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21.
María J. Estrela Jos A. Valiente David Corell David Fuentes Alejandro Valdecantos 《Agricultural and Forest Meteorology》2009,149(11):1896
A mountainous plot located in the interior of the Valencia region (east coast of the Iberian Peninsula) was identified for reforestation using the fog-water collection potential prevailing in the area. Fog data were obtained by means of an instrument ensemble consisting of a passive cylindrical fog-water collector, a rain gauge, a wind direction and velocity sensor and a temperature and humidity probe. Preliminary results gave rise to the additional deployment of a low-cost 18-m2 flat-panel collector connected to three 1000-l tanks for larger scale fog-water collection and storage. The 2007 annual rate of fog water that could be derived from the instrument ensemble amounted to 3.3 l/m2/day, which turn out to fill up the storage tanks completely in only 5 months, even though the flat-panel collector could not be operative 100% of the time. The study made use of the in situ stored water and a micro-irrigation network to irrigate a plot of reforestation seedlings through small water pulses localized deep in the planting hole during the summer dry period. Until the present, this forest location had always shown a difficult self-recovery due to the high level of land degradation resulting from recurrent forest fires in the past. Results indicate that survival rates and seedling performance of the two species planted, Pinus pinaster and Quercus ilex, improved with the use of small timely waterings and additional treatments with composted biosolid. 相似文献
22.
Masculinization of the Native Bay Snook,Petenia splendida,Using Oral Administration of the Synthetic Steroid 17α‐methyltestosterone 下载免费PDF全文
María de J. Contreras‐García Wilfrido M. Contreras‐Sánchez Alejandro Mcdonal‐Vera Ulises Hernández‐Vidal 《Journal of the World Aquaculture Society》2018,49(5):889-896
The possibility of inducing sex reversal in bay snook, Petenia splendida, was evaluated to generate a protocol aimed at producing single‐sex populations (100% males) and improving farming conditions for this species. This popular staple food is a cichlid fish native to Central America, with aquaculture potential. We evaluated oral administration of the synthetic steroid 17α‐methyltestosterone (MT) to determine optimal dosage (30, 45, and 60 mg/kg of food) and days of feeding (30, 45, and 60) to attain efficient masculinization. The statistical analysis indicates a highly significant effect of both factors as well as for the interaction (P < 0.01). We registered significant differences in growth at the end of the experiment; fish fed with 60 mg of MT for 60 d reached the largest size, while fish fed with no MT were smaller. No significant differences were observed for survival (P > 0.05), ranging from 55.7 to 75.3% in the treatments. We recommend the use of 60 mg/kg of MT for 30 d for achieving successful sex reversal. This study provides valuable information supporting the inclusion of new species in aquaculture, reducing time and costs associated with sex reversal previously proposed for the species. 相似文献
23.
Carrasco-Pancorbo A Cerretani L Bendini A Segura-Carretero A Del Carlo M Gallina-Toschi T Lercker G Compagnone D Fernández-Gutiérrez A 《Journal of agricultural and food chemistry》2005,53(23):8918-8925
Virgin olive oil has a high resistance to oxidative deterioration due to its tryacylglycerol composition low in polyunsaturated fatty acids and due to the presence of a group of phenolic antioxidants composed mainly of polyphenols and tocopherols. We isolated several phenolic compounds of extra virgin olive oil (phenyl-ethyl alcohols, lignans, and secoiridoids) by semipreparative high-performance liquid chromatography (HPLC) and identified them using ultraviolet, atmospheric pressure chemical ionization, and electrospray ionization MS detection. The purity of these extracts was confirmed by analytical HPLC using two different gradients. Finally, the antioxidant capacity of the isolated compounds was evaluated by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radical, by accelerated oxidation in a lipid model system (OSI, oxidative stability instrument), and by an electrochemical method. 相似文献
24.
Benavente-García O Castillo J Del Baño MJ Lorente J 《Journal of agricultural and food chemistry》2001,49(1):189-191
Significant technological advantages in terms of sweetness synergy and hence cost-saving can be obtained if neohesperidin dihydrochalcone (NHDC) is used in sweetener blends with other intense or bulk sweeteners. The combination of NHDC with sodium saccharin or sodium cyclamate is an excellent method to improve the water solubility at room temperature of NHDC. In the case of NHDC-sodium saccharin, two different methods for blend preparation, a simple mixture and a cosolubilized mixture, can be used, with similar results obtained for solubility and solution stability properties. To improve temporally the water solubility of NHDC in combination with sodium cyclamate, it is absolutely necessary to prepare cosolubilized blends. 相似文献
25.
Iglesias MT De Lorenzo C Del Carmen Polo M Martín-Alvarez PJ Pueyo E 《Journal of agricultural and food chemistry》2004,52(1):84-89
With the aim of finding methods that could constitute a solid alternative to melissopalynological and physicochemical analyses to determine the botanical origin (floral or honeydew) of honeys, the free amino acid content of 46 honey samples has been determined. The honeys were collected in a small geographic area of approximately 2000 km(2) in central Spain. Twenty-seven honey samples were classified as floral and 19 as honeydew according to their palynological and physicochemical analyses. The resulting data have been subjected to different multivariant analysis techniques. One hundred percent of honey samples have been correctly classified into either the floral or the honeydew groups, according to their content in glutamic acid and tryptophan. It is concluded that free amino acids are good indicators of the botanical origin of honeys, saving time compared with more tedious analyses. 相似文献
26.
Del Río JC Jiménez-Barbero J Chavez MI Politi M Gutiérrez A 《Journal of agricultural and food chemistry》2006,54(23):8744-8748
A series of phenylphenalenone type compounds, known to play a role as phytoalexins in plants of the Musaceae family, have been identified for the first time in the leaf fibers of abaca (Musa textilis). Among the phenylphenalenone type compounds identified, the structure of a novel compound, (1R)-2,3-dihydro-4,9-dihydroxy-8-methoxy-1-phenylphenalene, has also been described in abaca fibers. Its structure was elucidated by analysis of one- and two-dimensional NMR (correlation spectroscopy, heteronuclear single quantum correlation, and heteronuclear multiple bond correlation) spectroscopic data. 相似文献
27.
Eguaras M Del Hoyo M Palacio MA Ruffinengo S Bedascarrasbure EL 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2001,48(1):11-14
An organic product based on formic acid in a gel matrix was evaluated for use in Varroa control under autumnal climatic conditions in Argentina. Twenty colonies each received two gel packets with formic acid in two applications and numbers of falling mites were registered. After this treatment colonies received two other acaricides in order to compare efficacy. Average final efficacy in colonies treated with the organic product was 92% with a low variability. The gel matrix kept an adequate formic acid concentration inside the colonies with only two applications. This product is, therefore, a good alternative for Varroa control because it is organic, easy to use and presents a low variability in final efficacy between colonies. No queen, brood, or adult honeybee mortality was registered. 相似文献
28.
Pioli RN Morandi EN Martínez MC Lucca F Tozzini A Bisaro V Hopp HE 《Phytopathology》2003,93(2):136-146
ABSTRACT Isolates of the Diaporthe/Phomopsis (D/P) complex were collected in the main soybean producing area of Argentina during the 1996-97, 1997-98, and 1998-99 growing seasons. Twenty-three morphologic characters related to type of colonies, stroma, pycnidia and conidia, presence of perithecia, and asci length were studied by principal component analysis (PCA). Genomic DNA were analyzed by the random amplified polymorphic DNA (RAPD) technique. From both studies, 18 isolates were identified as D/P complex and grouped in four major taxa: (i) Diaporthe phaseolorum var. meridionalis, (ii) D. phaseolorum var. caulivora, (iii) D. phaseolorum var. sojae, and (iv) Phomopsis longicolla. In addition to distinguishing interspecific and intraspecific variability, molecular markers allowed the detection of differences among isolates within the same variety. Pathogenicity was assayed in the greenhouse, by the toothpick method, inoculating the D/P isolates to soybean genotypes carrying different resistance genes (Rdc1, Rdc2, Rdc3, and Rdc4) against soybean stem canker (SSC). Pathogenic analysis distinguished two main groups: (i) the SSC-producing isolates, including D. phaseolorum var. meridionalis and D. phaseolorum var. caulivora, and (ii) the non-SSC-producing isolates, including D. phaseolorum var. sojae and P. longicolla. Cultivar RA-702 (susceptible control) was compatible with both D. phaseolorum var. meridionalis and D. phaseolorum var. caulivora isolates; meanwhile, Tracy-M (Rdc1 and Rdc 2 genes) was incompatible with D. phaseolorum var. meridionalis but compatible with D. phaseolorum var. caulivora isolates. The fact that Rdc1 and Rdc2 together (as in Tracy-M) confer an almost immune reaction to all assayed isolates of D. phaseolorum var. meridionalis but were ineffective against the D. phaseolorum var. caulivora isolates evaluated suggests that the virulence or avirulence genes in D. phaseolorum var. meridionalis and D. phaseolorum var. caulivora are different. Moreover, physiological races of D. phaseolorum var. meridionalis were detected by using differential soybean genotypes carrying distinct single Rdc genes. As far as we know, this is the first report on the existence of physiological races of D. phaseolorum var. meridionalis in South America. Selective pressure due to deployment of resistant host cultivars may have changed the frequency of the virulence or avirulence genes within the population of D. phaseolorum var. meridionalis. On the whole, our results show that pathogenic variability of D. phaseolorum in the core soybean-producing area of Argentina is higher than previously recognized. 相似文献
29.
30.
Rossi R Dörig S Del Prete E Scharrer E 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2000,47(1):9-16
The effect of intraperitoneal injection of D,L- or D-beta-hydroxybutyrate on feed intake and plasma metabolites was investigated in pygmy goats. The combined intraperitoneal injection of D,L-beta-hydroxybutyrate or D-beta-hydroxybutyrate (15 mmol/kg0.75) and 1,3-butanediol (6.6 mmol/kg0.75), a ketogenic substrate, decreased cumulative food intake while the same dose of 1,3-butanediol or DL-beta-hydroxybutyrate alone had no effect. The decrease in food intake after combined injection of D-beta-hydroxybutyrate and 1,3-butanediol was characterized by a significant decrease in meal frequency and a prolongation of the latency to eat. The hypophagic effect of the combined injection of D-beta-hydroxybutyrate and 1,3-butanediol was significant for 8 h, while the hypophagia after D,L-beta-hydroxybutyrate and 1,3-butanediol was significant for only 2 h after injection. Injection of D,L-beta-hydroxybutyrate increased plasma D-beta-hydroxybutyrate levels to 0.55 mmol/l and decreased plasma free fatty acids. Addition of 1,3-butanediol (6.6 mmol/kg0.75) to the injection increased plasma D-beta-hydroxybutyrate level up to 0.75 mmol/l. The results show that parenteral administration of D-hydroxybutyrate reduces feed intake in pygmy goats and that the hypophagia appears to be related to the amount of D-beta-hydroxybutyrate injected. The hypophagia seems to be related to elevated plasma D-beta-hydroxybutyrate concentration, and the threshold concentration appeared to be about 0.7 mmol/l under the experimental conditions of this study. 相似文献