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1.
Summary Progeny lines of chromosome-doubled haploids from crosses between one winter and four spring barley varieties were analysed for winter hardiness and vernalization requirement in the field. About one quarter or less of the offspring lines required vernalization under field conditions showing that winter versus spring habit of growth is controlled by at least two pairs of genes. The vernalization requirement could be measured quantitatively by testing a few plants in a greenhouse after artificial cold treatment during germination. The individual winter lines tested required from two to seven weeks of vernalization in order to flower as early as possible. The cold treatment had no effect on the time of flowering in the spring lines.Winter hardiness varied from zero to 100% plant survival in the field. The majority of the lines requiring vernalization survived better than 90% and the survival of the rest was at least 60%. The winter survival of the spring lines varied from zero per cent (about one third of the lines) to 100%. Hence, it is possible to obtain lines of good winter hardiness without requirements for cold treatment. Conversely, a selection for vernalization requirement has a positive effect on winter hardiness.  相似文献   
2.
Flavor release from a mint-flavored chewing gum model system was measured by atmospheric pressure chemical ionization mass spectroscopy (APCI-MS) and sensory time-intensity (TI). A data analysis method for handling the individual curves from both methods is presented. The APCI-MS data are ratio-scaled using the signal from acetone in the breath of subjects. Next, APCI-MS and sensory TI curves are smoothed by low-pass filtering. Principal component analysis of the individual curves is used to display graphically the product differentiation by APCI-MS or TI signals. It is shown that differences in gum composition can be measured by both instrumental and sensory techniques, providing comparable information. The peppermint oil level (0.5-2% w/w) in the gum influenced both the retronasal concentration and the perceived peppermint flavor. The sweeteners' (sorbitol or xylitol) effect is less apparent. Sensory adaptation and sensitivity differences of human perception versus APCI-MS detection might explain the divergence between the two dynamic measurement methods.  相似文献   
3.
J. Torp  H. Doll  V. Haahr 《Euphytica》1981,30(3):719-728
Summary The grain yield and contents of the quantitatively predominant nutritional constituents of barley grain were determined in nine adapted spring barley varieties each grown at seven European locations with three or four replications.The largest variation in nutritional composition was due to different environmental conditions, but genotypic effects were also present. Interactions between genotype and environment were small. The average protein content at different locations varied from 8.1 to 14.7 per cent of the grain dry matter, and was not simply related to the amount of fertilizer-N applied.The nutritional composition of the grain was influenced by the grain yield level. The percentage of dietary fiber and protein decreased with increasing grain yield, but some varietal differences which were independent of the grain yield level could be established.The protein quality depended upon the protein level, as the protein contained more prolamin relatively to non-prolamin protein at high than at low protein levels. A difference between two varieties in the prolamin/non-prolamin ratio was consistent over a wide range of variation in protein content.  相似文献   
4.
The effect of parenteral penicillin treatment on the intestinal microbiota was determined by monitoring the phenotypic antimicrobial resistance among Escherichia coli in 19 calves (15 calves received treatment and four calves were healthy controls) and by examining changes in the fecal microbial community structure using molecular fingerprinting techniques in a subset of eight calves (five treated calves and three control calves). After five days of penicillin treatment an increased resistance to multiple unrelated antimicrobial agents, including non-β-lactams, was seen in E. coli from treated calves, and this was not seen in the controls. Automated ribosomal intergenic spacer analysis (ARISA) and terminal restriction fragment length polymorphism (TRFLP) revealed that penicillin treatment causes a significant variation in the microbial structure within an individual calf. The study shows that parenteral administration of penicillin has an impact on the composition of the fecal microbiota in calves, and on the antimicrobial resistance pattern of their fecal E. coli.  相似文献   
5.
Abstract

Several varieties of spring barley were tested in the greenhouse for resistance to leaf stripe (Drechslera graminea) following exposure to high levels of inoculum in the field, or by using the sandwich inoculation method. Pedigree analyses confirmed that most highly resistant varieties have obtained their resistance from a gene in the landrace Hordeum laevigatum via the variety ‘Vada’, while the remaining few may have it from the donor ‘Ricardo’, or from the cumulative effect of partial resistance. Experiments with fungicide seed treatment of ‘Golf’ and ‘Triumph’, which represent highly resistant, and susceptible genotypes, respectively, showed that the former always remained healthy, and does not benefit from seed treatment, whereas the latter requires treatment every year to avoid any seed loss.  相似文献   
6.
A dynamic headspace sampling method for isolation of volatiles in fish has been developed. The sample preparation involved freezing of fish tissue in liquid nitrogen, pulverizing the tissue, and sampling of volatiles from an aqueous slurry of the fish powder. Similar volatile patterns were determined by use of this sample preparation method and for samples chewed for 10 s. Effects of sampling time, temperature, and purge flow on level of volatiles were tested. Purging at 340 mL/min for 30 min at 45 degrees C was found to be optimal. Detection limits for a number of aldehydes were 0.2-2.7 microg/kg. Levels of volatiles are given for fresh salmon, cod, saithe, mackerel, and redfish.  相似文献   
7.
The multi-element (Ag, Al, Au, Ba, Bi, Ca, Cd, Co, Cr, Cs, Cu, Dy, Er, Fe, Ga, Gd, Ho, In, Ir, La, Lu, Mn, Mo, Nb, Nd, P, Pb, Pd, Pr, Pt, Rb, Re, Rh, Ru, Sb, Sc, Sm, Sn, Sr, Ta, Tb, Th, Ti, Tl, Tm, U, V, Y, Yb, and Zn) concentrations (microg/kg, fresh weight) in potatoes (Solanum tuberosum, Folva) were investigated in this study. The potatoes were grown in two fertilization practices; one with pig slurry and one with calcium ammonium nitrate at three levels of N fertilization (0, 60, and 120 kg of N/ha). The experiment field was located at the Riso National Laboratory Agronomy Farms in Roskilde, Denmark. High-resolution-inductively coupled plasma mass spectrometry (HR-ICPMS) was used for analyses of the samples. The effect of three levels of N fertilization on elemental concentrations of the crop are evaluated by use of discriminant partial least-squares regression (PLS). The results provide useful biological and nutritional information on potatoes.  相似文献   
8.
The behavior of antioxidants in emulsions is influenced by several factors such as pH and emulsifier type. This study aimed to evaluate the interaction between selected food emulsifiers, phenolic compounds, iron, and pH and their effect on the oxidative stability of n-3 polyunsaturated lipids in a 10% oil-in-water emulsion. The emulsifiers tested were Tween 80 and Citrem, and the phenolic compounds were naringenin, rutin, caffeic acid, and coumaric acid. Lipid oxidation was evaluated at all levels, that is, formation of radicals (ESR), hydroperoxides (PV), and secondary volatile oxidation products. When iron was present, the pH was crucial for the formation of lipid oxidation products. At pH 3 some phenolic compounds, especially caffeic acid, reduced Fe(3+) to Fe(2+), and Fe(2+) increased lipid oxidation at this pH compared to pH 6. Among the evaluated phenols, caffeic acid had the most significant effects, as caffeic acid was found to be prooxidative irrespective of pH, emulsifier type, and presence of iron, although the degrees of lipid oxidation were different at the different experimental conditions. The other evaluated phenols were prooxidative at pH 3 in Citrem-stabilized emulsions and had no significant effect at pH 6 in Citrem- or Tween-stabilized emulsions on the basis of the formation of volatiles. The results indicated that phenol-iron complexes/nanoparticles were formed at pH 6.  相似文献   
9.
The gene pool of indigenous Faroe Islands Cattle is strongly affected by crossing with Norwegian Red. In this study, the genetic structure in 191 animals representing five North European cattle breeds (Faroe Islands, Icelandic, Blacksided Troender, Western Fjord and Norwegian Red) and the genetic admixture in the contemporary Faroe Islands Cattle at the population and individual level were evaluated using 20 polymorphic microsatellite loci. Only 6.7% of the total genetic variation could be attributed to the differences amongst the breeds. The factorial correspondence analysis based on all allele frequencies could hardly reveal a divergence between Faroe Islands Cattle and Norwegian Red. In addition, a Neighbor‐Net tree constructed to examine the allocation of individuals of Faroe Islands Cattle and Norwegian Red provided a detailed interrelationship network for all the 72 animals. An estimation of the population admixture proportion showed a strong genetic contribution by Norwegian Red (47.3%) in the contemporary Faroe Islands Cattle. On the other hand, individual admixture analysis demonstrated that only seven of the individual Faroe Islands Cattle analysed, which also showed more traditional colour patterns, could be assigned to the Faroe Islands Cattle cluster, probably representing the breed's remaining purebred animals. Strategies for preserving the original native genes in Faroe Islands Cattle should be considered in order to prevent the breed from becoming extinct and to strengthen the breed's capability in future breeding programmes.  相似文献   
10.
B. Kjaer    V. Haahr  J. Jensen 《Plant Breeding》1991,106(4):261-274
Associations of 23 quantitative traits and 10 genetic marker characters were examined in 63 chromosome-doubled lines (DH-lines) derived from the F1- generation of a cross between an old and a modern spring barley variety. One fourth of the marker × trait combinations showed significant associations. More than two thirds of these associations were to earliness (heading date). Earliness was found to be controlled by two loci: the previously known eak locus and a new locus designated Ea. It is concluded that the associations of quantitative traits with the earliness loci were caused by pleiotropy. Associations were found between two absolutely linked C-bands on chromosome 3 and QTLs (quantitative trait loci) for lodging, straw diameter, and length of top internode of the straw. The three loci on chromosome 5, eak and the two linked powdery mildew loci, Mla9 and Mlk, were associated with a possible QTL for magnesium concentration in grain. Association to the C-band on chromosome 6 suggests QTLs for TGW (thousand grain weight), straw diameter and magnesium concentration in grain. Locus Estl on chromosome 3 was not associated with any of the quantitative traits.  相似文献   
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