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81.
Jan Adamiak Arkadiusz Stępień Ewa Adamiak Dariusz Klimek 《Archives of Agronomy and Soil Science》2013,59(5):435-443
The effect of various fertilization methods on the simplified nutrients balance and changes of soil chemical features in crop rotation was estimated on the basis of 7-year (1994-2000) studies carried out on loess-based, sedimentary-gley, light-clay soil. Different fertilization methods were used: A - mineral fertilization; B - mineral and manure fertilization; C - straw, green manure and mineral fertilization; D - ecological compost and biodynamic preparation fertilization. Particular fertilization methods caused a significant differentiation of the nutrients balance. A positive phosphorus balance was found out in all the fertilization systems. It has been observed that the nitrogen and potassium carry-in with fertilizers was higher than the carry-out with crops in system B and C. A favorable calcium balance was achieved in systems C and D while a favorable magnesium balance - only in the ecologically fertilized systems (D). The changes of soil chemical features were only insignificantly dependent on the nutrient balance. After seven years of research, the contents of humus, phosphorus, potassium, magnesium and calcium increased while the soil reaction decreased in the soil of all the fertilized systems except the ecologically fertilized system. 相似文献
82.
Low tendency to tuber greening under light exposure is a desirable trait for marketing and processing potatoes. Knowledge of the genetic basis of this trait is limited. During two consecutive years tuber greening after 2-week light exposure was evaluated on 17 unselected diploid potato families obtained between parents with varying tuber-greening tendencies. Parents of these families and standard cultivars were evaluated at the same time. External and depth of tuber greening were examined after tubers were exposed to 2 weeks of light in the greenhouse followed by storage at 10 C, 4 C, and after reconditioning at 18 C. Families, storage conditions, and years significantly influenced tuber greening. Distribution of greening indicated it would be possible to select individuals with very low tuber-greening tendency. Generally, external tuber greening was more intense than depth of greening. External tuber greening increased during storage while depth of tuber greening decreased. A significant maternal effect on external tuber greening was found in one of the three sets of reciprocal crosses after storage at 4 C. Both general and specific combining abilities were important in the inheritance of tuber greening. The correlations between external and depth of tuber greening in most families were significant and relatively high. The results indicated that genotypes with low tendency to tuber greening can be selected in diploid families. 相似文献
83.
Summary The activities of lipolytic acyl-hydrolases (LAH) and lipoxygenases (LOX) were compared in stored tubers of potato cultivars
resistant (Acresta, Eba, Pentland Envoy) and susceptible (Kastor, Pana, Tasso) to post-wounding autolysis. In most cultivars,
LAH activities had reached a maximum by the end of December but in cv. Kastor activity continued to increase throughout the
storage period. LOX activities increased during most of the storage period except in cv. Tasso. The level of the fatty acid
hydroperoxides, assumed from determinations of the malonaldehyde level, also increased during storage.
This work was supported by Project CPBP 05.02.2.10 financed by the Polish Academy of Science. 相似文献
84.
In this study, an artificial neural networks (ANN) model was developed to predict the removal of a polycyclic aromatic hydrocarbon (PAH), namely, naphthalene from marine oily wastewater by using UV irradiation. The removal rate was used as model output and simulated as a function of five independent input variables, including fluence rate, salinity, temperature, initial concentration and reaction time. The configuration of the ANN model was optimized as a three-layer feed-forward Levenberg–Marquardt backpropagation network with log-sigmoid and linear transfer functions at the hidden (12 hidden neurons) and output layers, respectively. By considering goodness-of-fit and cross validated predictability, the ANN model was trained to provide good overall agreement with experimental results with a slope of 0.97 and a correlation of determination (R 2) of 0.943. Sensitivity analysis revealed that fluence rate and temperature were the most influential variables, followed by reaction time, salinity and initial concentration. The findings of this study showed that neural network modeling could effectively predict the behavior of the photo-induced PAH degradation process. 相似文献
85.
An Outlook on the Localisation and Structure-Function Relationships of R Proteins in <Emphasis Type="Italic">Solanum</Emphasis> 总被引:2,自引:2,他引:0
Erik Slootweg Wladimir Tameling Jan Roosien Ewa Lukasik Matthieu Joosten Frank Takken Jaap Bakker Aska Goverse 《Potato Research》2009,52(3):229-235
The co-evolution of plants and plant-pathogens shaped a multi-layered defence system in plants, in which Resistance proteins
(R proteins) play a significant role. A fundamental understanding of the functioning of these R proteins and their position
in the broader defence system of the plant is essential. Sub-project 3 of the BIOEXPLOIT programme studies how R proteins
are activated upon effector recognition and how recognition is conveyed in resistance signalling pathways, using the solanaceous
R proteins Rx1 (from S. tuberosum spp. andigena; conferring extreme resistance against Potato Virus X), I-2 (from S. lycopersicon; mediating resistance to Fusarium oxysporum) and Mi-1.2 (from S. lycopersicon; conferring resistance to Meloidogyne incognita) as model systems. The results obtained in this project will serve as a model for other R proteins and will be translated
to potential applications or alternative strategies for disease resistance. These include the modification of the recognition
specificity of R proteins with the aim to obtain broad spectrum resistance to major pathogens in potato. 相似文献
86.
Monika Slawiak Ewa Lojkowska 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(2):353-361
Primers for the PCR amplification of homologous genes encoding polyketide coronafacic acid and coronafacic ligase in the cells
of Pectobacterium atrosepticum SCRI1043 (BX950851) were developed to study the presence of these genes in the genome of Pectobacterium sp. and Dickeya sp. Coronafacic ligase catalyses the formation of coronatine from polyketide coronafacic acid and coronamic acid. Coronatine
is a toxin produced by Pseudomonas syringae and is one of the major virulence factors in this bacterium. This study using several strains of P. atrosepticum, P. carotovorum subsp. carotovorum and Dickeya sp. isolated in different countries, indicated that all strains of P. atrosepticum possess genes coding coronafacic acid (cfa gene cluster) and coronafacic ligase (cfl). However, these genes were present only in the genome of five out of 50 tested P. carotovorum subsp. carotovorum strains and two out of 34 strains of Dickeya sp. tested. The PCR products homologous to the sequence of cfa7 and cfl gene fragments were sequenced in order to check the level of homology between genes of P. atrosepticum, P. carotovorum subsp. carotovorum and Dickeya sp. The sequences of the gene fragments amplified from all P. atrosepticum strains were almost identical (100% and 99.97%, respectively). The homology of the sequences obtained for P. atrosepticum and sequences of five P. carotovorum subsp. carotovorum and two Dickeya sp. was lower, between 89.69% to 95.00% for the cfl gene fragment, and about 94% for the cfa7 gene fragment. 相似文献
87.
Veli-Matti Rokka Jari P. T. Valkonen Airi Tauriainen Leena Pietilä Renata Lebecka Ewa Zimnoch-Guzowska Eija Pehu 《American Journal of Potato Research》2000,77(3):149-159
Protoplasts were fused to produce somatic hybrids between a triploid (2n=3x=32-34) interspecific somatohaploid betweenSolanum brevidens Phil. andS. tuberosum L., and a dihaploid (2n=2x=24) anther-derived line ofS. tuberosum cv. Van Gogh. A total of 265 plants were regenerated from protoplast fusion derived calli and their hybridity was verified using fusion partner specific RAPD markers. These “second generation” somatic hybrids were aneuploid pentaploids (2n=5x=51-65) with a 2C DNA content ranging from 3.36 to 4.43 pg, which corresponded to the sum of the 2C values of each of the fusion partners (somatohaploid: 2.22 pg; and the dihaploid line of cv. Van Gogh: 1.87 pg). Most of the “second generation” somatic hybrids were vigorous, but variable in morphology. They were extremely resistant to PLRV and they had tolerance to PVY infection derived from the somatohaploid fusion partner. Even though most of the “second generation” hybrids tuberized, the tuber morphology was variable and most were poorly shaped. InErwinia soft rot resistance tests, the tubers showed higher level of resistance than the tetraploidS. tuberosum cultivars, the dihaploidS. tuberosum fusion partners and the hexaploid somatic hybrids betweenS. brevidens andS. tuberosum. The “second generation” somatic hybrids were all male sterile and failed to produce berries or seeds. 相似文献
88.
Michel JB Shen YK Aiden AP Veres A Gray MK;Google Books Team Pickett JP Hoiberg D Clancy D Norvig P Orwant J Pinker S Nowak MA Aiden EL 《Science (New York, N.Y.)》2011,331(6014):176-182
We constructed a corpus of digitized texts containing about 4% of all books ever printed. Analysis of this corpus enables us to investigate cultural trends quantitatively. We survey the vast terrain of 'culturomics,' focusing on linguistic and cultural phenomena that were reflected in the English language between 1800 and 2000. We show how this approach can provide insights about fields as diverse as lexicography, the evolution of grammar, collective memory, the adoption of technology, the pursuit of fame, censorship, and historical epidemiology. Culturomics extends the boundaries of rigorous quantitative inquiry to a wide array of new phenomena spanning the social sciences and the humanities. 相似文献
89.
90.