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1.
The influence of vine training and sunlight exposure on the 3-alkyl-2-methoxypyrazines contents in musts and wines was studied by means of two previously reported methods based on headspace solid-phase micro-extraction. Experimental samples were monitored throughout grape ripening and wine making. 3-Isobutyl-2-methoxypyrazine, 3-sec-butyl-2-methoxypyrazine and 3-isopropyl-2-methoxypyrazine were identified. The 3-isobutyl-2-methoxypyrazine content decreased throughout grape ripening in all of the sample types studied. After 1 day of maceration with the skins, there was an increase, but after racking, no further increase was observed. No significant differences between samples were found during grape ripening. Wines from goblet-trained vines, however, contained significantly less 3-isobutyl-2-methoxypyrazine. Clusters protected from sunlight since the beginning of the veraison resulted in wines with a significantly lower content of this compound than the control samples.  相似文献   

2.
Present study reported the variation in electrophoretic seed subfraction (albumins, globulin A, globulin B, glutelins) patterns in some Lathyrus species collected from their natural habitats different localities in Turkey. Electrophoretic data were documented by using a gel documentation system (Bio-Rad, USA) and analysed by using Quantity 1-D analysis software and also the dendograms were formed with 4.0% tolerance in UPGAMA (Unweighed Pair-Group Arithmetic Mean). The differences among species were observed and all seven species were clearly identifiable from the protein patterns. The dendograms obtained from cluster analysis of seed storage proteins data showed examined species have displayed a number of distinct relationships. According to our results, it seems justified to recommend a wider use of electrophoretic analysis of seed storage proteins in taxonomic investigations of leguminous plants.  相似文献   

3.
The genus Arachis is divided into nine taxonomic sections. Section Arachis is composed of annual and perennial species, while section Heteranthae has only annual species. The objective of this study was to investigate the genetic relationships among 15 Brazilian annual accessions from Arachis and Heteranthae using RAPD markers. Twenty-seven primers were tested, of which nine produced unique fingerprintings for all the accessions studied. A total of 88 polymorphic fragments were scored and the number of fragments per primer varied from 6 to 17 with a mean of 9.8. Two specific markers were identified for species with 2n = 18 chromosomes. The phenogram derived from the RAPD data corroborated the morphological classification. The bootstrap analysis divided the genotypes into two significant clusters. The first cluster contained all the section Arachis species, and the accessions within it were grouped based upon the presence or absence of the ‘A’ pair and the number of chromosomes. The second cluster grouped all accessions belonging to section Heteranthae.  相似文献   

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5.
Multivariate methods, including principal component, cluster and discriminant analyses, were used to assess the patterns of morphological variation and to group 415 sorghum accessions for 15 quantitative characters. The first five principal components explained 79% of the total variation with plant height and days to 50% flowering being the most important characters in the first principal component. Cluster analysis grouped the accessions into ten clusters. A greater proportion of accessions of similar adaptation zones and accessions from regions of origin with similar agro-climatic conditions were grouped together. Moreover, discrimination of accessions was more pronounced when discriminant analysis was based on zone of adaptation rather than regions of origin. Based on the observed patterns of variation, it is concluded that the morphological variation in the material studied is structured by environmental factors. The implications of the results for plant breeding and germplasm conservation programmes arediscussed.  相似文献   

6.
The objectives of this work were to investigate the nutritional and physicochemical characteristics as well as the functional properties of quinoa protein isolates (QPI) from different varieties, and to determine their potential use of such protein isolates in food products. Proteins were isolated by isoelectric precipitation at pH 5 from quinoa flour, and the QPI had a protein percentage of over 85%. The comparison of the flours and QPI electrophoretic profiles indicated that the extraction method allowed isolating practically all proteins of each variety. All the varieties analyzed had high lysine content, compared with cereals, and the essential amino acid content of Bolivian varieties was higher than varieties from Peru. The pH value affected the solubility and foaming capacity, and the magnitude of effects depended on the variety. Cluster analysis showed a strong influence of variety source and amino acid composition on protein physicochemical and functional properties; samples from Bolivia (cluster 2) were characterized as having the highest thermal stability, oil binding capacity, and water binding capacity at acid pH; samples from Peru (cluster 1) had the highest water binding capacity at basic pH and foaming capacity at pH 5. QPI presented a potential as an alternative vegetable protein for food application, in particular for vegetarian and vegan diets.  相似文献   

7.
Sequence-related amplified polymorphism (SRAP) marker was employed to analyze genetic relationships of 10 Chinese, 11 Japanese varieties of persimmon and its 6 relatives. Twenty out of 72 primer combinations could amplify clearly and consistently. Just only one primer set could discriminate all the genotypes used in this study. The genetic relationships were analyzed using unweighted pair-group method of arithmetic average cluster analysis (UPGMA) and principal coordinated analysis (PCOA). The results showed: Chinese varieties were grouped into two clusters, while the Japanese varieties were grouped into one cluster with two subgroups. The persimmon relatives were clustered together. Probably, Chinese and Japanese Pollination-constant and Non-astringent (PCNA) persimmons had different genetic background. ‘Eshi No.1’ from Hubei province was close to Male type 6. ‘Xiangxitianshi’ from Xiangxi municipality, Hunan province, had a high similarity coefficient with ‘Maekawa-Jirou’ and was clustered in the Japanese varieties group, indicating that ‘Xiangxitianshi’ maybe close to the Japanese variety in terms of genetic background. The Chinese Pollination-constant and Astringent (PCA) and PCNA persimmons were not distinctly distinguished implying that the non-astringent trait of Chinese PCNA type might result from the PCA type.  相似文献   

8.
Morphological variability of four wild species, one semi-cultivated and one cultivated species of Theobroma L., indigenous to Brazil and introduced in the Bahian cocoa-growing region, was characterized based on 35 quantitative and 13 qualitative traits. T. cacao, which shows a great diversity of conserved germplasm and many published references for morphological characterization, besides of being one of the most cultivated species in Theobroma, was used for comparison as reference species. Sample size was defined for each organ evaluated and individual data set related to leaf, flower, fruit and seed analyzed by a multivariate approach. The studied species showed a large variation for all morphological traits evaluated. T. grandiflorum (Willd. ex Spreng.) Schum. and T. bicolor Humb. et Bonpl. showed the highest means for quantitative variables but were very divergent from each other considering flower and qualitative traits. These were the only species that presented similar number of seeds in comparison with T. cacao. A species with smaller means for most traits was T. obovatum Klotzsch ex Bernoulli. The four wild species show white seeds while T. cacao shows purple ones. Multivariate analysis of variance indicates significant differences between Theobroma species for individual or grouped morphological fruit traits. The results from a cluster analysis were, in a general way, congruent with botanical classification. The statistical analysis performed here was useful to identify a great variability among evaluated traits and to distinguish the most divergent variables from Theobroma species. This work provided an important contribution to morphological characterization of polymorphic traits from different organs of Theobroma species, which can help breeders in the future on the direction of interspecific crosses attempts.  相似文献   

9.
A combination of gas chromatography (GC) and chemometrics was evaluated for its ability to differentiate between apple juice samples on the basis of apple variety and applied heat treatment. The heat treatment involved exposure of 15 mL juice samples for 30 s in a 900 W domestic microwave oven. The chromatographic results were subjected to two chemometric procedures: (1) partial least squares (PLS) regression and (2) linear discriminant analysis (LDA) applied to principal component (PC) scores. The percent correct classification of samples were obtained from PLS and LDA in terms of separation on the basis of apple variety and applied heat treatment. PLS gave the highest level of correct classification of the apple juice samples according to both variety and heat treatment, 92.5% correct classification in each case. When LDA was performed on the PC scores obtained from GC analysis, 87.5% and 80% of samples were correctly classified according to apple variety used and applied heat treatment, respectively.  相似文献   

10.
《Cereal Chemistry》2017,94(3):560-567
Thirty hard red spring (HRS) wheat cultivars released between 1910 and 2013 were analyzed to determine how they cluster in terms of parentage and HPLC analysis of gliadins and unreduced proteins. Markers for reduced height genes were assessed to determine associations between semidwarfism and protein composition, as well as quality characteristics. In terms of parentage, the clusters formed were grouped according to release year and semidwarfism. Farinograph development time and stability showed significant (P ≤ 0.05) differences between clusters, indicating improvement of mixing characteristics over time. Flour ash content was significantly different (P ≤ 0.05) between clusters, indicating improved milling quality. The clusters based on the gliadin reverse‐phase HPLC peak binary data did not group cultivars according to release year and the semidwarf characteristic. However, cultivars were grouped according to year in the absorbance area based dendrogram. The clusters based on absorbance area of size‐exclusion HPLC showed significant (P ≤ 0.05) differences for release year, the semidwarf characteristic, and farinograph stability. Overall, the results indicate that the introduction of reduced height genes accompanied the improvements of dough mixing and breadmaking quality characteristics, without altering the composition of gliadin proteins over the last 100 years of HRS wheat breeding.  相似文献   

11.
To assess diversification of indica rice, fingerprinting of 42 Indian rice varieties (Oryza sativa L) and one accession of O. brachyantha Chev. et Roehr. was taken up using amplified fragment length polymorphism (AFLP). Six primer combinations of PstI and MseI were used for this purpose. On denaturing polyacrylamide sequencing gel, on average 41 scorable AFLP bands were obtained of which 81% were polymorphic. Each variety revealed a distinct fingerprint. Data were scored on the basis of presence and absence of bands and cluster analysis was performed using Dice similarity coefficients. The resultant dendrogram showed four major clusters and traits. Some varieties especially landraces revealed more polymorphism and unique loci. Such study will be a valuable tool for proper choice of parents in mapping populations or breeding programs to produce heterotic several inexplicable minor clusters. Some varieties were grouped according to parentages of the cross while some were grouped according to physiological combinations apart from providing a characteristic fingerprint.  相似文献   

12.
Changes in the physicochemical composition of wine vinegars produced by submerged culture system and aged in wood were followed. Five Sherry wine vinegars and a model vinegar solution were aged in six new American oak butts of 16.6 L capacity. A total of 24 phenolic compounds were monitored during the maturation study (24 months), along with other physicochemical parameters (total extract, acidity, residual alcohol and total phenolic index). Multivariate statistical analysis was applied to the data. From the sixth month on, significant changes were produced in most of the phenolic compounds, mainly aromatic aldehydes and 5-(hydroxymethyl)-2-furaldehyde. When all the phenolic compounds were considered as variables, cluster analysis grouped samples according to the wine substrate employed in the elaboration of vinegars under study. Within each subcluster, samples are arranged according to their aging status when phenolic compounds accounting significative changes at 180 days of aging are considered. Discriminant functions were constructed from the phenolic compounds data set. The validity of these functions was tested using 13 samples of aged commercial Sherry wine vinegars and 25 unaged vinegars. A total of 97.4% of the test samples was correctly classified within its respective group.  相似文献   

13.
Fifty-four accessions of Phaseolus vulgaris cultivated in Spain and representing a broad variability for this country, were studied together with 30 samples of wild forms of American origin. Two reference cultivars (from the Andes and Mesoamerica) plus two outgroups (P. coccineus and Vigna unguiculata) were also included. RAPD analysis of DNA leaf extracts were carried out with four selected primers. We also studied morphological characters of the seeds and the phaseolin electrophoretic patterns. Multivariate analysis with the UPGMA method using RAPD data clustered the samples in four groups and, comparing with morphological data and phaseolin types, showed that the Spanish cultivars were mainly of Andean origin. Nevertheless, occurrence of introgression in Spain and the consideration of the country as a second center of variability for beans can also explain the obtained results.  相似文献   

14.
A DNA-based method has been applied to the identification of several musts and wines using microsatellite markers. DNA was extracted from the solid phases of sixteen monovarietal and five multivarietal musts (mixtures of two musts down to a 4:1 proportion) and they were genotyped at seven microsatellites through a multiplex PCR reaction and automated fluorescent detection. PCR multiplexing was successful in monovarietal musts, but should be used with caution with at least some markers and in multivarietal musts. The same extraction and detection methods were unsuccessfully applied to the solid and liquid phases of five monovarietal commercial wines, even after using different concentration procedures. Nucleic acids presence was then studied in a recent must, during the fermentation process, and during the subsequent steps of winemaking. Genotyping was possible in the resulting experimental wine until decanting, when the particles in suspension were removed. These results suggest that wine authentication through DNA analysis is not possible in commercial wines, in the tested conditions.  相似文献   

15.
The effects of hyperoxygenation on Chardonnay white musts and the influence of subsequent storage on the corresponding wines have been evaluated. Attention was focused on the color characteristics, phenolic and volatile composition, and sensorial analysis, not previously reported in conjunction. On the one hand, the hyperoxygenation treatment provoked a significant decrease in the concentration of virtually all phenolic compounds in musts, young wines, and one-year-stored wines. In addition, a higher resistance to browning was observed in stored wines derived from hyperoxygenated musts. Different storage conditions (light and dark) produced significant differences in the 2-S-glutathionylcaftaric acid derivatives amounts. On the other hand, significant differences were observed in the volatile composition of wines due to the hyperoxygenation treatment, such as a decrease in the isoamylic alcohols concentration, acetaldehyde, and β-damascenone, even after storage under different conditions. Finally, Chardonnay white wines derived from hyperoxygenated musts had higher banana odor and lower herbaceous and flowery notes.  相似文献   

16.
17.
The physical chemistry characteristics of honey are directly related to floral origin and, as a result, to the production region. There are some available methods that can determine the botanical or geographical origin of honey such as the free amino acids profile analysis. This paper reports data on the free amino acid composition, determined by reversed-phase high-performance liquid chromatography UV detection on 56 honey samples from three different Argentine regions, with characteristic apiarian flora. To evaluate if the quantified amino acid could be used to verify the geographical or botanical origin of honey, statistical analyses were performed. The cluster analysis showed that samples were grouped in clusters related to sampling regions and more strictly to apiarian flora around apiaries. Each cluster appears associated, in accordance with the principal component analysis, to high or low concentrations of different amino acids.  相似文献   

18.
Summary Patterns of morphological diversity were examined in relation to geographical origins of 157 accessions of wild Lupinus angustifolius from the Aegean region using multivariate techniques. Genetic diversity was extremely large for most morphological traits, with significant variation detected among localities in Greece and within and between collection sites for some traits. Canonical variates and correlation analysis showed that early flowering, tall and large-seeded accessions were associated with warm winters and drier climates in southern Greece. Thirteen groups of accessions were identified by hierarchical cluster analysis of 19 morphological traits, accounting for 81 % of genotype and 41 % of genotype x trait sums of squares. The distinguishing features of these groups were clarified by principal coordinates analysis. Two groups, with very desirable agronomic characteristics, originated from the Dhodhekanisos Islands (Kos, Leros, Patmos) in the south-eastern Aegean: these had rapid and tall growth, prolific podding on the main stem, pods high off the ground, many upper lateral branches, large leaves, pods and seeds, and high seed yield. Accessions from the Kikladhes Islands of the central Aegean were extremely variable and those from Naxos Island were represented in 9 of the 13 groups. Accessions from northern Greece grouped together as later flowering, shorter, and smaller-seeded types, but some accessions from the southern Greek Islands were grouped with the northern mainland types. This study identified regions in Greece, such as the south-eastern islands, where further collection may be warranted for traits of obvious agronomic value for domesticated L. angustifolius. Extreme morphological variability occurs within and between collection sites, and between localities in Greece.  相似文献   

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20.
Engrafted cuttings of the variety Rkaciteli on stocks B?×?R Cober 5BB and R?×?R 101-14, having endured open and covered stratification on different substrates, were planted in a polyethylene glasshouse on four artificial substrates after the postplanting preparation. The complex effect of the stock variety was examined, as well as the effects of the stratification methods and the substrates on the yield of engrafted vines. The characteristics of the regeneration of the engrafted cuttings during the stratification were established. The optimal substrates for stratification of the transplants and the growing of engrafted vines in glasshouses were defined.  相似文献   

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