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Robert F. Park Henriette Goyeau Friedrich G. Felsenstein Pavel Bartoš Friedrich J. Zeller 《Euphytica》2001,122(1):113-127
Pathogenicity data from surveys of Puccinia triticina (formerly P. recondita f. sp. tritici) conducted in western Europe in 1995 were analysed to compare the structure of regional populations of the pathogen. Many
of the populations differed in phenotypic diversity and pathotypic composition, even though they occurred within a single
epidemiological unit, suggesting that local factors may influence the establishment and propagation of individual pathotypes
in the regional populations. Neighbouring regions were more similar than distant regions, and all regions shared at least
one pathotype, except populations in northern Italy and Scotland. A high degree of similarity was found between populations
in northern France and Great Britain, providing strong evidence of free movement of inoculum between these regions. Resistance
genes were postulated for a selection of 91 wheat cultivars, representing those most commonly grown in western Europe in 1995.
Thirteen cultivars lacked detectable seedling resistance genes and the remaining 78 possessed from one to three resistance
genes; those detected were Lr1, Lr3a, Lr10, Lr13, Lr14a, Lr17b, Lr20, Lr26 and Lr37. The most commonly detected resistance gene was Lr13, which was present singly or in combination with other resistance genes in 48 cultivars (53%). The gene Lr14a was detected in 18 cultivars, Lr26 was present in 16 cultivars. The role of host selection in the composition of the regional populations of P. triticina in western Europe in 1995 was difficult to assess on the basis of the results obtained, since virulence data were not available
for Lr13 and Lr14a.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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The Triticum dicoccoides-derived wheat line Zecoi-1 provides effective protection against powdery mildew. F3 segregation analysis of Chinese Spring × Zecoi-1 hybrids showed that resistance in line Zecoi-1 is controlled by a single dominant gene. Amplified fragment length polymorphism (AFLP) analysis of bulked segregants from F3s showing the homozygous resistant and susceptible phenotypes identified eight markers, of which four were associated with the resistance allele in repulsion phase. Following the assignment of these four repulsion phase AFLP markers to wheat chromosome 2B with the aid of Chinese Spring nulli-tetrasomic lines, they were physically mapped in the terminal breakpoint interval 0.89 (2BL-6)–1.00 (telomere) of chromosome 2BL. Genetic and physical mapping of simple sequence repeat markers from the distal half of chromosome 2BL located the wild emmer-derived powdery mildew resistance gene distal of breakpoint 0.89 in deletion line 2BL-6. Based on disease response patterns, genomic origin and chromosomal location the resistance gene in Zecoi-1 is temporarily designated MlZec1. 相似文献
56.
P. Mayerhofer M. Weltschev A. Trukenmüller R. Friedrich 《Water, air, and soil pollution》1995,85(4):2687-2692
Damage to materials causes high economic losses in Europe. A large part of this damage can be attributed to the emissions caused by the energy and the transport sector. In the paper, the procedure for the economic assessment of material damages caused by SO2 and NOx emissions in Europe is described. Model and data requirements are outlined, and gaps and uncertainties of the quantification are discussed. Two types of results are presented: First, the marginal (additional) costs of damage to materials caused by an additional power plant are assessed. The analysis covers plants with different technologies. Results for the fossil power plants are in the range of 0.0062 to 0.12 mECU/kWh. In addition, the total economic material damage due to the present air pollution was assessed. It is in the range of 2.9 to 5.3 × 109 ECU/year. However, the analysis has many uncertainties. Most noteworthy are the material inventories and partially the damage functions and input data. 相似文献
57.
Zusammenfassung Bei 112 Linien 25 verschiedener BTT-Systeme erwies sich die genetische Stabilität der Systeme in den meisten Fällen als gut bis sehr gut, gemessen an der Frequenz disom-fertiler Rekombinanten. In speziellen Kreuzungstests ergaben sich Hinweise auf mögliche Stabilitätsstörungen durch Pollentransmission des Zusatzchromosoms nur bei einem von neun geprüften Systemen.Die Vitalität der trisomen Pflanzen bei den verschiedenen BTT-Systemen ist sehr unterschiedlich und von der jeweils vorliegenden Segmentzusammensetzung des Zusatzchromosoms abhängig. Bezogen auf diploide Pflanzen gibt es alle Übergänge von Subletalität bis hin zu annähernd normaler Vitalität. Leistungsfähige BTT-Systeme sind relativ selten und können mit ausreichender Wahrscheinlichkeit nur entwickelt werden, wenn von einer genügend breiten Basis von Translokations-undmsg-Linien ausgegangen wird.
Herrn Professor Dr. Dr. h. c. mult.H. Stubbe zum 85. Geburtstag gewidmet. 相似文献
Studies on the stability and viability in systems of balanced tertiary trisomy in barley
Summary The genetic stability of 112 stocks out of 25 different BTT systems proved to be, in most cases, good to very good, in terms of the frequency of disomic fertile recombinants. There is only rare indication of instability caused by pollen transmission of the extra chromosome: In special crossing tests only one out of nine BTT systems tested showed transmission.The viability of trisomic plants is very diverse in the different BTT systems and depends on the specific segmental composition of the extra chromosome. As compared with normal diploids there are all types of trisomics ranging from sublethal to nearly normal ones. Efficient BTT systems are comparatively rare. They can be developed with good expectation provided a sufficiently broad basis of translocation andmsg lines is used.
112 25 . - . . - , 9 . . , . , , , msg-.
Herrn Professor Dr. Dr. h. c. mult.H. Stubbe zum 85. Geburtstag gewidmet. 相似文献
58.
Strawberries were processed to juice, nectar, wine, and puree. For investigation of the antioxidant capacity as well as the contents of ascorbic acid, total phenolics and total anthocyanins, samples were taken after different stages of production to determine the effects of processing. The content of vitamin C was measured spectrophotometrically. The total phenolic content was analyzed by using the Folin-Ciocalteu method, and the amount of total anthocyanins was determined by using the pH-differential method. Two different methods-the trolox equivalent antioxidant capacity assay and the ferric reducing antioxidant power test-were used to determine the hydrophilic antioxidant capacity. This study showed the decrease of all investigated parameters within processing strawberries to different products. The content of ascorbic acid decreased with production time and processing steps, especially during heat treatment. The investigations on total phenolics in strawberry products proved fining to be a mild method to clarify berry juices and wines without removing high amounts of total phenolics. Fermentation did not lead to heavy losses of total phenolics, probably due to polymerization and condensation of monomer phenolics such as anthocyanins. Total anthocyanins and the hydrophilic antioxidant capacity decreased while using high temperatures. Anthocyanins also decreased considerably during the processing of wines, mainly caused by fermentation and pasteurization. 相似文献
59.
Schrader Gritta Hauser Barbara Bahadir Müfit Larink Otto 《Water, air, and soil pollution》2001,128(3-4):401-406
Water, Air, &; Soil Pollution - A filter dust of a waste incineration plant provided for underground disposal was elutriated with three different elutriation media possibly be found in... 相似文献
60.
In industrial areas, heavy metals may accumulate in forest soil organic horizons, affecting soil microorganisms and causing
changes in the chemical composition of the accumulated organic matter. The objectives of this study were to test the ability
of near-infrared spectroscopy (NIRS) to detect heavy metal effects on the chemical composition of forest soil O horizons and
to test whether NIRS may be used to quantitatively determine total and exchangeable concentrations of Zn and Pb (Znt, Pbt, Znex, Pbex) and other chemical and microbial properties in forest soil O horizons polluted with heavy metals. The samples of O horizons
(n = 79) were analyzed for organic C (Corg), total N and S (Nt, St), Znt, Pbt, Znex, Pbex, basal respiration (BR), microbial biomass (Cmic) and Cmic-to-Corg ratio. Spectra of the samples were recorded in the Vis-NIR range (400–2,500 nm). To detect heavy-metal-induced changes in
the chemical composition of O horizons principal components (PC1–PC7) based on the spectral data were regressed against Znt + Pbt values. A modified partial least squares method was used to develop calibration models for prediction of various chemical
and microbial properties of the samples from their spectra. Regression analysis revealed a significant relationship between
PC3 and PC5 (r = −0.27 and −0.34, respectively) and Znt + Pbt values, indicating an effect of heavy metal pollution on the spectral properties of the O horizons and thus on their chemical
composition. For quantitative estimations, the best calibration model was obtained for Corg-to-Nt ratio (r = 0.98). The models for Corg, Nt, and microbial properties were satisfactory but less accurate. NIRS failed to accurately predict St, Corg-to-St, Znt, Pbt, Znex, and Pbex. 相似文献