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111.
Xiaorong Wu Anne Maier Tingting Wu Ningbo Li Jeff R. Pedersen Donghai Wang 《Cereal Chemistry》2013,90(3):198-203
To evaluate the ethanol production performance of waxy sorghum hybrids and the effects of location and harvest year on ethanol yield, samples of four waxy sorghum hybrids collected from two Nebraska locations (Mead and Lincoln) in both 2009 and 2010 were tested for ethanol production in a dry‐grind process. No significant difference (P = 0.216) in starch contents was observed among the four hybrids, but starch contents of the hybrids were significantly affected by growth location (P = 0.0001) and harvest year (P = 0.0258). Location, hybrid, and harvest year all had significant effects on ethanol fermentation efficiency in the dry‐grind process. Lincoln sorghum samples showed higher (P = 0.022) ethanol fermentation efficiency (90.4%) than did Mead sorghum samples (90.0%). Sorghums harvested in 2010 had higher (P < 0.001) ethanol fermentation efficiency (91.1%) than those harvested in 2009 (89.3%). The 2009 sorghum flours had more amylose‐lipid complexes than the 2010 samples did, and amylose‐lipid complexes as previously reported had adverse effects on ethanol fermentation. Residual starch contents in distillers dried grains with solubles (DDGS) were significantly affected by hybrid and harvest year (P < 0.0001), but we observed no difference in protein content in DDGS from the four hybrids. 相似文献
112.
Birthe Pedersen Dr Bjørn O. Eggum 《Plant foods for human nutrition (Dordrecht, Netherlands)》1983,33(1):51-61
Wheat was milled into flours having extraction rates between 100 and 66%. The nutritive value of the various fractions was studied by chemical analyses and in balance trials with rats. The concentration of essential nutrients decreased when the extraction rate was lowered. The lysine content (g/16 g N) e.g. was 2.52 in whole wheat, but only 2.18 in the 66% extraction flour; however, only a slight reduction in biological value was found. The content of minerals was reduced to 30% of that in whole wheat, and the apparent zinc absorption and retention expressed in absolute values, were significantly higher from the flours of high extraction than from the more refined flours, in spite of a much higher phytate content in whole wheat and lightly milled flours. It could be concluded that milling of wheat into highly refined flours not only preclude considerable amounts of nutrients from human consumption, but the remaining flours have a much poorer nutritive value than flour made from whole wheat. 相似文献
113.
Birthe Pedersen Dr B. O. Eggum 《Plant foods for human nutrition (Dordrecht, Netherlands)》1983,33(4):267-278
Brown and milled rices were prepared from rough rice, and the nutritive value of the rices was studied by chemical analyses and in balance experiments with growing rats. The concentration of essential nutrients decreased with the degree of milling, but the energy density of brown and milled rices was similar. In the highly refined white rice the protein content was reduced to 86% and the mineral content to 23% of corresponding levels in brown rice. The zinc concentration was halved. The amino acid composition was rather unaffected by the degree of milling, but the lysine concentration was slightly lower in white rice than in brown rice. Milling was accompanied by an increase in true protein digestibility and a corresponding decrease in biological value. Thus net protein utilization of the different rices was remarkably uniform. A total of 33% of the utilizable protein and 22% of the digestible energy in brown rice was removed during milling. Rats fed rough, brown and lightly milled rices were unable to maintain their femur zinc concentration; deposition of calcium and phosphorus also appeared to be affected. Factors present in the outer part of the rice kernel interfere strongly with zinc utilization. Phytate and/or fibre are not solely responsible for this effect. Unless rice was milled into highly refined white rice, zinc status of rats was adversely affected. The results suggest that zinc might be a limiting factor in rice-based diets. 相似文献
114.
Birthe Pedersen Dr B. O. Eggum 《Plant foods for human nutrition (Dordrecht, Netherlands)》1983,33(4):313-326
Low-tannin sorghum was milled into flour with extraction rates between 100 and 64%. The nutritive value of the flours was studied by chemical analyses and in balance experiments with growing rats. The effects of amino acid supplementation was also examined. In general, the content of essential nutrients decreased when the extraction rate was lowered, but the content of fibre, tannins and phytate was also significantly reduced by milling. The digestibility of energy as well as protein was high, but the protein quality was poor, especially in flours of low extraction. Amino acid supplementation improved protein utilization and weight gain considerably. Femur zinc concentration was significantly depressed in the rats fed the amino acid supplemented diets, and sorghum seems to be a poor source of available zinc, in particular when it is highly refined. The poor zinc availability may be attributed to the high content of phytate. 相似文献
115.
Factor analysis of the data from experiment one with fertilization of ‘Spartan’ apples using various levels of nitrogen, phosphorus, and potassium and their interactions showed significances between ethylene and potassium, soluble solids and potassium, acidity and phosphorus, ethylene and phosphorus, and between ethylene and nitrogen. Factor analysis of data from experiment two with twenty apple cultivars showed that maturation time and ethylene were positively associated, whereas ethylene was inversely related to acidity that is reduced during the apple fruit maturation, and soluble solids are produced during apple fruit maturation. The effects of potassium on ethylene could be through promotion of enzyme activation, promotion of protein synthesis and increased solute transport in the xylem and phloem. Production of ethylene through soluble solids could be due to increased synthesis of the amino acid cysteine that is precursor of ethylene that may be extended to synthesis of other amino acids. The decreasing concentration of malic acid during fruit maturation may be due to increasing rates of several enzymes involved in the citric acid and glyoxylate cycles that are delivering precursors to synthesis of amino acids and porphyrins. The significant relationships between soluble solids and potassium and between acidity and phosphorus may increase the synthesis of nucleic acids and improve energy supply through adenosine phosphates. The significance between ethylene and nitrogen may also increase synthesis of amino acids, proteins and enzymes. On this basis it may be concluded that the three major minerals nitrogen, phosphorus and potassium are very important for apple fruit maturation because they may be involved in several biochemical processes. 相似文献
116.
Background
In the androdioecious nematode Caenorhabditis elegans virtually all progeny produced by hermaphrodite self-fertilization is hermaphrodite while 50% of the progeny that results from cross-fertilization by a male is male. In the standard laboratory wild type strain N2 males disappear rapidly from populations. This is not the case in some other wild type isolates of C. elegans, among them the Hawaiian strain CB4856.Results
We determined the kinetics of the loss of males over time for multiple population sizes and wild isolates and found significant differences. We performed systematic inter- and intra-strain crosses with N2 and CB4856 and show that the males and the hermaphrodites contribute to the difference in male maintenance between these two strains. In particular, CB4856 males obtained a higher number of successful copulations than N2 males and sired correspondingly more cross-progeny. On the other hand, N2 hermaphrodites produced a higher number of self-progeny, both when singly mated and when not mated.Conclusion
These two differences have the potential to explain the observed variation in male persistence, since they should lead to a predominance of self-progeny (and thus hermaphrodites) in N2 and, at the same time, a high proportion of cross-progeny (and thus the presence of males as well as hermaphrodites) in CB4856. 相似文献117.
Joshua H. Wong Tsang Lau Nick Cai Jaswinder Singh Jeffrey F. Pedersen William H. Vensel William J. Hurkman Jeff D. Wilson Peggy G. Lemaux Bob B. Buchanan 《Journal of Cereal Science》2009
Although a principal source of energy and protein for millions of the world's poorest people, the nutritional value of sorghum (Sorghum bicolor L. Moench) is diminished because of low digestibility of grain protein and starch. To address this problem, we analyzed the properties of two sorghum lines that have a common pedigree but differ in digestibility. Consistent with results based on a ruminal fluid assay, the protein and starch of one line (KS48) was more thoroughly digested than that of the other (KS51) using in vitro assays based on pepsin and α-amylase. The indigestibility of KS51 relative to KS48 was shown to be due to (i) a greater abundance of disulfide-bonded proteins; (ii) presence in KS51 of non-waxy starch and the accompanying granule-bound starch synthase; and (iii) the differing nature of the protein matrix and its interaction with starch. The current findings suggest that each of these factors should be considered in efforts to enhance the nutritional value of sorghum grain. 相似文献
118.
Hanne ?sterg?rd Kristian Kristensen Hans O. Pinnschmidt Preben Klarskov Hansen Mogens S. Hovm?ller 《Euphytica》2008,163(3):391-408
For low-input crop production, well-characterised varieties increase the possibilities of managing diseases and weeds. This
analysis aims at developing a framework for analyzing grain yield using external varietal information about disease resistance,
weed competitiveness and yield potential and quantifying the impact of susceptibility grouping and straw length scores (as
a measure for weed competitiveness) for predicting spring barley grain yield under variable biotic stress levels. The study
comprised 52 spring barley varieties and 17 environments, i.e., combinations of location, growing system and year. Individual
varieties and their interactions with environments were analysed by factorial regression of grain yield on external variety
information combined with observed environmental disease loads and weed pressure. The external information was based on the
official Danish VCU testing. The most parsimonious models explained about 50% of the yield variation among varieties including
genotype-environment interactions. Disease resistance characteristics of varieties, weighted with disease loads of powdery
mildew, leaf rust and net blotch, respectively, had a highly significant influence on grain yield. The extend to which increased
susceptibility resulted in increased yield losses in environments with high disease loads of the respective diseases was predicted.
The effect of externally determined straw length scores, weighted with weed pressure, was weaker although significant for
weeds with creeping growth habit. Higher grain yield was thus predicted for taller plants under weed pressure. The results
are discussed in relation to the model framework, impact of the considered traits and use of information from conventional
variety testing in organic cropping systems. 相似文献
119.
120.
Main branches of Abies nordmanniana Spach. were examined through their first growth season from subapical buds around the leader bud to fully expanded shoots. Plagiotropism was evident in branch orientation, which was almost horizontal, as well as in the orientation of buds developing on the branches. Auxin transport capacity was predominantly basipetal (> 90%) and consistently higher in the middle part of the branch than in the distal and proximal ends. Auxin transport capacity was higher on the dorsal side of the branch during the short initial hyponastic growth phase, but the difference disappeared when the branch became horizontal. No dorsal-ventral differences could be detected in young horizontal branches in concentrations of indole acetic acid, cytokinins, gibberellins or abscisic acid. Branch orientation was unaffected by decapitation of the leader apex or by decapitation and replacement with exogenous auxin. However, decapitation resulted in a less plagiotropic bud arrangement on the branches, and auxin application to the leader bud scar counteracted this effect. Thus, a signal originating in the stem seems to be involved in regulating branch bud positioning, whereas the horizontal branch orientation must rely on a different mechanism, presumably autonomic within the branch. 相似文献