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51.
This paper presents the levels of copper and zinc determined in a total of 66 samples of the most widely consumed varieties of white and red grapes in Spain, as well as those of 60 samples of grape juice (39 from white varieties and 21 from red ones) chosen from the main commercial brands in the country. Atomic absorption spectroscopy was used as analytical technique, with electrothermal atomization after digestion of the sample with HNO(3)-H(2)O(2) for grapes and with HNO(3) for grape juice. The mean Zn contents obtained (0.0462 mg/100 g in grapes and 0.0460 mg/100 mL in grape juice) are lower than those provided by most of the more commonly used food composition tables. The mean Cu contents were 0.0515 mg/100 g in grapes and 0.0063 mg/100 mL in grape juice. On the basis of these data and the official data on consumption of grapes and grape juice in Spain, the contribution of both products to the recommended daily intake of zinc (15 and 12 mg/day for healthy adult men and women, respectively) is estimated to be approximately 0.1%, whereas for Cu, this supply represents rather more than 0.25% of the established ESADDI (1.5-3 mg/day in adults). The growing popularity of these products in recent years, on the basis of its nutritional properties and beneficial effects, requires additional data, and the present findings are of potential use to food composition tables.  相似文献   
52.
×Tritordeum (Ascherson et Graebner, an amphiploid between Triticum turgidum conv. durum and Hordeum chilense), and chromosome substitution lines of tritordeum where chromosomes 2 H ch or 3 H ch H. chilense were replaced with chromosome 2 D of T. aestivum or 3 H v chromosome of H. vulgare, respectively, were used to assess the effect of specific chromosomes on the rachis. ×Tritordeum has brittle rachis while the 2 D(2 H ch) and 3 H v (3 H ch) substitution lines have non-brittle rachis. Both lines also have compact spikes, a character highly desirable for the improvement of tritordeum threshability. Different combinations of 2 D and 3 H v translocations were developed in tritordeum. In this article we present information on the identification and characterisation of all these introgression lines by the fluorescent in situ hybridisation.  相似文献   
53.
To estimate family BLUP breeding values and the heritability of body weight at harvest size (BW) in the Pacific white shrimp, Penaeus (Litopenaeus) vannamei, an experiment was conduced using information from two farm units of a Mexican hatchery and two shrimp population densities at each location. Data consisted of 12,658 shrimps that were siblings from 48 sires and 77 dams with a nested dam-sire structure. Shrimps were individually weighed at an average age of 130 days post-hatching. BW phenotypic mean (S.D.) was 18.2 (2.4) g, with values ranging from 8.4 to 30.0 g. Data were analyzed using univariate and multivariate models that considered BW within location by density pond environment as a different trait and included or not a common full-sib effect (c). The multivariate animal model included fixed effects of days from hatching and sex. For univariate models that included c effects, BW heritability (S.E.) estimates ranged from 0.24 (0.14) to 0.35 (0.18) across environments (heritability was zero in one environment). For multivariate models (excluding the environment with zero heritability) the heritabilities increased and ranged from 0.37 (0.06) to 0.45 (0.09). Standard errors of heritabilities and c effects were both drastically reduced in the multivariate analysis. Pairwise genetic correlations between environments were from 0.80 (0.08) to 0.86 (0.04). These differences may be indicative of genotype-environment interaction for BW at 130 days post-hatching. Statistical problems found to separate c from additive genetic effects both in univariate models were reduced using multivariate models. Correlation between family raw phenotypic means and family BV means from the multivariate analysis was 0.93 indicating a rather low risk of miss selecting superior families if BLUP solutions were neglected using replicated environment data. It is also concluded that use of incorrect statistical models or unreplicated data may lead to biased or inaccurate estimates of genetic parameters in shrimp breeding programs.  相似文献   
54.
A chickpea F2 population of 593 plants derived from the intraspecific cross ILC3279 × WR315 was genotyped for markers closely linked to quantitative trait loci (QTLs) for ascochyta blight resistance (QTLAR1 and QTLAR2 located on linkage group 4 and QTLAR3 on linkage group 2). All the markers located on linkage group 4 exhibited strongly distorted segregation with respect to the expected Mendelian inheritance, towards the male parental line. This skewed segregation was also observed in a second F2 population of 50 plants derived from the same cross, confirming the presence of a region of distorted segregation on this linkage group and its heritability. The most skewed markers were SC-Y17 and TA72, which were tightly linked to each other, indicating that they may both be closely associated with the genetic factor responsible for segregation distortion in chickpea. To attempt to explain the non-Mendelian segregation, by identifying factors to which it could be attributed, three different chi-square tests were carried out to test different hypotheses using the data obtained from examining co-dominant markers associated with segregation distortion. According to our results, the distorted segregation could be caused by gametophytic factors that affect either male or female gametes. Pollen fertility and meiosis were also analysed to determine their relationship with segregation distortion; however, these not seem to be inducing factors in the non-Mendelian segregation reported in this study.  相似文献   
55.
Enzymatic defense responses and protection against Phytophthora nicotianae were studied in tobacco plants treated with chitosan of different molecular weights (MW) and degrees of acetylation (DA). The concentration and mode of chitosan application affected enzymatic induction in tobacco leaves. β-1,3-Glucanase (EC 3.2.1.6) activity required 10 times the polymer concentration relative to the oligochitosan mixture to induce the highest activity above control when treated by foliar spray, indicating the influence of molecular weight in this response. PAL (EC 4.3.1.5) and POD (EC 1.11.1.6) activities increased above control as a result of the influence of polymer degree of acetylation when treatments were applied by foliar spray. A higher DA favored PAL activity, whereas a lower DA induced higher POD activity. Using an in vitro bioassay, it was found that the three chitosan compounds caused a reduction of the infection index of P. nicotianae in tobacco plants that was dependent on elicitor concentrations. There was a significant relationship between the reduction of the infection index and an increase in PAL activity when chitosan was applied by foliar spray and by substrate drench to the plant rhizosphere. These results demonstrate the influence of chitosan physico–chemical properties in plant-induced resistance and the relevance of particular responses in plant protection against pathogens.  相似文献   
56.
Diuron ( N '-[3,4-dichlorophenyl]- N,N -dimethylurea) is one of the most frequently used herbicides in olive groves in Spain and other Mediterranean countries. The main objective of this work was to investigate the effect of the dissolved organic carbon (DOC) from a commercial humic amendment, derived by composting the liquid waste of the olive-mill process (LF), and a solid residue from the olive oil production industry (AL) on the sorption and leaching behaviour of diuron in soil. For this purpose, a clay and a sandy soil were selected. Soil sorption coefficients of diuron increased with LF (32%) and AL (76%) amendment in the sandy soil, whereas sorption decreased in the clay soil upon amendment, especially in the case of the liquid LF (52%). The DOC from LF and AL is composed of very poorly humified molecules, which are strongly sorbed onto the clay soil and thus compete with diuron for the same sorption sites. Dialysis experiments revealed that diuron forms stable complexes with DOC from LF and AL. Leaching of diuron in columns of the sandy soil treated with the organic amendments caused earlier breakthrough and maximum concentration peaks at fewer pore volumes when compared with leaching with 0.01 m CaCl2. Competition between diuron and DOC molecules for sorption sites and diuron–DOC interactions can both account for the enhanced leaching of diuron.  相似文献   
57.
The herbicide norflurazon was encapsulated in ethylcellulose (EC(40)) microspheres by the solvent evaporation technique to obtain controlled release formulations. The kinetics of release of the active ingredient into the aqueous solution from different preparations was determined. It was found that the percentage release of the incorporated herbicide was a function of the composition and formation conditions of the formulations (amount of emulsifying agent, EC(40)/herbicide ratio, stirring speed, and percentage of pore-forming agent). The percentage of the herbicide release was related to the properties of the different microspheres obtained, such as particle size distribution, herbicide loading, or surface morphology. The release percentage depended inversely on the particle size of the microspheres and directly on the content of active ingredient and emulsifying and pore-forming agents. An empirical equation was used to fit the herbicide release data, indicating that the release of norflurazon from the various formulations is controlled by a diffusion mechanism. The time taken for 50% of the active ingredient to be released into water (T(50)) was calculated, showing a wide variation among the different preparations (0.95-16.4 days).  相似文献   
58.
59.
The present study aims to characterize the main morphological changes occurring on the bovine ruminal papillae during pre- and postnatal development. Light microscopic observations of the ruminal wall from bovine fetus (3 to 9 month fetal age) and from crossbreed (Holstein-Frisian) calves (5 to 60 days-old) were analysed. The results suggest that the postnatal papillary development corresponds mainly to a fully actualization of the differentiation pattern already developed at the prenatal stage.  相似文献   
60.
Aliphatic and aromatic hydrocarbons, fatty acids and heavy metals (Pb, Cu, Ni, Zn, Fe and Cd) were analyzed in bulk deposition samples at two locations within the metropolitan area of Caracas, Venezuela. One of the sampling sites was located in the center (urban site, 1), while the other was in the outkirts of the city (rural site, 4). In general, a higher flux was observed for the deposition of pollutants at site 1 than at site 4. These fluxes showed relatively large short-term variations, while the long-term integrated deposition was found to be relatively constant throughout the sampling period. Wet deposition did not affect the flux of most of the pollutants studied, with the exception of Pb and the fatty acids of an anthropogenic origin.  相似文献   
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