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301.
Julio Cesar Raposo Almeida Jean-Paul Laclau José Leonardo de Moraes Gonçalves Jacques Ranger Laurent Saint-André 《Forest Ecology and Management》2010
Contrasting responses of Eucalyptus trees to K fertilizer applications have been reported on soils with low K contents. A complete randomized block experiment was set up in Brazil to test the hypothesis that large atmospheric deposits of NaCl in coastal regions might lead to a partial substitution of K by Na in Eucalyptus physiology and enhance tree growth. Treatments with application of 1.5, 3.0, 4.5 kmol K ha−1 (K1.5, K3.0, K4.5, respectively) as KCl, 3.0 kmol K ha−1 applied as K2SO4, 3.0 kmol Na ha−1 (Na3.0) as NaCl commercialized for cattle feeding, and a mixture of 1.5 kmol K + 1.5 kmol Na ha−1 (K1.5 + Na1.5) were compared to a control treatment (C) with no K and Na applications. All the plots were fertilized with large amounts of the other nutrients. 相似文献
302.
Bowei Ye Ravi P.Singh Chan Yuan Demei Liu Mandeep S.Randhawa Julio Huerta-Espino Sridhar Bhavani Evans Lagudah Caixia Lan 《作物学报(英文版)》2022,(2):490-497
Leaf rust(LR) and stripe rust(YR) are important diseases in wheat producing areas worldwide and cause severe yield losses under favorable environmental conditions when susceptible varieties are grown. We determined the genetic basis of resistance to LR and YR in variety Borlaug 100 by developing and phenotyping a population of 198 F6 recombinant inbred lines derived from a cross with the susceptible parent Apav#1. LR and YR phenotyping were conducted for 4 and 3 seasons, respectively, at CIMMYT research stations in Mexico under artificial epidemics. Mendelian segregation analyses indicated that 3–5 LR and 2 YR genes conferred resistance in Borlaug 100. Lr46/Yr29(1 BL), Yr17(2 AS) and Yr30(3 BS) were present in the resistant parent and segregated in the RIL population based on characterization by molecular markers linked to these genes. When present alone, Lr46/Yr29 caused average 13% and 16% reductions in LR and YR severities, respectively, in RILs. Similarly, Yr17 and Yr30 reduced YR severities by 57% and 11%, respectively. The Yr30 and the Yr17 translocation were also associated with 27% and 14% reductions, respectively, in LR severity, indicating that the 3 BS and 2 AS chromosomal regions likely carry new slow rusting LR resistance genes, temporarily designated as Lr B1 and Lr B2, respectively. Additive effects of Yr30*Yr17, Yr29*Yr17 and Yr29*Yr30 on YR and LR were significant and reduced YR severities by 56%,55%, and 45%, respectively, and LR severities by 34%, 40%, and 45%, respectively. Furthermore, interaction between the three genes was also significant, with mean reductions of 70% for YR and 54% for LR severities. Borlaug 100, or any one of the 21 lines with variable agronomic traits but carrying all three colocated resistance loci, can be used as resistance sources in wheat breeding programs. 相似文献
303.
Julio Beltrame Daleprane Tatiana Silveira Feijó Gilson Teles Boaventura 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(1):1-5
The aim of this study was to evaluate the protein quality of organic and genetically modified soy by feeding specific diets
to rats. Three groups of Wistar rats (n = 10) were used, and each group was named according to the food that they ate. There was an organic soy group (OG), a genetically
modified soy group (GG), and a control group (CG). All animals received water and diet ad libitum for 455 days. At the end of this period, the weight of the GG group was the same as that of the OG, and both were higher
than CG. Protein intake was similar for the OG and GG, which were significantly lower (p < 0.0005) than the CG. The growth rate (GR) of the rats, albumin levels, and total levels of serum protein were comparable
for all groups. Hematocrit (p < 0.04) and hemoglobin (p < 0.03) for the OG and GG were less than the CG. Although the OG and GG demonstrated reduced hematocrit and hemoglobin, both
types of soy were utilized in a way similar to casein. This result suggests that the protein quality of soy is parallel to
the standard protein casein in terms of growth promotion but not hematological indicators. 相似文献
304.
Ritva Repo-Carrasco-Valencia Alexander Acevedo de La Cruz Julio Cesar Icochea Alvarez Heikki Kallio 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(2):94-101
Cereals provide a good source of dietary fibre and other important compounds with nutritional potential, such as phenolic compounds, antioxidants, minerals and vitamins. Although native Andean cereals are known to have high nutritional value, their minor components have not been studied thoroughly. In this study, two varieties of a native Andean crop, kañiwa (Chenopodium pallidicaule), were investigated as sources of dietary fibre and specific antioxidant compounds. Two products, an extrudate and bran, were also prepared and their functional properties and bioactive compounds were determined. Both varieties were rich in total dietary fibre and lignin, and the phenolic components analyzed had high antioxidant activity. The extrudates had good functional properties, such as degree of gelatinization, sectional expansion index and water solubility index; the bran was high in bioactive compounds, such as total phenolics. In conclusion, kañiwa may offer an alternative to traditional cereals as a health-promoting food ingredient. 相似文献
305.
Cristina Megías Justo Pedroche María del Mar Yust Manuel Alaiz Julio Girón-Calle Francisco Millán Javier Vioque 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(2):86-93
Plant protein hydrolysates are a source of bioactive peptides. There are peptides that decrease the micellar cholesterol solubility
from bile acids and therefore may reduce in vivo cholesterol absorption. The presence of these peptides in sunflower protein hydrolysates has been studied. Sunflower protein
hydrolysates produced with alcalase plus flavourzyme or with pepsin plus pancreatin inhibited in some degree the cholesterol
incorporation to micelles. Protein hydrolysates generated after 30 min of hydrolysis with alcalase, and after 30 min of hydrolysis
with pepsin, were the inhibitoriest of the cholesterol incorporation to micelles. The average amino acid hydrophobicity of
inhibitory peptides in cholesterol micelles was higher than the observed in the corresponding protein hydrolysates. This high
hydrophobicity probably favours their inclusion in the lipid micelles. In vivo, this inhibition may translate in a decrease of cholesterol absorption. Reported results show that a combination of different
characteristics such as peptide size or hydrophobicity may be responsible of the inhibitory activity of generated peptides. 相似文献
306.
Fanny Álvaro Julio Isidro Dolors Villegas Luis F. García del Moral Conxita Royo 《Field Crops Research》2008
Four field experiments comparing 24 durum wheat varieties grown at different periods during the 20th century in Italy and Spain were carried out to assess the changes caused by breeding activities on the number of grains per main spike and its determinants: number of spikelets per spike, number of grains per spikelet, fertile flowering and grain setting. Increases of 0.14 grains spike−1 year−1 (0.43% year−1 in relative terms) and 0.08 grains spike−1 year−1 (0.22% year−1) were observed in Italian and Spanish varieties, respectively. The overall change in the number of grains per spike in Italian germplasm (29.5%) was due to increases in both, the number of spikelets per spike (7.5%) and the number of grains per spikelet (20.3%), while in Spanish varieties the increase in the number of grains per spike (19.5%) was only attributed to the improvement of the number of grains per spikelet. The increase in the number of fertile florets per spike (about 12%) was similar in both countries, but while it explained more than 70% of the changes in the number of grains per spike in Spanish varieties, grain setting was responsible for most of the improvement in the number of grains per spike in the Italian germplasm. The percentage of florets setting grains was 68 and 64% in modern Italian and Spanish varieties, respectively. Most of the changes in the number of grains per spikelet were found in the upper part of the spike on Italian varieties, whilst they were more evenly distributed in the Spanish ones. The main achievement derived from the introduction of the Rht-B1 dwarfing gene was an increase in the number of grains per spikelet, but it did not have any effect on the number of spikelets on the main spike. The lack of genetic associations between grain setting and both the number of spikelets per spike and the number of fertile florets per spike suggests that future yield gains may be obtained through increases in the three components independently. 相似文献
307.
Rocío JaraboMª Concepción Monte Angeles BlancoCarlos Negro Julio Tijero 《Industrial Crops and Products》2012,36(1):14-21
Nowadays, certain components of non-wood annual plants such as corn stalk and industrial hemp core are considered waste materials or used in low value applications; both by-products have a very low cost. On the other hand, given the large quantities of these materials generated worldwide and their renewable character, it is reasonable to explore new routes for their exploitation. The aim of this paper is to study the potential of both corn stalk (Zea Mays L.) and industrial hemp core (Cannabis Sativa L.) fibres as a renewable source of cellulose fibres in the production of fibre-cement. For each source of fibres, a number of chemical cooking treatments were studied. The morphological properties of the fibres were determined using a scanning electron microscope and a fibre and pulp morphological analyser. Pulp refining was carried out in a PFI mill to improve the characteristics of the fibres. In the case of corn fibres, different degrees of refining were applied. The fibre flocculation process was investigated using several polyacrylamides. The process was studied by monitoring the chord size distribution in real time by means of a focused beam reflectance measurement probe.The results indicated that both pulps can be used for the production of fibre-cement, having the two types of pulp morphological similarities with the pine fibres currently used.Through the flocculation process it was concluded the floc size depends on the length of the fibres. 相似文献
308.
309.
Solange de Carvalho Maria José Tavarez Ranzani Paiva Jakeline Galvão de França Francisco Filipak Neto Ciro Alberto de Oliveira Ribeiro Julio Vicente Lombardi 《Aquaculture Research》2014,45(4):736-741
The objective of this study was to evaluate the effect of two concentrations of copper (0.13 and 0.5 mg L?1) on juveniles of tilapia, Oreocromis niloticus (Linnaeus), using two toxicological assays (I‐ copper exposure and II‐ copper exposure followed by recovery). Doses were taken from the liver of the test organisms to determine the concentrations of copper, reduced glutathione, activities of glutathione S‐transferase and catalase, and lipid peroxidation. Exposure to copper in both assays resulted in significant accumulation of this metal in the analysed tissue and in decreased concentration of reduced glutathione. There was no alteration in the activities of catalase and glutathione S‐transferase and in lipid peroxidation. 相似文献
310.
Pharmacokinetics of marbofloxacin after intravenous and intramuscular administration to ostriches 总被引:3,自引:0,他引:3
de Lucas JJ Rodríguez C Waxman S González F Uriarte I San Andrés MI 《Veterinary journal (London, England : 1997)》2005,170(3):364-368
The pharmacokinetics of marbofloxacin was investigated after intravenous (IV) and intramuscular (IM) administration, both at a dose rate of 5 mg/kg BW, in six clinically healthy domestic ostriches. Plasma concentrations of marbofloxacin was determined by a HPLC/UV method. The high volume of distribution (3.22+/-0.98 L/kg) suggests good tissue penetration. Marbofloxacin presented a high clearance value (2.19+/-0.27 L/kgh), explaining the low AUC values (2.32+/-0.30 microgh/mL and 2.25+/-0.70 microgh/mL, after IV and IM administration, respectively) and a short half life and mean residence time (t(1/2 beta)=1.47+/-0.31 h and 1.96+/-0.35 h; MRT=1.46+/-0.02 h and 2.11+/-0.30 h, IV and IM, respectively). The absorption of marbofloxacin after IM administration was rapid and complete (C(max)=1.13+/-0.29 microg/mL; T(max)=0.36+/-0.071 h; MAT=0.66+/-0.22 h and F (%)=95.03+/-16.89). 相似文献