can be found among wild apple species, which, however, are characterised by bad fruit quality and small fruit size. The introgression of these resistances by classical breeding requires, therefore, several backcrosses to get rid of the undesired traits. Molecular methods like marker assisted breeding can help to speed up this process. However, it is essential to determine related genes and to understand the mechanism of resistance. This had let to the aim of the study: the identification, cloning and functional characterisation of fire blight related genes of Malus ×robusta.
Beside the identification of new genes, the study also focused on a closer description of already known genes. One gene with an essential role in the pathogenesis of fire blight is the effector AvrRpt2EA. First, the avrRpt2EA gene of twenty-two different E. amylovora strains differing in origin and isolated from different hosts was sequenced. Apart of one single nucleotide polymorphism (SNP), which resulted in an exchange from cysteine to serine in the amino acid sequence, all genes were identical. The two different alleles were later used for the complementation of the avrRpt2EA deletion mutant strain ZYRKD3-1. The established strains were evaluated by virulence analysis and Real-Time qRT-PCR.
AvrRpt2EA of E. amylovora is homologue to the effector AvrRpt2 of P. syringae pv. tomato. In A. thaliana AvrRpt2 interacts with the guard protein RIN4, which mediates resistance by activation of the R protein RPS2. The similarity between the two effectors raised the question, if there is a similar resistance mechanism between the two plant species. This would imply it is possible to identify RIN4 in Mr5. In addition to the genetic characterisation, the analysis was also focused on the proteomic level, which was done by a western blot and a yeast two-hybrid assay to prove protein-protein interactions.
Another major objective of this study was a RNA-seq analysis of the transcriptome of Mr5, to identify new genes related to the resistance mechanism. Therefore, Mr5 was inoculated with the virulent avrRpt2EA deletion mutant strain ZYRKD3-1 or with the non-virulent wild type strain Ea1189. The comparison of the transcriptomes enabled the identification of differentially expressed genes (DEGs), which are related to the disease response. The significant DEGs were assigned to pathways, whereby the focus was on genes belonging to the biotic stress. Selected genes were further analysed with the BioMark™ HD system
Characterization of physico-chemical and bio-chemical compositions of selected four strawberry cultivars
Get PDFThe physico-chemical and bio-chemical compositions of Hongyan, Tiangxiang, Tongzi Ι and Zhangji strawberries inChinawere analyzed. Their values were pH 3.42~3.73, titration acidity 0.63~0.79%, total soluble sugars 5.26~8.95 g/100 gfresh weight (FW), ascorbic acid 21.38~42.89 mg/100 gFW, total phenolics 235.12~444.73 mg/100 gFW, pectin 82.84~96.13 mg/100 gFW, total organic acids 874.30~1216.27 mg/100 gFW, Individual phenolic compounds other than anthocyanins 7.60~12.18 mg/100 gFW, free amino acids 13.35~32.66 mg/100 gFW, monomeric anthocyanins 4.47~47.19 mg/100gFW, antioxidant capacity of ·DPPH 14.14~18.87 and FRAP 7.97~10.54 equal to mg/100 gVc, polyphenol oxidase (PPO) activity 0~0.42 Abs/min, peroxidase (POD) activity 0.17~0.34 Abs/min and pectin methyl esterase (PME) activity 0.012~0.018 mL/min. Tongzi Ι was most suitable for food processing due to the highest titration acidity, total phenolics, pectin, total organic acids, monomeric anthocyanins, antioxidant capacity of ·DPPH and FRAP with lower PPO, POD and PME activity
Quality aspects in open-pollinated onion varieties from Western Europe
Get PDFCommercial onion breeders limit their selection criteria by focusing almost exclusively on conventional farming. This raises the demand for certain well known varieties, but lowers the general diversity available on the mainstream market. A way to maintain biodiversity is to preserve old open-pollinated varieties. Through their distinct aroma and flavor, these plants are again drawing the interest of farmers and consumers alike, making them a viable alternative to commercial varieties. To assess yield and quality aspects of West-European open-pollinated onions, we have evaluated nine varieties and compared them against two of their commercial, well-established counterparts. The study included onion production on the field in South-West Germany, evaluation of the quality and flavor parameters, as well as a trained sensory taste panel. Results showed high diversity in yield and chemical properties of the studied onion varieties, where two varieties in particular, stood out significantly. Compared to the control, the variety “Birnförmige” performed best and demonstrated high concentrations of fructan and pyruvic acid, both known to have curative and medicinal properties. On the other end of the spectrum, the variety “Jaune des Cévennes” demonstrated low dry matter content, low concentration of enzymatically-produced pyruvic acid and a high bolting percentage. The study also confirmed the link between individual quality components in onion bulbs, including the significantly negative correlation between minerals (such as calcium and magnesium) and fructan
Alkaloid content and essential oil composition of Mahonia breviracema cultivated under different light environments
Get PDFLight can affect the yields of alkaloid and essential oil in the synthesis of secondary metabolites directly or indirectly through plant growth. Despite Mahonia breviracema being an endemic medicinal species in China, research on the influence of light on production of alkaloid and essential oil is scarce. Thus, this research evaluated the influence of various lighting conditions on alkaloid yields and the composition and yields of the essential oils of M. breviracema. The results revealed significant differences in alkaloid yields, oil yieldsand chemical characteristics of M. breviracema grown in four different light intensities from 10 to 100% full sun shine. The total amount of alkaloids in plants under I30 and I50 was higher than that under I10 and I100 due to the higher biomass of plants. Oil yield of M. breviracema leaf increased linearly with the increase of lightincidence. Plants grown under I10 had less plastoglobuli, which coincided with the lowest oil yield (1.91 g kg-1). The plastoglobuli in chloroplasts increased when the irradiance levels increased, resulting in the highest oil yields under I100 (4.53 g kg-1). The principal components in the leaves of M. breviracema were hexadecanoic acid (10.54-72.19%) and α-ionone (1.25-42.39%). The highest hexadecanoic acid content was obtained under I50, followed by I30, and the highest α-ionone content was obtained under I100. Therefore, it is necessary to control the light environment to obtain raw materials with high quality
Drought affects size, nutritional quality, antioxidant activities and phenolic acids of Moringa oleifera LAM.
No full textTo observe variation in growth performance, antioxidant activities, and nutritional quality of Moringa oleifera, we exogenously applied benzyl amino purine (BAP), ascorbic acid, and moringa leaf extract (MLE) to moringa plants at three field capacity levels, 100, 75, and 40% in a completely randomized design with three replications. We observed a decrease in growth, chlorophyll a and b, total phenolic contents, antioxidant activities, crude protein, and mineral contents of moringa leaves at 100 and 40% field capacity in comparison with 75% field capacity. BAP best improved growth performance of moringa plants, improving shoot length, root length, number of leaves and photosynthetic pigments, followed by MLE at 75% field capacity, while moringa plants showed reduced growth at 40% field capacity which was increased by BAP and MLE foliar application. Maximum contents of gallic acid, p-coumaric acid and sinapic acid were found in moringa leaves when the plants were sprayed with ascorbic acid while p-hydroxybenzoic acid and caffeic acid were maximally increased under 75% field capacity when the plants were subjected to BAP followed by MLE. The lowest and highest crude protein, calcium, potassium, magnesium, and phosphorous contents were recorded under 40 and 75% field capacity, with MLE impro-ving these contents under both conditions. It can safely be concluded that moringa plants showed retarded growth under 100 and 40% field capacity, and that the effects of deficit in nutritional quality were mitigated by applying BAP and MLE. Among these two plant growth regulators, MLE can be preferred being a natural source
Seasonal effect on Moringa oleifera gaseous exchange and water use efficiency under diverse planting densities
Get PDFThe study on Moringa oleifera was conducted over twelve months during 2014-2015 to evaluate the impact of the growing season and varying planting densities on biomass yield and physiological at-tributes under dryland conditions. Trial was established at densities of 5000, 2500, 1667 and 1250 plants ha-1, with eight replicates. The increase in planting density led to an increase in biomass production. The monthly and seasonal data collected showed significant differences in net photosynthetic rate, transpiration, sub-stomatal CO2 and stomatal conductance. However, planting densities of M. oleifera had no significant effect on all the gaseous exchange parameters measured. The results further revealed that the amount of carbon dioxide assimilated by the tree is not attributable to photosynthetic and transpiration rates as well as stomatal conductance. Under water shortage condition and high temperature, M. oleifera used an adaptation strategy by reducing stomatal conductance and transpiration and hence increasing water use efficiency. Moringa oleifera thus has the ability to sequester carbon even under water stress conditions. The tree can therefore be recommended for planting at a relatively high density of 5000 plants ha-1 in many parts of Limpopo province where temperatures are favorable for improved farmers’ livelihoods as well as for climate change mitigation
