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Tomato fruits can be contaminated by saprophytic strains of Alternaria alternata which is the reason for the frequent occurrence of Alternaria toxins like alternariol, alternariol monomethylether or tenuazonic acid in these types of products. It was shown earlier that alternariol is a colonization factor for tomatoes. In the current analysis two different tomato genotypes were analysed by untargeted comprehensive two-dimensional gas chromatography mass spectrometry (GC×GC-MS). This analysis revealed clear differences in the metabolic profiles which were paralleled by differences in resistance towards Alternaria colonization. One of the genotypes was more resistant against A. alternata infection and contained high amounts of chlorogenic acid in contrast to the other genotype which was sensitive against infection. In in vitro analysis, chlorogenic acid reduced alternariol biosynthesis during the first days of growth of A. alternata. Expression analysis of the alternariol polyketide synthase gene, a key gene in the biosynthesis of alternariol, also revealed a temporal reduction in its expression in the first phases of growth. However by chromatographic analysis it could be demonstrated that chlorogenic acid was degraded over time. This degradation leads to a relief of inhibition resulting in an only temporal inhibition of alternariol biosynthesis. In vivo colonization experiments revealed that chlorogenic acid reduces colonization of tomatoes by A. alternata in a concentration dependent manner, which however is partly counteracted by the addition of alterariol.  相似文献   
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OBJECTIVE: To evaluate the ability of a questionnaire regarding the nonphysical aspects of quality of life (QOL) to differentiate sick and healthy dogs. ANIMALS: 120 dogs. PROCEDURE: The questionnaire was administered by telephone to owners of 120 dogs with appointments at a veterinary teaching hospital. A QOL score was calculated for each dog on the basis of questions relevant to the dog during the 7 days before the interview. Scores were recorded as bar graphs, and linear regression was used to examine the effect of health status and other variables on QOL score. Certain questions were eliminated post hoc, on the basis of defined criteria, and the analyses were repeated. RESULTS: Scores were similar for sick (range, 670% to 93.8%) and healthy (range, 68.0% to 89.8%) dogs. Environment (suburban vs rural) and duration of ownership were significant explanatory variables and accounted for 10.5% of the variation in the QOL score. Eleven questions were eliminated post hoc. The scores derived from the 2 versions of the questionnaire were highly correlated (r = 0.92). CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence that the QOL questionnaire could differentiate healthy dogs from sick dogs; environmental and owner factors appeared to be more important.  相似文献   
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Summary Fertilization and early seed development was studied in the variety Chinese Spring of common wheat (Triticum aestivum L.) after pollination with rye (Secale cereale L.) and selfing, and in the common wheat variety Hope after selfing. In all three combinations the first pollen tube reached the micropyle in about 40 min after pollination. When pollinated with rye the migration of the sperm nuclei to the egg cell and the polar nuclei was delayed by about an hour. In the subsequent development until 72 hours after pollination the average cellular and nuclear doubling times of embryo and endosperm were about 16 and 8 hours for the interspecific combination. 18 and 9 hours for Chinese Spring selfed and 20 and 12 hours for Hope selfed.  相似文献   
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Lange  Wouter  Wojciechowska  Barbara 《Euphytica》1976,25(1):609-620
Summary The crossing of common wheat (Triticum aestivum L.) with rye (Secale cereale L.), and especially the action of the crossability genes of wheat, was studied using the readily crossable wheat cv Chinese Spring (genotype kr 1 kr 1 kr 2 kr 2 >), the poorly crossable wheat cv Hope (genotype Kr 1 Kr 1 Kr 2 Kr 2 ), as well as the disomic substitution line of chromosome 5B of Hope into Chinese Spring (CS/Hope 5B, genotype Kr 1 Kr 1 kr 2 kr 2 ). By comparing crossability and actual fertilization, the poor crossability with rye of both cv Hope and the CS/Hope 5B substitution line was shown to result from absence of fertilization. Studies of pollen grain germination and pollen tube growth showed that the dominant alleles of the crossability genes manifested themselves through retardation and eventually inhibition of pollen tube growth at the style base and in the ovary wall. In Hope the growth of all pollen tubes was inhibited, whereas in CS/Hope 5B rarely fertilization was achieved. The recessive alleles of the crossability genes do not seem to have an influence on the growth of rye pollen tubes in wheat pistils.  相似文献   
5.
Proteins from pollen and leaves of parent forms and of a hybrid and an amphiploid Aegilops geniculata × S. cereale were subjected to a study by two-dimensional gel electrophoresis (2-DE). The majority of peptides found in the parents were revealed in the amphiploid pollen and the hybrid and amphiploid leaves, however, numerous parental peptides were absent both in hybrid and amphiploid. There were detected characteristic peptides in leaves of the hybrid as well as in the leaves and pollen of the amphiploid, which were absent in the material from both parents. 52 peptides were common for pollen and leaves of the amphiploid what corresponds to 14.2% and 25.7% of peptides in pollen and leaves, respectively. Three characteristic peptides were common for leaves and pollen of the amphiploid (MW 48.0 kDa in pH 5.9, MW 49.0 kDa in pH 6.9 and MW 22.0 kDa in pH 8.8). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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OBJECTIVE: To develop a preliminary discriminative questionnaire for assessment of nonphysical aspects of the quality of life (QOL) of pet dogs and evaluate the questionnaire's content validity, test-retest reliability, and internal consistency. STUDY POPULATION: Owners of 120 dogs. PROCEDURE: Each QOL question had 4 response options, representing descending levels of QOL that were equally weighted. A maximum of 38 items contributed to the QOL score. The questionnaire was administered by telephone to owners of dogs with appointments at a veterinary teaching hospital before the appointment. After the appointment, each dog was classified as sick or healthy by use of defined criteria; owners of healthy dogs had a second interview 3 to 4 weeks later. Test-retest reliability (kappa), internal consistency (Cronbach alpha), and respondents' comprehension were used as criteria for excluding an item. RESULTS: There were 77 sick and 43 healthy dogs. Twenty-two QOL questions had significant kappa values (0.11 to 0.91). The Cronbach alpha values for 5 domains of QOL ranged from 0.45 to 0.61, indicating that the domains had moderate internal consistency (homogeneity). The initial pool of 38 items was reduced to 27. CONCLUSIONS AND CLINICAL RELEVANCE: The questionnaire was designed to complement veterinary assessment of dogs' physical health. The questionnaire may be a useful tool in making decisions regarding dogs' QOL.  相似文献   
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The aim of this study was to determine the influence of selected halotolerant endophytic bacteria isolated from the roots of Salicornia europaea on the growth parameters of Beta vulgaris under different concentrations of salinity. Two endophytic strains were selected as inocula for the pot experiment: Pseudomonas sp. ISE-12 (B1) and Xanthomonadales sp. CSE-34 (B2). Surface-sterilised seeds were incubated in the bacterial inoculation suspensions before sowing and cultivated in a sterile mixture of sand and vermiculite (1:1). Six salinity treatments were taken into account: 0, 50, 100, 150, 200 and 300 mM NaCl. Inoculation of seeds with B1 and B2 positively affected germination percentage and germination index and shortened mean germination time, which led to a quickening of the growth stages of seedlings. After 42 days inoculated plants had, in general, a greater root length, higher dry biomass, lower tissue water content and lower specific leaf area compared with the control. While the positive effect of B2 bacteria was visible only at low salinity, strain B1 stimulated plant growth at higher salinities (200 and 300 mM NaCl). We suggest that the superior growth promotion observed for B1 may be related to the higher metabolic activity of these bacteria.  相似文献   
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