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1.
The effects of no‐till versus conventional farming practices were evaluated on soft wheat functional and nutritional characteristics, including kernel physical properties, whole wheat composition, antioxidant activity, and end‐product quality. Soft white winter wheat cultivar ORCF 102 was evaluated over a two‐year period from three long‐term replicated no‐till versus conventional tillage studies in Oregon. Wheat from the no‐till cropping systems generally had greater test weight, kernel diameter, and kernel weight and had softer kernels compared with wheat from the conventional tillage systems. Compared with the conventional systems, no‐till whole wheat flour had lower protein and SDS sedimentation volume. Ash content as well as most minerals measured (calcium, copper, iron, magnesium, and zinc), except for manganese and phosphorus, were generally slightly lower in no‐till than in conventional wheat. Whole wheat flour from the no‐till cropping systems generally had slightly lower total phenolic content and total antioxidant capacity. Milling properties, including flour yield, break flour yield, and mill score, were not affected by tillage systems. Refined flour from no‐till systems had lower protein, SDS sedimentation volume, and lactic acid and sucrose solvent retention capacities compared with flour from conventional tillage. No‐till wheat generally had greater sugar‐snap cookie diameter than conventionally tilled wheat. In conclusion, no‐till soft white winter wheat generally had slightly reduced nutritional properties (protein, ash, most minerals, and total antioxidant content) compared with wheat from conventionally tilled systems, and it had equivalent or sometimes superior functional properties for baking cookie‐type products.  相似文献   
2.
Quantitative and qualitative modifications of tannins and anthocyanins in grape skin were investigated at different dates of harvest, from berries sorted on the basis of their density. Free anthocyanins accumulated until 170 g/L of sugars in pulp before undergoing a slight decrease. Changes in anthocyanin composition were observed with increasing sugar levels in the pulp that reflected structural differences between classes of anthocyanins. The proportion of methoxylated anthocyanins continued to increase in the skin as sugar accumulated while the proportion of coumaroylated anthocyanins initially increased (up to 200 g/L of sugars in the pulp) and then rapidly decreased. In comparison, no major quantitative nor qualitative change was observed for tannins, except for a slight increase of the mean degree of polymerization. Whatever the physiological stage of the pulp, the extraction yield of skin phenolics into hydroalcoholic solution for 5 h was lower than 77% for anthocyanins and 38% for proanthocyanidins. For both classes of compounds, no clear evolution in these extraction yields could be observed as sugars accumulated in pulp (from 162.6 to 275.0 g/L). Nevertheless, some structural features within each family of compounds significantly influenced extractability, for example, a lower extraction yield for coumaroylated anthocyanins and for tannins with a high degree of polymerization. Finally, no direct relationship could be found in extraction media between the amounts of all red pigments (measured in acidic conditions) and the color intensity at 520 nm (measured in wine-like model solutions).  相似文献   
3.
The role of different factors such as biological material (tissues, organs) and trophic condition (overfeeding or not) in the metal accumulation was studied in three genotypes of ducks (Pekin, Muscovy, and Mule) under breeding conditions. Results showed that overfeeding decreased the concentration in Cd, Cu, and Zn through the dilution process. In contrast, mercury concentration increased with this method. A relation between lipidic metabolism of genotypes and the distribution of this metal in biological material was found. Domestic ducks were little contaminated, but a low chronic contamination in Cd was observed, probably coming from the food. Due to the low levels of contamination observed in these breeding ducks, they can be considered as a good control for further contamination studies and comparison with accumulation levels recorded in the field. The impact of feeding condition on accumulation showed the importance of taking into account the life cycle of birds before studying their contamination and the impact of pollutants.  相似文献   
4.
Preliminary research to understand the flammability of 14 species of shrubs and 8 species of trees based on silica-free ash content was done in order to recognize which shrubs or trees are more flammable. The results show that the silica-free ash content of shrubs and trees leaves was greater than the stems ranging between 1.7% and 11.4% for leaf and 0.4% and 7.8% for the stems. The shrubsDicranopteris linearis, Imperata cylindrica, Eupatorium pubescens, Lantana camara, Eugenia sp.,Cliforia laurifolia, Pterospermum sp.,Hibiscus similis, Clidemia hirta andTrema orientalis must be considered when fire invades the plantation as well as the treeParaserianthes falcataria, Eucalyptus urophylla, Calliandra callothyrsus, andPeronema canescens.  相似文献   
5.
Chlorophyll fluorescence induction was used as a probe to detect herbicide detoxification in tolerant or susceptible wheat cultivars. Experimental conditions have been carefully examined for establishing detoxification kinetics of chlorotoluron and metribuzin, two photosystem-II-inhibiting herbicides. After a root treatment, leaves were cut, placed in glass tubes and maintained in the dark. The fluorescence induction rise was examined repeatedly and detoxification kinetics were established from these data for the same position on the individual leaves. The herbicide-dependent fluorescence rise decreased within hours in chlorotoluron-tolerant but not in susceptible Triticum aestivum cultivars. In contrast, no significant reversion could be detected after metribuzin application in both tolerant and susceptible cultivars of Triticum durum. Near the fluorescence-determined half-inhibition of photosystem II, linear detoxification kinetics were obtained in individual leaves, thus providing an accurate measurement of relative detoxification rates.  相似文献   
6.
7.
We studied the effects of two fertilization treatments (N and NPKCa) on wood nitrogen (N) isotope composition (delta(15)N), water-use efficiency (WUE) estimated by carbon isotope composition (delta(13)C) analyses, and ring width of trees in 80-year-old beech (Fagus sylvatica L.) stands in the forest of Fougères, western France. Four replicates were fertilized in two successive years (1973 and 1974), 20 years before core sampling. Unfertilized control trees displayed a decreasing delta(15)N trend with time. The N and NPKCa treatments both increased delta(15)N compared with the control treatment. Wood extraction by organic solvents enhanced the delta(15)N signal. Thus, N addition to the beech ecosystem, even in moderate amounts, could be traced back in tree-ring delta(15)N, suggesting that wood N isotope analysis is a promising tool for studying the long-term effects of N deposition on forests. Although WUE decreased for about 6 years after N fertilization, WUE in NPKCa-treated trees did not differ significantly from that in control trees. Results were similar whether based on cellulose or total wood delta(13)C analysis, suggesting that extraction of cellulose is not necessary when studying fertilization impacts on WUE. The NPKCa treatment had a large impact on radial growth, causing a significant long-lasting increase of 29% compared with the control treatment. Nitrogen alone did not change radial growth significantly.  相似文献   
8.
We tested whether synchronous, long‐term fluctuations in Atlantic bluefin tuna (Thunnus thynnus) trap catches, collected from the ancestral Mediterranean and Atlantic trap fishery, might be related to large‐scale environmental change. Nine time series of trap catches of more than 80 yr long were compared with long time series of three preselected environmental variables, i.e. the North Atlantic Oscillation (NAO), the Length of the Day Index (LOD, a proxy of the atmospheric circulation index) and the temperature. Spectral analyses of trap catches, LOD and temperature displayed similar spectra with peaks at low frequencies, whereas those of the NAO exhibited a broad band spectrum. Regression analyses and tests of correlation did not reveal any clear relationship between trap catches on the one hand and NAO and LOD on the other hand. In contrast, long‐term fluctuations in trap catches appear to be closely and negatively related to long‐term trends in temperature. Underlying processes that could explain such a relationship are discussed, with special focus on changes in migration patterns of the Atlantic bluefin tuna.  相似文献   
9.
Major sugar and carboxylic acid components in apricot flesh fruits were detected and quantified. Fifty-one genotypes including clones growing in France, Spain, Italy, Greece and USA, belonging to the INRA germ plasm collection has been evaluated. Principal component analysis (PCA) has been performed to study correlation among fruit quality measurements and to interpret relationships between genotypes as a tool for germ plasm characterization. A marked variation in malic and citric acid content has been observed and PCA revealed clusters of apricot genotypes for the malic/citric ratio content. A good correlation between sugar component and refractometer index (r = 0.83) has been detected. The wide range of diversity in malic and citric acid content in apricot germ plasm makes it possible to breed and select genotypes with improved flavour on the basis of superior phenotypes. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
10.
Constructed ponds are an important consideration in the conservation of wetland biota in agricultural landscapes. Twenty-two natural ponds and 22 adjacent constructed ponds (farm dams) were surveyed on the Southern Tablelands of New South Wales to compare patterns of use by frogs and develop frog conservation recommendations. Farm dams supported similar numbers of frog species to natural ponds, although differences in frog assemblage were observed between the pond types. Limnodynastes tasmaniensis and Uperolia laevigata were significantly more likely to occur at farm dams while L. peronii was more likely to occur at natural ponds. Results suggest waterbodies with high levels of emergent vegetation cover that lack fish are likely to support a high number of frog species, regardless of origin (i.e. natural or constructed). However, it is important for landholders to conserve natural waterbodies as these environments appear likely to support frog species that do not use farm dams.  相似文献   
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