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Apeldoorn, Netherlands

Grosch R.,Leibniz Institute of Vegetable and Ornamental Crops | Schneider,IRS | Kofoet A.,Leibniz Institute of Vegetable and Ornamental Crops | Feller C.,Leibniz Institute of Vegetable and Ornamental Crops
Journal of Phytopathology | Year: 2011

The impact of continuous cropping of lettuce on the disease dynamics of bottom rot and genotypic diversity of the causal pathogen Rhizoctonia solani AG 1-IB was studied over 3 years with two crops per year within a field naturally infested with R. solani the pathogen. This field had not had lettuce cultivated in it for 7 years. The disease incidence (DI) and disease severity (DS) were assessed at each harvest and mapped. Surprisingly, a high DI was already observed in the first crop of year one of this field study. In addition, the pathogen was also found to be evenly distributed. Severely infected plants occurred mainly in patches, and the position varied between crops. A significant increase in DS was already observed in the second year, and both temperature conditions and continuous cropping influenced the DS on average over time. Rhizoctonia isolates were randomly collected from the first crop in 1999 and the sixth crop in 2001. The genotypic diversity within the subgroup of R. solani AG 1-IB was analysed by BOX-PCR genomic fingerprinting and the aggressiveness of isolates by bioassay. The fingerprints revealed a high level of genotypic diversity within the AG 1-IB field population. However, continuous cropping was found not to have an impact on genotypic diversity and aggressiveness. © 2010 Blackwell Verlag GmbH. Source


Kobayashi S.,KCCT | Ohtsubo Y.,Kinki University | Iwasaki H.,Bando Chemical | Kobayashi Y.,BL Autotec Co.ltd | Takamori T.,IRS
9th IEEE International Symposium on Safety, Security, and Rescue Robotics, SSRR 2011 | Year: 2011

Rescue robots have to work in a variety of terrains, so the drive train of these robots must be robust against load changes including impulsive forces like collisions. To address this issue, the super- robust HFD actuator was developed. Also robots have to have special mechanisms to enter rooms by opening doors. A door opening system composed of a manipulator unit and suction mechanical unit for search robots was developed. The specific features of these robot components are reported in this paper. © 2011 IEEE. Source


Laufer D.,Institute of Sugar Beet Research | Nielsen O.,NBR | Wilting P.,IRS | Koch H.-J.,Institute of Sugar Beet Research | Marlander B.,Institute of Sugar Beet Research
European Journal of Agronomy | Year: 2016

Yield and nitrogen (N) use efficiency (NUE) are important traits for the evaluation of crops used for renewable energy production. Contrary to other bio-energy crops, data on NUE are not available for beet crops from the Beta genus for high yielding conditions of northwestern Europe. Thus, our study aimed to provide such information for one current representative of the cultivar groups sugar and fodder beet. Field experiments were conducted with six mineral fertilizer N doses (0-200 kg N ha-1, 40 kg steps) at one site in Germany (DE), The Netherlands (NL) and Denmark (DK) in 2010 and 2011; each combination of site and year (DE10, DE11, NL10, NL11, DK10, DK11) was evaluated as distinct environment.The environments strongly differed in yield (dry matter, sugar), N uptake, harvest indices and N-utilization efficiency (NUtE) parameters. Increasing the fertilizer N dose increased dry matter yield and sugar yield in the environments NL10, NL11, DK10 and DK11, but not at DE10 and DE11. Harvest indices decreased with increasing fertilizer N dose in the environments NL10, NL11, DK10 and DK11 only, which were characterized by a 70-110kg Nha-1 lower N uptake at zero fertilizer N than DE10 and DE11. The N uptake continuously increased while NUtE decreased with increasing fertilizer N dose at all environments. When regarding environmental and fertilizer N effects, yield was neither related to harvest indices nor NUtE.Despite several significant interactions between environment and cultivar, the data clearly reveal that yield, sucrose concentration in taproot dry matter, total plant N uptake, NUtE and apparent fertilizer N recovery were considerably higher for sugar beet (SB) than for fodder beet (FB). Contrastingly, harvest index on taproot dry matter basis and N harvest index were higher in FB than in SB, while harvest index for sugar was similar. An improved harvest index was obviously not the cause for the higher sugar yield of SB compared to FB, while sucrose concentration in taproot dry matter was clearly favourable for SB. Although SB crops incorporated more N into the leaves than FB, NUtE was considerably higher in SB, especially when focusing on sugar instead of dry matter production. In conclusion, SB offers a higher potential for producing bio-energy per unit of arable land with less N use related greenhouse gas emissions per unit of energy gain than FB. © 2015 Elsevier B.V. Source


Bornemann K.,Institute of Sugar Beet Research | Bornemann K.,U.S. Department of Agriculture | Hanse B.,IRS | Varrelmann M.,Institute of Sugar Beet Research | Stevens M.,Innovation Center
Plant Pathology | Year: 2015

Rhizomania, one of the most devastating diseases in sugar beet production, is caused by Beet necrotic yellow vein virus (BNYVV) and transmitted by Polymyxa betae. Previously, disease control was possible by cultivation of sugar beet hybrids carrying a major resistance gene Rz1, which restricts virus accumulation in taproots and suppresses symptom development. Over the last few years, BNYVV strains with four RNA components have arisen, which are able to overcome Rz1-mediated resistance. All strains described so far possess an A67V amino acid exchange within the RNA3-encoded P25 pathogenicity factor. In this study, BNYVV was isolated from Rz1 plants, collected in the United Kingdom, the Netherlands and Germany, displaying patches of strong rhizomania symptoms. Sequencing of the coat protein and P25 gene of three isolates showed 100% nucleotide sequence identity and detected AYPR as the P25 tetrad amino acid composition. The ability of this strain to accumulate to higher levels in young plants of Rz1 resistant but not in Rz1 + Rz2 resistant genotypes was initially demonstrated in a greenhouse assay in natural field soil from the Netherlands. This strain was loaded into a virus-free P. betae population and compared to reference strains. The AYPR strain retained its resistance-breaking ability in the Rz1 genotypes and displayed replication at a higher rate compared to the Rz1-resistance-breaking P type. The strain origin is unclear and it remains speculative whether the occurrence at different geographic locations is the result of independent selection or displacement of infested soil. © 2015 British Society for Plant Pathology. Source


Blott R.,Space Enterprise Partnerships | Koppel C.,KopooS Consulting Ind | Jansen F.,German Aerospace Center | Ferrari C.,ISIS R and D | And 3 more authors.
Proceedings of the International Astronautical Congress, IAC | Year: 2013

The Disruptive Technologies for Power and Propulsion (DiPoP) Study reviewed advanced space technologies for large interplanetary missions of interest to Europe taking account of European industry capabilities. These included large robotic missions to outer planets, asteroid deflection missions and longer term interplanetary manned missions. These missions involve high speed increments, generally beyond the capability of chemical propulsion (except if gravitational swing-by can be used). For missions beyond Mars orbit fission nuclear energy sources become competitive with solar panels. Both fission nuclear thermal (NTP) and nuclear electric propulsion (NEP) were considered. NTP high thrust levels may offer the only means of asteroid deflection by direct impact following late detection. However with sufficient advanced warning the greater control from NEP relatively low thrust deflection over a period of time is a lower risk option. For NEP two electrical power levels have been considered: 30 kW and 200 kW. The lowest power level (30 kW) is more suited to surface energy source (Moon or Mars manned base) or to relatively small automatic platforms. The 200 kW power level is more suited to heavy robotic missions, including asteroid deflection. The public acceptance of these new technologies has been analysed, showing the necessity to provide safe ground testing facilities as well as a mission scenario excluding re-entry of an activated space nuclear reactor. Copyright © 2013 by the International Astronautical Federation. All rights reserved. Source

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