Horn J.,University of Stuttgart |
Lauster S.,University of Stuttgart |
Krenz B.,University of Stuttgart |
Kraus J.,Planta Angewandte Pflanzengenetik und Biotechnologie GmbH |
And 3 more authors.
Virus Research | Year: 2011
Beet curly top virus (BCTV) limits sugarbeet production considerably. Previous studies have shown that infections are associated with the generation of defective DNAs (D-DNA) which may attenuate symptoms. Transgenic sugarbeet lines were established carrying a partial direct repeat construct of D-DNA in order to examine whether they are useful as a means of generating tolerance against BCTV. Thirty four independent transgenic lines were challenged. Viral full-length and D-DNAs were monitored by polymerase chain reaction (PCR) or rolling circle amplification (RCA) and restriction fragment length polymorphism (RFLP). The differential accumulation of both DNA species was compared with symptom severity during the course of infection. RCA/RFLP allowed the discrimination of two D-DNA classes which were either derived from the transgenic construct (D0) or had been generated de novo (Dn). The statistical analysis of the results showed that the presence of D0-DNA correlated with increased symptom severity, whereas Dn-DNAs correlated with attenuated symptoms. © 2011 Elsevier B.V.
Nehls R.,PLANTA Angewandte Pflanzengenetik und Biotechnologie GmbH |
Kraus J.,PLANTA Angewandte Pflanzengenetik und Biotechnologie GmbH |
Matzk A.,PLANTA Angewandte Pflanzengenetik und Biotechnologie GmbH |
Jansen R.,KWS SAAT AG
Sugar Tech | Year: 2010
The development and market introduction of H7-1, the first commercially relevant transgenic sugarbeet, is described. A gene which sequence had been modified to code for a glyphosate-insensitive 5-enolpyrovylshikimate-3-phosphate synthase (EPSPS) was transferred to sugarbeet cells using Agrobacterium-mediated transformation. Plants were regenerated from such cells and were submitted to rigorous testing of their molecular, physiological, agronomic, and ecological properties. Data from these analyses constituted the basis for the legal deregulation of an elite transformation event. As results of this registration process permits for the cultivation of H7-1 have been issued in the USA, Canada, and Japan. For import purposes, food and feed utilization permits are in place in more than 15 countries, including the EU. H7-1 plants were used as starting material for the development of varieties adapted to the respective agronomical requirements of the designated cultivation areas, making extensive use of marker-assisted backcrossing (MABC) as one of the breeding tools. In addition to herbicide tolerance, numerous other transgenic traits are currently under development. Their prospects and technical concepts are briefly discussed. © 2011 Society for Sugar Research & Promotion.
Viefhues A.,University of Munster |
Heller J.,University of Munster |
Heller J.,University of California at Berkeley |
Temme N.,University of Munster |
And 2 more authors.
Molecular Plant-Microbe Interactions | Year: 2014
The thioredoxin system is of great importance for maintenance of cellular redox homeostasis. Here, we show that it has a severe influence on virulence of Botrytis cinerea, demonstrating that redox processes are important for hostpathogen interactions in this necrotrophic plant pathogen. The thioredoxin system is composed of two enzymes, the thioredoxin and the thioredoxin reductase. We identified two genes encoding for thioredoxins (bctrx1, bctrx2) and one gene encoding for a thioredoxin reductase (bctrr1) in the genome of B. cinerea. Knockout mutants of bctrx1 and bctrr1 were severely impaired in virulence and more sensitive to oxidative stress. Additionally, bctrr1 showed enhanced H2O2 production and retarded growth. To investigate the impact of the second major cellular redox system, glutathione, we generated deletion mutants for two glutathione reductase genes. The effects were only marginal; deletion of bcglr1 resulted in reduced germination and, correspondingly, to retarded infection as well as reduced growth on minimal medium, whereas bcglr2 deletion had no distinctive phenotype. In summary, we showed that the balanced redox status maintained by the thioredoxin system is essential for development and pathogenesis of B. cinerea, whereas the second major cellular redox system, the glutathione system, seems to have only minor impact on these processes. © 2014 The American Phytopathological Society.